HK1240063A1 - Endoluminal device and method - Google Patents

Description

Endoluminal device and method

The application is a divisional application of Chinese patent applications with application date of 24.1.2013, application number of 201380014790.2 and invention name of intracavity device and method, and the original application is a Chinese national stage application of international application PCT/US 2013/023030.

Cross Reference to Related Applications

This application is a continuation-in-part application of U.S. application No.13/179,458 filed on 8/7/2011, which is a continuation-in-part application of U.S. application No.13/153,257 filed on 3/6/2011, which is a continuation-in-part application of U.S. application No.13/118,388 filed on 28/5/2011, which is a continuation-in-part application of U.S. application No.12/790,819 filed on 29/5/2010, which is a continuation-in-part application of U.S. application No.12/483,193 filed on 11/6/2009, which is a continuation-in-part application of U.S. application No.11/955,331 (now U.S. patent No.7,896,911) filed on 12/2007. U.S. application No.13/179,458 claims priority to U.S. provisional application No.61/362,650 filed on 8/7/2010. U.S. application No.13/118,388 claims priority to U.S. provisional application No.61/349,836 filed on 29/5/2010. This application claims priority to U.S. provisional application No.61/590,775 filed on 25/1/2012. All of the above applications are incorporated by reference into this application and made a part of the specification.

Technical Field

The present invention relates to the treatment of atherosclerotic occlusive disease by an endovascular procedure that pushes and holds plaque that accumulates on the walls of blood vessels away from the way blood flow is resumed.

Background

Atherosclerotic occlusive disease is a leading cause of stroke, myocardial infarction, limb defects, and death in the united states and the industrialized world. Atherosclerotic plaques form a hard layer along the arterial wall and are composed of calcium, cholesterol, compacted thrombus, and cellular debris. As atherosclerosis progresses, the blood supply intended to pass through a particular blood vessel is reduced or even prevented by the occlusion process. One of the most widely used methods for treating clinically significant atherosclerotic plaques is balloon angioplasty.

Balloon angioplasty is an accepted method of opening a closed or stenotic vessel in each vascular bed of the body. Balloon angioplasty is performed using a balloon angioplasty catheter. Balloon angioplasty catheters include a cigar-shaped, cylindrical balloon attached to a catheter. A balloon angioplasty catheter is placed in an artery from a remote access site created either percutaneously or by open exposure of the artery. The catheter is passed along the interior of the vessel over a wire that guides the catheter path. The balloon-attached catheter portion is placed at the site of the atherosclerotic plaque in need of treatment. The balloon is inflated to a size consistent with the original diameter of the artery prior to the occurrence of occlusive disease. When the balloon is inflated, the plaque is destroyed. The cleavage planes are formed within the plaque, allowing the plaque to expand in diameter using an expansion balloon. Often, plaque fragments are more resistant to expansion than the rest of the plaque. When this occurs, pumping more pressure into the balloon results in full inflation of the balloon to reach the predetermined size. The balloon is deflated and removed, and the arterial segment is re-examined. The treatment of balloon angioplasty is an uncontrolled plaque rupture treatment. The lumen of the blood vessel at the treatment site is usually slightly larger, but not always larger and unreliable.

Some of the cleavage planes produced by plaque rupture using balloon angioplasty may form denuded bodies (discontinuities). Exfoliation occurs when a portion of plaque is lifted off an artery, does not adhere completely to the artery, and can be mobile or loose. Plaque that has been destroyed by spalling protrudes into the flow stream. If the plaque is raised completely in the direction of blood flow, it may obstruct flow or cause acute occlusion of the vessel. There is evidence that the denuded body after balloon angioplasty must be treated to prevent occlusion and to resolve residual stenosis. There is also evidence that in some cases it may be better to place a metal holding structure, such as a stent, to hold the artery open after angioplasty and to force the exfoliated material against the vessel wall to create a suitable lumen for blood flow.

Currently, clinical management of denuded bodies after balloon angioplasty is mainly performed using stents. As shown in fig. 1, the stent 3 is a tube with a diameter sized to fit the artery 7. The stent is placed in the artery at the site of exfoliation to force the exfoliation of a flap (flap) against the inner wall of the vessel. Stents are typically made of metal alloys. Stents have varying degrees of flexibility, visibility, and placement techniques. A stent is placed in each vascular bed of the body. The development of stents has significantly altered the approach to minimally invasive treatment of vascular disease, making it safer and in many cases more durable. The use of stents significantly reduces the incidence of acute occlusion following balloon angioplasty.

However, stents have significant disadvantages and many studies and developments have been made to solve these problems. Stents induce repeated stenosis (recurrent stenosis) of the treated vessel. Recurrent stenosis is a "fatal weakness" of a stent. Depending on the location and size of the artery, ingrowth of intimal hyperplasia tissue from the vessel wall between struts (strut) or through openings in the stent may occur and cause failure of the revascularization by narrowing or closure of the stent. This may occur at any time after placement of the stent. In many cases, even in stent segments placed over arterial segments that are not particularly narrowed or diseased during the initial stenting procedure, the stent itself appears to stimulate a local vessel wall reaction that causes a stenosis. This response of the vessel to the presence of the stent may be due to the scaffolding (scaffold) action of the stent. The response of the recurrent stenosis or the tissue growing in the vessel is in response to the stent. This behavior suggests that the widely used metal in arteries and vessel coverage just as a stent causes stenosis. Recurrent stenosis is a problem because it causes stent failure and there is no effective treatment. Existing treatments for this problem include; repeat angioplasty, cutting balloon angioplasty, cryoplasty, atherectomy (atherectomy), or repeat stenting. None of these methods has had a high degree of long-term success.

The stent may also break due to material stress. Stent fractures may occur due to long-term material stresses and are associated with the occurrence of recurrent stenosis at the material fracture. This is a relatively new finding and it may require a specific stent design for each application in each vascular bed. The structural integrity of the stent remains a current problem for its use. Arteries, particularly mobile (e.g., lower extremity arteries and carotid arteries) are of particular interest. The integrity of the entire stent is tested at any time when the vessel is bent or compressed anywhere along the stent segment. One reason why stent rupture occurs is because the already treated arterial segment is longer than the arterial segment that needs to be treated. The skeletal action of the stent affects the mechanical behavior of the entire artery, causing the artery to become less flexible. Available stent materials have limited bending cycles and are prone to failure at high frequency repetitive bending sites.

Many arterial segments are implanted with stents even when they do not require stents, thereby exacerbating the drawbacks of stents. There are several reasons for this. In many cases more than one stent needs to be placed and often several stents are required. Most of the stent length is usually placed on a segment of the artery that does not require stent implantation and only borders the area of exfoliation or disease. Stents that are adjusted to the exact length of the lesion are not available. When one tries to place multiple stents and place multiple stents in the segment where the stent most needs to be implanted, the cost is very expensive because each stent requires installation and material. The time taken to do so also increases the cost and risk of operation. The longer the artery receives an unnecessary stent, the stiffer the artery and the greater the skeletal effect that occurs. This may also help stimulate the arterial response to the stent causing the recurrent stenosis.

Disclosure of Invention

There is a continuing need to develop new and improved devices to assist in the treatment of vascular disease, including atherosclerotic occlusive disease, and for example for the purposes described above.

In some embodiments, the self-expanding endoluminal device can be configured for precise positioning during deployment within a vessel. The endoluminal device has a longitudinal axis extending between a distal end and a proximal end, the endoluminal device configured for radial compression and expansion. The endoluminal device can include a first undulating ring disposed at a distal end and a proximal portion. The first undulating ring may extend circumferentially about the longitudinal axis, the first undulating ring comprising a plurality of struts, a plurality of inner apices, and a plurality of outer apices, wherein at least two struts are connected at one of the apices, the outer apices being distal to the inner apices. The proximal portion may be connected to the inner vertex. The endoluminal device is configured for delivery such that the first undulating ring may be at least partially expanded while the proximal portion remains compressed. In this position, a first strut of the plurality of struts extends at a radially outward angle from the longitudinal axis, the first strut connected to the compressed proximal end; and a second strut and a third strut of the plurality of struts are connected to the first strut and extend parallel to the longitudinal axis, the second strut and the third strut forming legs and the endoluminal device comprising a plurality of such legs, the legs configured to extend parallel to the longitudinal axis when the endoluminal device is in such partially expanded position, the legs positioned circumferentially about the longitudinal axis and configured to precisely position and orient the endoluminal device within the vessel as the endoluminal device is further expanded and deployed within the vessel.

The endoluminal device may be a tack (tack), stent, vascular implant, or other type of implant.

According to some embodiments, the endoluminal device may include a first circumferential member disposed at a distal end of the endoluminal device, the first circumferential member having a first outer apex disposed between the first strut and the second strut, a second outer apex disposed between the third strut and the fourth strut, a first inner apex disposed between the second strut and the third strut, and a second inner apex disposed adjacent to the fourth strut; a second circumferential member disposed at a proximal end of the endoluminal device; and a bridge member having a first end coupled to the second internal apex and a second end coupled to the second circumferential member, the bridge member having a plaque anchor disposed at or adjacent a central region of the bridge member. The first inner apex may extend a first axial distance from the central region of the bridge member and the second inner apex may extend a second axial distance from the central region of the bridge member, the first distance being greater than the second distance such that the second strut and the third strut form a leg, the leg may extend outwardly from the second circumferential member when the endoluminal device is in a partially expanded position, the leg being substantially parallel to a longitudinal axis of the endoluminal device.

In some embodiments, the endoluminal device can include a first circumferential member disposed at a distal end of the endoluminal device, the first circumferential member can have a first outer apex disposed between the first strut and the second strut, a second outer apex disposed between the third strut and the fourth strut, a first inner apex disposed between the second strut and the third strut, and a second inner apex disposed adjacent to the fourth strut; and a second circumferential member disposed at the proximal end of the endoluminal device. The first internal apex is positioned away from the second internal apex such that the second strut and the third strut form a leg that can extend outwardly from the second circumferential member when the endoluminal device is in a partially expanded position, the leg being substantially parallel to a longitudinal axis of the endoluminal device.

An endoluminal device may include a first circumferential member and a second circumferential member disposed at both ends of the endoluminal device. The first circumferential build may have an undulating configuration with a plurality of inner and outer apices and struts extending therebetween. A method of placing an endoluminal device can include withdrawing an outer sheath such that a portion of the endoluminal device expands earlier than the rest of the endoluminal device.

An endoluminal device can include a proximal circumferential member and a distal circumferential member. A proximal circumferential member may be disposed at the proximal end of the endoluminal device. A distal circumferential member may be disposed at a distal end of the endoluminal device. In some embodiments, the distal circumferential member is a distal-most aspect of the endoluminal device and the proximal circumferential member is a proximal-most aspect of the endoluminal device. The proximal and distal circumferential members are connected by a bridge member. The bridging member may comprise one or more anchors configured to engage the plaque and/or the vessel wall.

In some embodiments, a catheter-based endoluminal device can include a proximal circumferential member, a distal circumferential member, and a plurality of bridging members. The proximal circumferential member may be disposed at a proximal end of the endoluminal device and have a sinusoidal configuration with a plurality of first inner apices, a plurality of first outer apices, a plurality of second inner apices, and a plurality of second outer apices, each of the plurality of second inner apices being proximally spaced from the plurality of first inner apices. The distal circumferential member may be disposed at the distal end of the endoluminal device and have a sinusoidal configuration with a plurality of third inner apices, a plurality of third outer apices, a plurality of fourth inner apices, and a plurality of fourth outer apices, each of the plurality of fourth inner apices being distally spaced from the plurality of third inner apices. Each bridging member may connect one of the plurality of first internal vertices of the proximal circumferential member to one of the plurality of third internal vertices of the distal circumferential member. Each apex of the plurality of fourth apices of the distal circumferential member may not be connected to any bridge member of the plurality of bridge members or any second apex of the plurality of second apices of the proximal circumferential member.

In some embodiments, the endoluminal device can include a first circumferential member disposed at the proximal or distal end of the endoluminal device, a second circumferential member disposed adjacent to the first circumferential member, and a bridge member. The first circumferential member may have a first outer apex disposed between the first strut and the second strut, a second outer apex disposed between the third strut and the fourth strut, a first inner apex disposed between the second strut and the third strut, and a second inner apex disposed adjacent to the fourth strut. The bridge member may have a first end coupled with the second internal apex and a second end coupled with the second circumferential member. The bridge member may also have plaque anchors disposed at or adjacent to a central region of the bridge member. The first inner vertex may extend a first axial distance from the central region of the bridge member and the second inner vertex may extend a second axial distance from the central region of the bridge member, the first distance being greater than the second distance.

In some embodiments, a method of placing an endoluminal device can include one or more of the following steps. A catheter system is provided that includes an elongate body having a delivery platform disposed adjacent a distal end of the elongate body and a marker band at a distal end of the delivery platform, the delivery platform having an endoluminal device disposed thereon and an outer sheath over the endoluminal device. The distal end of the elongate body is advanced through the patient's vasculature until the marker band is located at the treatment area. The marker bands are visualized to confirm the position of the delivery platform relative to the treatment area. The outer sheath is retracted while maintaining the position of the elongate body such that the plurality of legs of the first circumferential member disposed at the distal end of the endoluminal device are released from the delivery platform prior to release of the remainder of the endoluminal device. The first circumferential member may include: a first outer apex disposed between the first leg and the second leg, a second outer apex disposed between the third leg and the fourth leg, a first inner apex disposed between the second leg and the third leg, and a second inner apex disposed adjacent to the fourth leg. The legs may include a first inner apex, a first outer apex, a second strut, and a third strut, the legs assuming a pre-fully deployed position prior to full expansion.

Drawings

These and other features, aspects, and advantages are described below with reference to the drawings, which are for purposes of illustration only and are not limiting of the invention. In the drawings, like reference numerals designate corresponding parts throughout the similar embodiments.

FIG. 1 illustrates the use of a stent installed after angioplasty as is conventional practice in the prior art.

Figure 2 shows the use of installed plaque pegs after endoluminal surgery, demonstrating an advantage over the prior art.

Figure 3A illustrates an end view of an embodiment of a plaque tack, figure 3B illustrates a side view of an embodiment of a plaque tack, figure 3C illustrates a perspective view of the plaque tack, and figure 3D illustrates a plan or deployed view of a portion of the plaque tack.

Fig. 4 is a schematic view of the distal portion of the delivery device expanded in a blood vessel having been advanced to a treatment site.

Fig. 4A shows the proximal end of one embodiment of a delivery device.

Fig. 4B is a plan view of the distal end of the delivery device shown in fig. 4.

FIG. 4C is a cross-sectional view of the distal end portion of FIG. 4B showing a plurality of tack devices ready for implantation.

FIG. 4D illustrates deployment of two tack devices after sheath retraction.

Figures 5A and 5B illustrate another embodiment of a plaque tack in a collapsed state and an expanded state, respectively.

Figure 5C shows a detailed view of a portion of the plaque tack of figures 5A-5B.

Fig. 5C1 shows a variation of the embodiment of fig. 5A-5C with anchors of increased size.

Fig. 5D shows a variation of the embodiment of fig. 5A-5C with an anchor disposed on the midline of the staple.

Fig. 5E shows the struts tapering from a wider portion at the lateral edges of the nail to a narrower portion at the middle portion of the struts and/or widening from a narrow portion at the middle portion of the struts to a central location of the nail.

FIG. 5F shows a variation of a staple having internal vertices spaced from other internal vertices.

Fig. 5G shows the staple partially expanded during delivery.

Fig. 5H to 5J show further variants of the nail.

Figure 6A is a graph comparing the expansion force of plaque spikes to stents.

Figure 6B illustrates the use of multiple plaque pegs spaced in length at their treatment sites compared to a typical stent.

Figure 7A illustrates another embodiment of a plaque tack in a fully compressed state. Figure 7D shows the plaque tack in a fully expanded state, and figures 7B and 7C show the plaque tack in an expanded state between a fully compressed and fully expanded state.

Fig. 8 is a schematic view of a focal elevating element (focal elevating element) of the plaque tack shown in fig. 7A-7D.

Fig. 9 is a schematic diagram showing variables used to calculate the nail surface lift due to the use of a focal lifting element in the plaque tack device.

Figure 10 illustrates the use of a plaque tack with focal elevating elements for holding plaque against the vessel wall.

Fig. 11 and 12 show a variant of the use of a focal elevating element on a plaque tack.

Figures 13 and 14 show another variation of a focal elevating element on a plaque tack.

Fig. 15 illustrates the use of a focal elevating element to reshape the artery wall to a desired cross-sectional shape.

Figures 16-22 illustrate variations of forming and positioning a focal elevating element on the post of the plaque tack.

Figures 23-29 illustrate a method of delivering a plaque tack into a blood vessel.

Fig. 30A-30B illustrate focal elevating elements engaging plaque.

Fig. 31A-31B show anchors engaging plaque.

Fig. 32A-32B show proximal and distal views, respectively, of a system for delivering a vascular prosthesis, wherein the distal end of the sheath of the system is disposed distal of one or more plaque pegs.

Fig. 33A-33B illustrate proximal and distal end views, respectively, of the system of fig. 32A-32B, with the sheath distal end disposed proximal of one or more plaque pegs.

Fig. 34 shows a system for delivering a vascular prosthesis.

FIG. 35 shows a sheath that can be used to retain and deploy one or more staples.

Figures 36-36A illustrate one embodiment of an elongate body that can have one or more plaque pegs disposed therearound within the sheath shown in figure 35.

Fig. 36B-36F illustrate embodiments of markers on a delivery system.

Fig. 37A-37B illustrate a variation of the delivery system in which an active actuation member is provided to anchor the system near the treatment region.

Fig. 38 shows a variation of the delivery system in which a linkage is provided to position the active actuation member near the treatment area.

Fig. 39-40 illustrate a delivery system having a passive dilation member for stabilizing the distal delivery region.

Figure 41 shows a delivery system with an abrasive isolation sheath to stabilize the distal delivery zone.

Fig. 42 illustrates a delivery system incorporating a deployable bag for maintaining spacing between adjacent prostheses.

FIG. 43 illustrates one embodiment of a deployment bag adapted to maintain spacing between adjacent prostheses.

Fig. 44 shows a delivery system including a deployable bag for maintaining spacing between adjacent prostheses, with a constraining element disposed within the peg.

Figure 45 shows a balloon optimized for deploying a plaque tack to induce plaque anchors to rotationally engage plaque.

Fig. 45A shows a balloon used to deploy a plurality of staples.

Fig. 46-48D illustrate a portion of a deployment system that may be used with any of the delivery systems disclosed herein.

FIG. 49 illustrates a shuttle deployment device.

Detailed Description

The subject matter of the present application relates to improvements in plaque tack or staple devices. The plaque tack or staple device may be used to treat atherosclerotic occlusive disease. Plaque pegs may be used to hold loose plaque against the vessel wall. The plaque tack may comprise an annular member configured to apply a distraction force to the loose plaque.

I. Overview of intraluminal nail treatment

Figure 2 illustrates one embodiment of a plaque tack or staple device 5 comprising a thin, annular band or ring of durable, flexible material. The tack device may be inserted into a blood vessel in a compressed state and installed in an expanded state against the vessel wall at one or more specific locations of loose plaque using a catheter delivery mechanism. The plaque tack 5 can be deployed after or as part of an angioplasty procedure. The plaque tack 5 is adapted to apply a spreading force against plaque in the blood vessel 7 to press and hold the plaque against the vessel wall. The stapling device may expand radially outward under a spring or other expansion force. Preferably, the fully expanded diameter of the staples 5 is larger than the transverse size of the vessel to be treated. As described below, the staples 5 can advantageously be deployed in a surprisingly wide range of vessel sizes.

The plaque tack 5 may contain a plurality of plaque anchors 9 on its outer annular periphery. By expanding up against the plaque, the plaque anchor 9 can be embedded into or placed in at least physical contact with the plaque by expansion against the plaque. In certain embodiments, the plaque anchor 9 is adapted to lift adjacent portions of the tack 5 relative to the vessel wall. In at least this sense, the anchoring member 9 may have some of the advantages of a focal elevating element as will be discussed in section III below. The anchoring elements 9 exert a retaining force on the plaque while minimizing the amount of material surface area that is in contact with the plaque or vessel wall. As another feature, the plaque tack 5 may extend over only a small area of the axial direction of the vessel wall to minimize the amount of foreign structure placed in the vessel. For example, each plaque tack 5 can have an axial length L that is only a small fraction of the axial length of a typical stent.

As shown in fig. 2, the plaque tack device of the present application is designed in a minimally invasive manner to tack loose or exfoliated atherosclerotic plaque to the artery wall. Plaque tacks can be used to treat atherosclerotic lesions ab initio or to treat the undesirable consequences of balloon angioplasty. The plaque tack is designed to maintain adequate lumen in the artery being treated without the inherent drawbacks of vascular stents. The device may also be used to administer drugs, fluids, or other therapeutic ("eluting") agents into the atherosclerotic plaque or blood vessel wall or into the bloodstream.

One or more plaque pegs 5 can be deployed precisely in locations along the length of the plaque accumulation site where a specific retention force is required to stabilize the site and/or to keep the plaque pieces out of the path of the blood stream.

Figure 2 shows that in various plaque tack treatments, multiple plaque tacks 5 can be deployed to treat axially spaced locations along the vessel 7. In this way, targeted therapy can be provided to hold loose plaque against the vessel wall without overtaking the stent as described below. The plaque tack 5 and installation process can be designed to share the various ways of a common method that utilizes the outward force of a spring-like annular band so that the tack can be compressed, folded, or twisted to occupy a small diameter volume so that it can be moved over a sheath or catheter to a position in a vessel and then released, opened, or untwisted (unspliced) within the vessel to an expanded state.

The plaque tack device can be delivered into the blood vessel from an intravascular insertion. Section IV below discusses a number of delivery methods and devices that may be used to deploy the plaque tack. The delivery devices used in the different embodiments may be the same or different (having features specifically designed to deliver a particular staple). The plaque tack and installation process can be designed to share the multiple ways of a common method that utilizes the expansion force of a delivery mechanism (e.g., balloon expansion) and/or the expansion force of a compressible annular band to enable the tack to be moved into position within a vessel and then released, opened, or untwisted within the vessel to an expanded state.

Other embodiments of the intraluminal staple

In these designs, for example in an open and closed cell structure (cell construction), variations of the plaque tack 5 may have a mesh configuration and may be configured with one or more circumferential members formed from separate struts.

A. Plaque nail with metal net structure

An embodiment of the plaque tack 10 in the form of a metal mesh structure is shown in figures 3A-3D. The illustrated plaque tack 10 has a closed cell structure with circumferential bands 10a formed from a staggered mesh, and radially outwardly extending projections 10 b. The plaque tack 10 can be formed by laser cutting or etching a metal tube or from thin metal wires looped and interlaced in a mesh, i.e., welded, brazed, looped and/or joined together to form the desired mesh shape as shown in figures 3C-3D. The projection 10b may project from the endless belt 10 a. The projections 10b may be on the outer surface of the staple and may be in contact with and/or embedded into the vessel wall.

The annular band of the plaque tack 10 can have a dimension (sometimes referred to herein as a length) in an axial direction along the vessel wall that is about equal to or less than its expanded diameter to minimize placement of foreign scaffolding in the vessel. The expanded diameter means the final diameter of the unconstrained expansion. One or more staples may be applied only at locations along the length of the plaque accumulation site where a specific retention force is required to stabilize the site and/or to keep the plaque pieces out of the path of the blood stream.

The mesh pattern may be designed such that the plaque tack 10 may compress radially inward to a smaller volume size. This may allow the plaque tack 10 to be loaded onto or into a catheter delivery device to be inserted into a blood vessel. For example, the staple 10 may have a generally circular shape with a bend (e.g., an internal V-bend) that allows the staple 10 to be zigzag folded into a compressed, smaller volume form for loading into a delivery catheter (e.g., a deployment tube).

At the desired location in the vessel, the compressed plaque tack 10 is released from the delivery catheter. The mesh in combination with the annular, ring-like shape may allow the plaque tack 10 to spring back to its expanded shape. Alternatively, the tack 10 may be expanded by another means, such as by a balloon. Figure 3C shows the plaque tack 10 at rest in its fully expanded state, and figure 3D shows a detail of a portion of the metal mesh.

Figures 4-4D illustrate that one or more plaque pegs 10 may be positioned at a treatment site in a patient's vasculature by a delivery device 11 having an outer sheath 13 and then expanded. The enhancement of the delivery device 11 is discussed in section IV below. The staples 10 may be expanded in any suitable manner, such as by being configured to self-expand or balloon expand. In the illustrated embodiment, a plurality of self-expanding staples 10 (or variants, such as staples 10' or staples 10 ") are disposed within a sheath 13. Delivery device 11 comprises an elongate body 11A disposed at least partially within a sheath 13. The delivery device 11 also includes an expandable structure 11B that can atraumatically move tissue and help guide the delivery device 11 through the vasculature. The body 11A may be configured with a lumen 11C extending therethrough for receiving and slidably advancing the guidewire 40 therein. In the embodiment shown, the sheath 13 and the expandable structure 11B meet to provide the delivery device 11 with a smooth outer surface, e.g., the same outer diameter, where the sheath and the expandable structure meet. The body 11A may be configured with a plurality of annular recesses 11D in which the spikes 10, 10', 10 "may be disposed. Annular recess 11D may be defined between one or more shoulders 11E that prevent the staple from sliding along the proximal or distal ends of elongate body 11A. The recess 11D may be removed by providing another structure for mounting the nail 10, 10', 10 "axially along the elongated body 10A.

Fig. 4A and 4D illustrate the proximal end of the device 11 and the manner in which the staples 10, 10', 10 "are deployed. In particular, the proximal end of the device 11 includes a handle 11F and an actuator 11G. The actuator 11G is coupled to the proximal end of the sheath 13 such that proximal and distal movement of the actuator 11G causes proximal and distal movement of the sheath 13. Fig. 4A shows the distal positioning of actuator 11G, which corresponds to the forward position of sheath 13 relative to elongate body 11A and recess 11D. In this position, the recess 11D and the nail 10, 10', 10 "are covered by the sheath. Proximal movement of the actuator 11G relative to the handle 11F causes the sheath 13 to move proximally to the position of fig. 4D, for example. In this position, the two distal-most ones of the staples 10, 10', 10 "are uncovered and allowed to self-expand in the manner described herein.

Returning now to fig. 3A-3B, the projections 10B on the surface of the tack 10 may act as anchors or lifting elements to embed into or press against plaque. An array of lifting elements or anchoring elements may be used to connect the circumferential band of staples with plaque (plaque) or vessel walls. The projection 10b may be made of a material that is sufficiently rigid to assume a locking or engaging relationship with the vascular tissue and/or pierce or engage the plaque and maintain a locking or engaging relationship therewith. The projection 10b may project at an angle of 90 degrees to the tangent of the endless belt, or an acute angle may be used.

The plaque tack may be made of materials such as corrosion resistant metals, polymers, composites, or other durable flexible materials. Preferred materials are metals with "shape memory" (e.g., Nitinol). In some embodiments, the staples may have an axial length of about 0.1mm to 6mm, an expanded diameter of about 1mm to 10mm, and an anchor height of from 0.01mm to 5 mm. Generally, the annular band of the plaque tack has a length in the axial direction of the vessel wall that is about equal to or less than its diameter to minimize the amount of foreign body structure that is disposed in the vessel. The ratio of the axial length to the diameter of the annular band can be as low as 1/100.

B. Plaque tack with open cell structure

Figures 5A-5C illustrate that in certain embodiments, the plaque tack 10' can be configured to have an open cell structure. The plaque tack 10' can comprise one or more circumferential members having an undulating (e.g., sinusoidal) configuration and spaced from each other in an axial direction. The circumferential members may be coupled together at one or more circumferentially spaced apart locations by axially extending members (sometimes referred to herein as bridge members). As described below, these embodiments are expandable over a wide range of diameters and may be deployed in a variety of different vessels.

The plaque tack 10' can have features similar to those described above with respect to the plaque tack 10. For example, the plaque tack 10' may also be laser cut or etched metal tube formed. Similarly, the plaque tack 10' may be made of materials such as corrosion resistant metals (e.g., certain coated or uncoated stainless steels or cobalt chrome alloys), polymers, composites, or other durable flexible materials. The preferred material is a metal with "shape memory" (e.g., nitinol).

Fig. 5A to 5B show the overall structure of the plaque tack 10' having an open cell configuration. Plaque tack 10' is shown having two circumferential members 12, which circumferential members 12 may be rings formed from a plurality of zig-zag struts, joined by bridges 14 extending between the rings 12. The rings and bridges define a column of bounded cells 16 along the outer surface of the nail. The outer surface extends around the outer circumference (e.g., at the outer circumference of the nail 10'). The boundary of each cell 16 is made up of a plurality of members or struts. As shown, the second ring is a mirror image of the first ring, although the first and second rings may be circumferential members having different configurations. Additionally, bridge 14 may be symmetrical across a transverse plane extending through its axial midpoint, but other configurations are possible. The rings 12 may be considered coaxial, where the term is broadly defined to encompass two spaced rings or structures having centers of rotation or mass disposed along a common axis (e.g., the central longitudinal axis of the nail 10').

Fig. 5C is a schematic plan view of a portion of the staple 10' showing a portion of the cell 16 and a portion of its boundary. The portion shown to the right of the midline C is one half of the cell 16 in one embodiment. The other half may be a mirror image, an inverted mirror image as shown in fig. 5A-B, or some other configuration. A portion of the ring 12 that is part of an individual cell 16 may define a portion of the pattern that repeats along the ring. In some embodiments, the loops 12 may have portions of a repeating pattern that extend across the cells, e.g., across 1.5 cells, 2 cells, 3 cells, etc. The pattern of the ring 12, in combination with the other features of the nail 10', enables it to be circumferentially compressible. The difference between the compressed state and the expanded state can be seen by comparing the compressed view shown in fig. 5A with the expanded view shown in fig. 5B.

The cells 16 of the nail 10' may be bounded by portions of the two rings 12 which are mirror images of each other. Accordingly, some embodiments may be fully described with reference to only one side of the staple 10' and unit 16. The ring 12 has an undulating sinusoidal pattern, a portion of which is shown in FIG. 5C. The undulating pattern may have one or more amplitudes, such as the illustrated double amplitude configuration.

The ring 12 may have a plurality of struts or structural members 26, 27, 28, 29. A plurality of struts may be repeated around the circumference of the ring 12. The struts may be of many different shapes and sizes. The struts may extend in a variety of different configurations. In some embodiments, a plurality of struts 26, 27, 28, 29 extend between the inner vertices 18, 19 and the outer vertices 24, 25.

In some embodiments, the outer apices 24, 25 extend axially at different distances measured from the centerline C or central region of the nail 10'. In particular, in this regard, vertex 24 may be considered a high vertex and vertex 25 may be considered a low vertex. The inner apices 18, 19 may be axially aligned, e.g., located at the same axial distance from the centerline C. Thus, the outer apex 24 is disposed further away from the bridge and the inner apex than the outer apex 25. In some embodiments, the axial length of the nail 10' is measured from the top of the outer apex 24 on one side of the unit 16 to the corresponding top of the outer apex 24 on the other side of the unit. In other words, the first external apex 24 extends a first axial distance from the midline C of the nail 10 'and the second external apex 25 extends a second axial distance from the central region C of the nail 10', the first distance being greater than the second distance. The cell 16 is shown with one high external apex 24 and one low external apex 25 on each side.

The bridge 14 may be connected to one or more internal vertices 18, 19. A bridge 14 may connect the two rings 12 together. Bridge 14 can have many different shapes and configurations. Some embodiments of the staple 10' have a proximal ring and a distal ring, and a bridge disposed between and connecting the proximal and distal rings. As noted above, bridge 14 may be located at a central region or midline C of staple 10'. In fig. 5C, the word "proximal" refers to a location on the staple 10' that is closest to the vascular access site than the portion labeled "distal". However, the nail 10' may also be considered to have a medial portion corresponding to the midline C and lateral portions extending in both directions therefrom. Thus, the position labeled "proximal" is also a medial position, and the position labeled "distal" is also a lateral position. All of these terms may be used herein.

As shown, bridge 14 is connected to each ring at an inner apex 18. In some embodiments, a bridge is connected to each internal apex, forming a closed cell structure. In other embodiments, bridge 14 is connected to every other internal apex, every third internal apex, or spaced further apart as desired, forming a variety of open cell configurations. The number of bridges 14 may be selected depending on the application. For example, six or fewer bridges 14 may be used between two rings 12 when it is desired to limit neointimal hyperplasia.

One technique for enhancing the plaque holding capacity of the bridge 14 is to align the plaque holding structure (e.g., barbs 9, tabs 10b, or anchors discussed below) with the location or direction of application of force to the ring 12. In some embodiments, at least a portion of bridge 14 may be aligned with one of the legs of ring 12. For example, when the bridges 14 are connected to the ring 12, whether at the inner apex or at the struts, the connecting portions of the bridges may extend therefrom in alignment, partial alignment, or substantial alignment with the struts. Fig. 5C shows bridge 14 connected to inner vertex 18 and shows the connecting portion of the bridge substantially aligned with strut 26. In one technique, the plaque holding structure of bridge 14 is disposed on the longitudinal axis LA projection of strut 26. As discussed below, the nail 10' has a plurality of anchors 20. Axis L_AIntersecting a portion of the anchor 20 to maximize the torque contribution from the expanded strut 26 to the anchor 20. In the configuration of fig. 5C, the anchors on opposite sides of the centerline C are disposed on the axis L_AOn the projection and mirroring the longitudinal axis L of the strut 26_AIntersects the anchor 20 of the strut on the same side of the centerline C as the strut 26 shown in fig. 5C. In another technique, the projection of post 26 and its mirror image post may be aligned with centerline C, which is rigidly coupled to anchor 20. Bridge 14 also has a high amplitude with respect to nail 10The sinusoidal portions are aligned.

As will be discussed in detail in the following sections, a unique series of design features for a variety of purposes may be integrated into the nail 10'. For example, the staple 10' may contain one or more anchors, markings, and lesion lift elements, among other features. As discussed above, fig. 5C illustrates that the plaque tack 10' can contain multiple (e.g., two) anchors 20. Staple 10' may also include position markings 22 on each bridge 14. The position markers 22 may be opaque by fluoroscopy and are typically in a flat configuration. As used herein, a flat indicia is configured to have a planar outer face that is tangent to a cylinder that extends through or is concentric with but radially disposed inwardly of the outer surface of the nail 10'. The anchor 20 may similarly be disposed tangentially to a cylinder extending through the outer surface of the nail 10'.

As another example, a unique series of design features may be integrated into the nail 10 'for dynamic distribution of stress within the nail 10'. These design features would enable uniform control of the staple 10' during compression, expansion, delivery, and catheter release. These design features may also control, individually and/or collectively, a majority of the stress throughout the staple along the struts, and at the staple and vessel lumen interface. Better control of the stress distribution within the nail is beneficial in reducing cellular response and nail breakage by limiting strut fatigue and associated micro-abrasion at the nail-vessel interface. Microabrader includes a variety of small adverse interactions between the implant and the patient's tissue, such as abrasion or abrasion that occurs at the cellular or intercellular level between the staples and the vessel lumen.

The reduction in cellular response is believed to be achieved in part by a reduction in surface area contact between the peg and the vessel lumen and in part by maximizing the alignment of the point of contact or structure with the natural orientation of the vessel cells. Thus, the staple can follow the vessel while reducing micro-abrasion. Other devices (e.g., stents) contact the vascular cells in a manner that can extend (e.g., laterally) across multiple cells, increasing microabrasion at the stent-vascular interface.

1. Single column cell design

One feature of the embodiment of the staple 10' of fig. 5A-5C is that the staple comprises a single row of open cell designs contained between two zigzag loops. This configuration provides minimal, if any, skeleton of the vessel. In one sense, the ratio of vessel contact area to total treatment area of the plaque tack 10' is very small. In this context, the vessel contact area is the sum of the outer regions of the staple 10' that may contact the vessel wall. More particularly, the vessel contact area may be calculated as the sum of all struts, the length of each strut multiplied by the average transverse dimension (width) of the radially outer surface of each strut. If the legs of the zigzag ring are laser cut, the width of the radially outer surface of the legs may be less than the width of the radially inner surface of the legs. The vessel contact area may also include the radially outer surface of the bridge 14. The total treatment area of the plaque tack 10' can be defined relative to the fully expanded configuration in the best-fit cylinder. The best-fit cylinder is a cylinder whose inner circumference is equal to the unconstrained circumference of the plaque tack 10'. The total treatment area has an area defined between the proximal and distal ends (or lateral edges) of the plaque tack 10'. The entire treatment area may be calculated as the length between the proximal and distal ends (or lateral edges) in the best-fit cylinder multiplied by the inner circumference of the best-fit cylinder. In the illustrated embodiment, the length used to determine the total footprint may be the distance at the same circumferential location between the high outer vertices of the ring 12.

In various embodiments, the ratio of vessel contact area to total treatment area is less than 50%. In some embodiments, the ratio of vessel contact area to total treatment area is even smaller, e.g., 40% or less. The ratio of vessel contact area to total treatment area may be as small as 20% or less. In particular embodiments, the ratio of vessel contact area to total treatment area is 5% or even 2% or less. As described below, the lesion lift elements may increase this advantageous feature, even further reducing the ratio of vessel contact area to total treatment area by providing separation between the vessel wall and at least a portion of the circumferential member 12.

In some methods, vessels may be treated by implanting multiple structures (e.g., plaque spikes 10'). The structure has a total contact area with the vessel wall. The total contact area may be the sum of the vessel contact areas of the individual structures. In this method, the total treatment region area may be defined as the surface area between the proximal end of the most proximal structure and the distal end of the most distal structure. In one method, the total contact area is no more than about 55% of the total treatment area. More typically, the total contact area is from about 10% to about 30% of the total treatment area. In particular examples, the total contact area is no more than 5% to 10% of the total treatment area.

The staple 10' may also be understood to provide a relatively large open area within its lateral edges as compared to the stent. Unlike conventional stents, the staple 10' need not contain enough metal to provide a skeletal function to keep the vessel open. To achieve many desired treatments, for example, the staple 10' may be configured to limit its contact to only one point or to a plurality of discrete points, such as at one or more axial locations. For example, the discrete points may be separated greatly by having the points on a circle separated by gaps or (when applied) vascular tissue.

In some embodiments, the open area bounded by the lateral edges of the staple 10', as defined above, constitutes a major portion of the total footprint. As defined above, the open area of the staple 10 'may be defined as the sum of the areas of the cells 16 when the staple 10' is in the fully expanded configuration. The open area, e.g., the area extending between the inner lateral edges of each strut, should be counted at the outer circumference of the nail 10'. In this context, the inner lateral edges are those edges that form at least a portion of the boundary of the cell 16. In various embodiments, the sum of the radially outwardly facing surfaces of the legs of nail 10 'is no more than about 25% of the open area of nail 10'. More generally, the sum of the radially outwardly facing surfaces of the legs of the nail 10 'is between about 10% and about 20% of the open area of the nail 10'. In other embodiments, the sum of the radially outwardly facing surfaces of the legs of nail 10 'is less than about 2% of the open area of nail 10'.

The single column design includes configurations in which a plurality of staple units are oriented circumferentially about the central axis of the staple 10'. The nail unit may come in various structures, but generally includes a space enclosed by the pillars and is disposed at a wall surface of the nail. Open cell designs include configurations in which at least some of the plurality of internal struts of the proximal and distal circumferential members are not connected by a bridge or axial connector. Figure 5C shows that the inner vertex 19 is not connected to the corresponding inward vertex on the mirror ring 12. Thus, a portion of the cell 16 disposed above the internal vertex 19 in fig. 5C is open to another portion of the cell 16 disposed below the internal vertex 19. The open cell design provides increased flexibility and expandability relative to a closed cell design, wherein the internal struts of each proximal circumferential member are coupled to corresponding internal struts of an adjacent circumferential member. The cell 16 is divided into two closed cells by connecting the inner vertices 19 to corresponding inner vertices on the mirror ring 12. As discussed above, closed unit plaque staples may be suitable for certain indications and may incorporate other features described herein. As shown, the single column open cell design extends along the centerline C of the bridge (and, in this embodiment, also along the circumference of the staple 10').

In one embodiment, the cells 16 and a plurality of additional cells 16 to be disposed circumferentially about the central axis of the nail 10' are identical. The number of cells may vary depending on the following factors: such as the size of the vessel or vessels in which the staple 10' is constructed, the preferred configuration of the ring 12, the number of bridges 14 to be provided, and other factors.

As described above, the staple 10' may include proximal and distal rings 12 connected by a bridge 14. A proximal ring 12 may be provided at the proximal end of the nail 10'. A distal ring may be provided at the distal end of the staple 10'. In some embodiments, the distal ring is the most distal position of the staple 10 'and the proximal circumferential member is the most proximal position of the staple 10'. The bridge members 14 can divide the outer surface of the staple 10' into cells 16 bounded by the bridge members 14 and a portion of each of the proximal and distal rings 12. In the embodiment of fig. 5A-5C, a single column design is provided by providing a bridge at only one axial location and only a pair of circumferential members or rings 12. Fig. 5C contains the terms "distal" and "proximal" for reference purposes in relation to this and other examples, and thus the illustrated ring 12 is a distal ring. In other embodiments, the illustrated loop 12 may be a proximal loop.

As noted above, the cells 16 may have one of a number of different shapes and configurations. FIG. 5B shows the cells 16 aligned as a repeating pattern, forming a single column of open cell designs along the circumference of the staple 10'.

Conventional stent designs are typically relatively long from their distal to proximal ends (e.g., 4cm, even up to 20cm when used in peripheral vessels). When circumferentially arranged cells are deployed, conventional stents have a large number of rows of cells. These designs bear repetitive weak points and can create stresses that become unmanageable. These conventional stents must find a more flexible region within the strut matrix once the device is under stress and tension. These strut regions absorb the load of the entire system and begin to fail under cyclic repeated external forces, such as through metallurgical friction loading.

The single-file configuration of the staple 10' is not subject to repeated weak point loading due to movement of the remote stent portion, as the staple does not have to be axially elongated to provide an effective stapling treatment. Other benefits stemming from the short length include reduced friction at the interface with the catheter sheath and at the interface with the vessel wall during delivery. As described above, the lack of cell-to-cell drag or pulling reduces stress at the vessel wall interface, thereby reducing the potential problem of the staples pulling or dragging adjacent cells to increase the inflammatory or histological response along the lumen wall. The single column or other axially short configuration also reduces stress along each strut because the entire length of the single column or other axially short structure or configuration is not affected by anatomical motion (e.g., bending, twisting, and rotation). This is at least partly due to anatomical deflection around short structures, whereas longer structures do not allow anatomical deflection and therefore absorb more of the forces generated by anatomical movement.

Any movement between the surface of the nail and the blood vessel can cause abrasion and friction. As mentioned above, if the motion is very small, it can be described as micro-abrasion. Even micro-abrasion negatively affects both the nail 10' and the biological cells of the blood vessel. For example, friction occurs when one part of an implanted object moves while another part is stationary or moving a small amount. Over time, the differential amount of motion weakens the material, resulting in fracture through processing (e.g., work hardening). Biological cells are subjected to frictional stimuli and can respond by producing an inflammatory response. Inflammation can drive a variety of undesirable histological reactions including intimal hyperplasia and restenosis.

2. Controlled strut angle

Fig. 5C shows a nail 10' having two circumferential members or rings 12 each having a plurality of interior angles comprising alpha and sigma. A first angle alpha is defined at a first outer apex 24 between strut 26 and strut 27, and a second angle sigma is defined at an outer apex 25 between a second strut 28 and strut 29. In some embodiments, the first angle α may be greater than the second angle σ. For example, the first angle α may be between 43 ° and 53 °, or between 45 ° and 51 °. The second angle σ may be between 31 ° and 41 °, or between 33 ° and 39 °. In some embodiments, the first angle α may be about 48 °, and the second angle σ may be about 36 °.

In a preferred embodiment, the nail 10' has an expanded outer diameter of 7.5mm, and the first angle α may be 47.65 ° and the second angle σ may be 35.56 °. In such embodiments, the plaque tack 10' may be formed from a tube stock having an initial outer diameter of 4 mm. The tube stock may be expanded to 7.5mm and then heat treated in that shape. In some embodiments, the plaque tack 10' can be made of a shape memory material, and the heat treatment step can root its particular shape into the "memory" of the material. The plaque tack 10' can then be crimped or compressed and snap frozen in the compressed state and then loaded onto a delivery device.

An advantageous feature of the nail 10' is that, as the struts intersect each apex, the angle of the struts can be controlled in at least one of the expanded state and the contracted state. For example, the internal angles α, σ of the outer vertices 24, 25 may be controlled to within ± 5% of a selected nominal value. Such control may be achieved, for example, in the expanded state during thermal treatment during the manufacturing process of the plaque tack 10'.

It has been found that control of the angle can advantageously provide mitigation of defects from the manufacturing process. In some cases, if these angles are controlled sufficiently well, control of other dimensions may be relaxed. By controlling these angles, production run quality can be improved. Such control has been found to produce repeatable, uniform and uniform compressibility of the nail 10' during the crimping cycle of manufacture. These factors increase the repeatability of the production run and ease of mass production, which in turn results in a reduction in the overall cost of the component.

In addition, control of the apex angle allows the plaque tack 10' to better distribute stresses along the circumferential member or ring 12. For example, control of the apex angle may be used to control or distribute the stresses within the ring 12 evenly along the length of the strut, or unevenly to regions that may be more robustly responsive to stress loading. By distributing the stress along the struts, problematic local stresses on the nail 10' (e.g. at weak points) can be avoided during the expansion and crimping process of manufacture.

3. Reverse tapered strut

In some embodiments, such as shown in fig. 5A-5C, the width of one or more struts 26, 27, 28, 29 of the staple 10' can be different at different locations, e.g., can vary along the struts. For example, the struts may be tapered along their length. The taper along each strut or along each type of strut may be the same or different. For example, each circumferential member or ring 12 may be constructed of a pattern of repeating struts, with each type of strut having a particular taper.

Fig. 5C shows that ring 12 has a first leg coupled to bridge 14 that is tapered such that a portion of the leg near midline C (sometimes referred to herein as the medial portion or location) is narrower than a portion of the leg away from midline C (sometimes referred to herein as the lateral portion). The second strut is connected to the first strut at lateral ends of the first and second struts. The second struts may have the same or different tapers. For example, the second leg can also have a medial portion that is narrower than a lateral portion of the second leg. Additionally, the second leg may be generally narrower than the first leg. The third strut may be connected to the second strut at an intermediate end of the second strut and the third strut. The third strut may have a medial portion that is wider than lateral portions thereof. The fourth strut may be connected to the third strut at lateral ends of the third strut and the fourth strut. The fourth strut may have a medial portion that is wider than lateral portions thereof. The fourth leg may have the same or a different taper than the third leg. For example, the fourth strut may be wider overall than the third strut.

Figure 5C schematically illustrates the difference in strut width in one embodiment. In some embodiments, long struts 26 and long struts 27 have the same width at the same axial position, and short struts 28 and short struts 29 have the same width at the same axial position. The pillars 26 and 27 may have the same shape. Struts 28 and struts 29 may have the same shape in some embodiments. The shape of the struts 26, 27 may be different from the shape of the struts 28, 29. In some embodiments, long struts 26 and long struts 27 have different widths at the same axial position, and short struts 28 and short struts 29 also have different widths at the same axial position.

In the preferred embodiment, the long legs 26, 27 are disposed at a first circumferential location of the nail 10' adjacent one of the markings 22. In particular, the struts 26 have a medial end connected to or forming part of one of the internal vertices 18, and a lateral end disposed away from the internal vertices 18. The lateral ends are coupled to the struts 27 at the outward apices 24 or at adjacent outward apices 24. The strut 26 has a width W4 adjacent the medial end and a width W2 adjacent the lateral end. In this embodiment, the width of the strut 26 increases along its length from a width W4 to a width W2. The increase in width along the strut 26 is preferably continuous along the length.

Furthermore, the sides of the strut 26 are relative to the longitudinal axis L of the strut 26_AMay be inclined. For example, first side 48 disposed between the longitudinal axes of struts 26 and 27 may be disposed at an angle to the longitudinal axis of strut 26 (e.g., not parallel to the longitudinal axis of strut 26). In another embodiment, the second side 46 of the strut 26 may be disposed at an angle to the longitudinal axis of the strut 26 (e.g., not parallel to the longitudinal axis of the strut 26). In one embodiment, both the first side 46 and the second side 48 of the strut may be disposed at an angle to the longitudinal axis of the strut 26.

The struts 27 also preferably have different widths at different points along their length. In particular, struts 27 may generally widen in the lateral direction, being wider adjacent outer apices 24 than adjacent inner apices 19. As discussed above in connection with strut 26, strut 27 may have sides that are angled with respect to the longitudinal axis of strut 27. The strut 27 may be tapered between its ends, for example having a width that continuously decreases along its length from a wider portion adjacent the outer apex 24 to a narrower portion adjacent the inner apex 19.

The struts 28 extend from the struts 27 or the inner apices 19. The posts 28 have medial ends that are wider than the lateral ends of the posts 28 and have different widths at different points along their lengths. The side surfaces may also be angled relative to the longitudinal axis of the strut 28.

Finally, the struts 29 may be connected to the struts 28 or the outer apices 25 at the lateral ends of the struts 29. The strut 29 may have a medial end that is wider than its lateral ends. The taper of the strut 29 may be the same or different than the taper of the strut 28. For example, the strut 29 may be wider than the third strut as a whole.

In one embodiment, the width W of the strut 26 at the lateral end near the outer apex 24₂Is about 0.12mm and a width W at the middle end near the inner apex 18₄Is about 0.095mm, and the width W of the strut 28 near the outer apex 25₆Is about 0.082mm and has a width W near the inner vertex 19₈Is about 0.092 mm. More generally, the thickness variation, expressed as a percentage, between W4/W2 is between about 70% and about 90%, more typically between about 75% and about 85%, and in certain embodiments about 80%. The taper may also be reversed, for example, with the struts tapering from the end portions (e.g., lateral edges) toward the middle portion.

Fig. 5E shows another variation, in which the width of one or more struts of the staple is different at different locations, e.g., may vary along the strut. For example, a strut 28 'similar to strut 28 may be provided, except that strut 28' is narrowest in the middle N. The strut 28' has a lateral wide portion L adjacent the outer apex 25 and an intermediate wide portion M adjacent the inner apex 19. The width of the strut 28' decreases along its length from the laterally wide portion L toward the intermediate portion M. In one embodiment, the struts 28 'continuously narrow along the length from the lateral ends of the struts 28' toward the midline of the struts. The struts 28 'may narrow such that the ratio of the width at the midline of the struts 28' to the width at the lateral ends, expressed as a percentage, is between about 20% to about 85%. In some embodiments, this percentage is between about 35% to about 75%. The tapering may be such that the percentage is between about 55% to about 70%. The strut 28' may narrow from a wide middle portion along its length. In one embodiment, the struts 28 'continuously narrow along the length from the medial ends of the struts 28' toward the midline of the struts. The struts 28 'may narrow such that the ratio of the width at the midline of the struts 28' to the width at the medial ends, expressed as a percentage, is between about 20% to about 85%. In some embodiments, this percentage is between about 35% to about 75%. The tapering may be such that the percentage is between about 55% to about 70%. The embodiment of fig. 5E provides greater range for compression and expansion in smaller diameter configurations. The smaller diameter configuration may be used for smaller body lumens (e.g., blood vessels). For example, a staple having this configuration may be formed from a 2.3mm diameter tube, while the embodiment of FIG. 5C is best formed from a 4.5mm diameter tube. The configuration of fig. 5E may be used to prepare staples suitable for a 4 French delivery device. Staples constructed as in fig. 5E may have an unconstrained expanded size of between about 4.5mm to about 6.5 mm. In some embodiments, a device comprising the configuration of fig. 5E may have an unconstrained expanded size of between about 5mm to about 6mm (e.g., between about 5.5mm to about 6.0 mm). When not constrained, one embodiment expands to about 5.7 mm.

The unique reverse taper or width variation along the struts can be achieved by reversing the direction of the taper between the short struts 28, 29 and the long struts 26, 27. The longer struts 26, 27 go from a narrow width near the inner 18, 19 apices to a wider width near the high outer 24 apices. Conversely, the shorter struts 28, 29 are relatively wide from the wider width near the inward apex 18, apex 19 to the narrower width near the lower outward apex 25.

As discussed above, by strategic selection of the width of the struts, the plaque tack can distribute the stresses observed during compression and subsequent deployment. This feature also aids in stress control by distributing the stress regions more evenly along the length of the strut. In some embodiments, it may be desirable to distribute the stress unevenly to the regions to be more able to handle the stress.

4. Double-amplitude strut

As discussed above, the ring 12 shown in fig. 5A-5C has an undulating sinusoidal pattern. The axial extent of the ring 12 may vary around the circumference of the ring 12, for example by providing a plurality of amplitudes measured from the inner apex to the adjacent outer apex. The undulating pattern may have one or more amplitudes, as shown in the double amplitude configuration. In the dual-amplitude configuration, a plurality of struts 26, 27, 28, 29 extend between the inner 18, 19 and outer 24, 25 apices.

In some embodiments, the exterior apices 24, 25 alternate between high exterior apices 24 and low exterior apices 25. "high" in this context corresponds to a greater distance H1 measured from the central region or centerline of staple 10', and "low" corresponds to a lesser distance H2 measured from centerline C (FIG. 5C).

The varying amplitudes of the long and short sinusoidal struts described above may provide additional control over the functionality of the plaque tack 10'. In particular, the magnitude of the change may increase the compression of the nail 10' to provide a greater change in circumference from the fully expanded configuration to the compressed configuration when crimped during manufacture. Greater compressibility facilitates delivery in smaller vessels and a greater range of indications that can be treated, as greater compressibility enables smaller cross-distributed delivery systems.

The heights H1, H2 of the vertices are measured from the centerline C to the top of the respective outer vertices 24, 25. As shown in fig. 5A-5C, a dual amplitude sinusoidally patterned plaque tack 10' enables a wide range of suitable sizes that can be easily expanded to different outer diameter designs. The open cell single column design allows for a wide range of compression and expansion. This is due in part to the length of struts available for effective expansion. The ease of compression associated with the placement of the apices at positions H1 and H2 from the center of the nail allows the apices to be compressed at different positions rather than at the same lateral position. If the apexes H1 and H2 are aligned (e.g., at the same axial position), the apexes will press against each other during compression, limiting the compression range.

Albeit with mottleThe range of compression of the block staple 10' has been measured as 0.25 times the nominal tube size combined with a range of expansion up to 2 times the nominal tube size, but these are not the intended limits of the device. In conjunction with these ranges, the total range of compression has been measured as 0.125 times the outer diameter of the heat treatment. As discussed above in section ii.b.2, in some embodiments, the nominal tube size is 4.5mm and the tube expands to 7.5mm in the manufacturing process. According to some embodiments, the distance H from the midline C of the device to the apex of the longer strut₁About 3.0mm and a distance H from the midline C of the device to the apex of the shorter strut₂Is about 2.6 mm. In some embodiments, H₁Approximately equal to H₂Or, H₂Is H₁About 1/2 or more, or about 3/4 or more. In some embodiments, H₁Between about 1.0mm and 8.0mm, or between about 2.0mm and 6.0mm, or between about 2.0mm and 4.0 mm.

In addition to the enhanced range of compressibility, the energy stored in the shorter amplitude struts provides additional control of the plaque tack 10' during the release phase of intravascular delivery. As the catheter sheath is withdrawn, the longer struts are uncovered first, followed by the shorter struts (fig. 5C). This mismatch provides greater retention to maintain the plaque tack 10' in the delivery catheter and thus greater control of the plaque tack during delivery.

Figure 5F illustrates another embodiment of a plaque tack. In this embodiment, the inner vertex 19 "is disposed outwardly a distance H from the inner vertex 18₃At the location of (a). Thus, it can be seen that struts 27 "and struts 28" are similar to struts 27 ', struts 28', except that they are relatively short. This configuration provides additional benefits, particularly in delivery. Although the plaque tack of fig. 5F is shown with four struts of different lengths and outer apices 25, 24 spaced apart from the bridge member by different lengths, it should be understood that the tack may be otherwise configured. For example, struts 28 "and 27" may have the same length and outer apices 25, 24 may be the same distance from the bridge member, while struts 26, 2729 may be longer.

In some embodiments, length H₃May be no more than about 5%, 7%, 10%, 25%, 30%, 40%, 50%, or 75% of the length of strut 26 or strut 29.

As already mentioned, plaque tacks can be delivered in a highly controlled manner. Different lengths of struts and different locations of the apex may help facilitate controlled release of the staples. When released from the delivery device, the struts of different lengths expand at different rates such that the energy stored in the struts is released in stages rather than in a single release. As has been discussed previously, varying the width of each strut can also help control the storage and release of energy. Inner vertex 19' inner vertex 18 has a distance H from the inner vertex₃It also helps to release the stored energy more evenly over time. As mentioned above, the distance H is compared to the length of the strut₃May be a large distance or a relatively small distance. In addition, once the internal apex 19 "is released, the pad or foot 21 is exposed (see fig. 5F and 5G). The foot 21 may be formed by an inner apex 19 "and two struts 27", 28 ".

The legs 21 may reach the first expanded state once the struts from the first loop have been released from the delivery device. This may result in a series of legs 21 extending annularly around the plaque tack. These series of legs can help the plaque tack to be delivered with high precision because the legs can be in a position parallel to the vessel wall. The legs 21 may have a pre-full deployment diameter that is less than the full deployment diameter. After the remainder of the staple is released, the legs can move into contact with the vessel wall in a rapid manner, minimizing the movement of the plaque staple. The legs are parallel to the vessel wall when the staple is released, which can help reduce or prevent point pressure on the vessel wall. This may reduce irritation or other undesirable problems. This configuration may also reduce common problems in stents, such as scraping or dragging of the device along the vessel wall as the device is released. This problem typically occurs in stents because the stent is released and the device struts engage the vessel wall at an angle.

In some embodiments, legs 21 will be almost fully expanded while the majority of the remaining plaque tack remains constrained within the deployment catheter.

In other embodiments, the legs can be released to the first expanded position, and then the legs can be moved to the intermediate expanded position prior to releasing the staples. For example, length H₃May be a relatively large distance so that the foot will be released before the majority of the length of the legs 26, 29 is released. This type of configuration may be used with a relatively large vessel or space within an organ.

Legs 21 may also help center the delivery device and/or prevent rotation of the plaque tack. When the guidewire is used with a delivery device, the natural bend in the vessel may be offset from the guidewire and thereby cause the delivery device to face one side of the vessel. In one extreme example, the delivery device may be placed on the vessel wall. The released legs may force the staples and the delivery device away from the vessel wall. This is because as the legs are released to the expanded state, the expansion of the device allows the legs to contact the vessel wall and push away from the vessel wall to begin centering the staple and delivery device. Even if the forces on the delivery device do not allow the delivery device to be centered by the legs, the legs may control the release and positioning of the staples so that the staples will be properly positioned and centered in the vessel. The legs can center and properly align the plaque tack with the vessel wall in a direction other than independent of the delivery device.

The feet typically center the device for a short period of time, such as during one phase of delivery. This time period may be as long as the halfway point of delivery, e.g. until the bridging member is released. In addition, the legs typically center only a small portion of the delivery device. For example, the feet may center about 3mm to 5mm of the delivery device, with about 3mm to 5mm on either side of the feet.

It should be understood that although the legs are shown with respect to the staples, this concept is also applicable to other devices including stents, vascular implants and other types of implants.

In fact, the device can undergo a significant reduction in axial length, as device expansion also helps to promote proper placement. For example, in some implementations, the plaque tack may be shortened by at least about 15%, at least about 20%, at least about 40%, or more before the entire device has been in contact with the vessel wall and reached the deployed length. The deployed plaque tack may be less than twice the vessel diameter in length.

In some embodiments, the axial length of the staples after unconstrained expansion is no more than about 95%, in some cases no more than about 90%, in some implementations no more than about 85%, in some cases no more than about 75%, and in some cases no more than about 60% of the axial length of the staples when compressed within the delivery catheter. For example, a 5mm to 6mm staple may experience a shortening of at least about 1 mm.

In some embodiments, the length of one or more struts may be increased to increase the stability of the device. For example, struts 26, and/or struts 29 may be lengthened relative to the previously described embodiments. The length of the struts may be between about 4mm and 10mm, or between about 6mm and 8 mm. In addition, the number of undulations (nulls) and/or bridges may vary depending on the size of the artery in which the plaque tack is desired. For example, a staple intended to be deployed via a3 french device may contain three or four bridge members, while a staple intended to be deployed via a 6 french device may contain up to 12 or more bridge members. Thus, in some embodiments, the plaque tack may have six cells. Other numbers of cells may also be used. Fig. 5H-5J illustrate certain examples of staples in which the undulations of the loop have been modified. In these embodiments, additional and/or larger feet are created by the modified waves. In some embodiments, additional and/or larger legs may be gradually expanded such that the first set of legs 21A is released before the second set of legs 21B.

Herein, as disclosed herein, include those shown in fig. 5A-5J, but are not limited toIn many other plaque staples of these embodiments, controlled expansion and delivery of the staples may be further facilitated by the formation of a hinge 23 between the ring and bridge 14 (see fig. 5G). Hinge 23 is effectively located at the junction between the inner vertices 18 where the ring is connected to bridge 14. The hinge 23 allows the individual rings to expand and contract individually and to be spaced apart from the bridges, other rings and devices as a whole. As described, when the struts have different lengths, the hinges 23 in combination with other features of the nail can expand the struts at different rates and can also allow the legs 21 to expand out separately from the rest of the nail. In addition, as will be described in greater detail herein, the hinge also imparts a distraction force on the bridge and thus on the anchor 20, such that the anchor is secured to the sheath to secure the plaque tack within the delivery device during delivery, even being released as part of the plaque tack. The inner vertex 19 "may be located at a distance H from the inner vertex 18₃Sufficient to allow the inner apex 19 "to release while the anchor drills into the sheath to hold the inner apex 18 closer to the sheath. This distance may be a very small or large distance. Further, in certain embodiments, the distance may be zero, or the inner vertex 18 may be spaced further from the anchor 20 than the inner vertex 19 ". In a preferred embodiment, as shown in fig. 5F, the internal apices 19 "are spaced outwardly relative to the anchor 20 by the internal apices 18.

Another benefit of the post configuration and bridge of the plaque tack is that one size of plaque tack can be used with many different sizes of vessels. The implanted staples can be expanded to one of an almost infinite number of sizes between a compressed state and a fully expanded state. For example, in some embodiments, a 4 french plaque tack may be used in arteries of 1.5mm to 4.5mm, a 6 french device may be used in arteries between 3.5mm and 6.5mm, and a 5 french device may be used in arteries between 2.5mm and 5.5 mm. In some embodiments, a 5 french device may be used within an artery of 2.5mm to 6.5 mm. It will be appreciated that the length of the struts may be varied to increase or decrease the range of vessel sizes in which the staples may be deployed.

In some embodiments, the staple has a proximal leg 21, a distal leg 21, and an intermediate section. Distal leg 21 is expandable to conform to the interior of a cylinder or vessel wall while proximal leg 21 remains within a deployment catheter or other delivery device. Distal leg 21 may be at least about 1mm, and in some embodiments at least about 2mm or at least about 3mm, but typically does not exceed about 5mm and is typically less than about 4mm in axial length. The proximal leg may be symmetrical to the distal leg about the axial midpoint of the nail. In some embodiments, the staple has a distal leg 21 but no proximal leg.

Another advantage of the plaque tack design can be seen when comparing its use in different sized vessels. As the size of the vessel decreases, the ratio of the size of the staple to the diameter of the vessel increases, but the struts are more aligned with the longitudinal axis of the vessel. This helps to reduce the amount of staples or the amount of strut area in contact with different cells of the vessel wall. This is because many of the blood cells of the vessel wall are also longitudinally aligned. Thus, for a given size of staple, as the vessel size decreases, the orientation of the struts will more closely align with the orientation of the cells that make up the vessel wall. Thus, this configuration helps reduce contact of the struts across isolated cells, thereby reducing abrasion, irritation, and other inflammatory cellular responses. The orientation of the struts can be seen by comparing the position of the struts in fig. 7B with fig. 7D. It will be appreciated, however, that the plaque tack in its fully expanded state also greatly reduces the likelihood of adverse cellular reactions compared to other known devices as already explained above.

5. Centrally disposed anchor and lifting structure

Figures 5A-5C illustrate that the plaque tack 10' can contain a centrally disposed anchor 20. As noted above, while the anchoring elements 20 are primarily used to secure loose plaque, their placement and configuration enhances control of deployment and performance of the staple 10' when deployed inside a blood vessel.

As described above, the plaque tack 10' can be a self-expanding circumferential structure and the anchors 20 can be disposed on the exterior of the tack. The anchor 20 may be coupled to any portion of the nail 10', but is preferably disposed adjacent the midline C of the bridge 14 as described above. In one embodiment, as shown in fig. 5C, the staple 10' includes two anchors disposed on either side of the midline C. In another embodiment, a single anchor may be provided on the midline C. In yet another embodiment, at least three anchors 20 may be provided, for example one on the midline and two on either side of the midline C, as shown in fig. 5C. As shown in fig. 5D, the bridge 14 may have two anchors on one side and one anchor on the other side connecting the two other anchors. In fig. 5D, the anchor 20 'is located in the center of the nail 10' in its axial direction. The present embodiment provides at least one anchor 20' on both sides of the midline C. Additionally, the anchor 20' may be located on the opposite side of the indicia 22 from the anchor 20. As such, the plaque may be fixed from multiple directions, for example, from multiple circumferential directions. In another embodiment, the anchor 20 is absent, and a single anchor 20' located on the midline C is provided. The embodiment shown in fig. 5A-5C may also be modified to include one or more anchors on either side of the marker 22, with anchors now shown on only one side.

In one aspect, the plaque with which the staples 10' interact is provided primarily by the anchors 20 and to a lesser extent by the bridges 14. In some embodiments, the length of the anchors that penetrate into the plaque may preferably be 0.01mm to 5 mm. In certain variations, the penetration length is in the range of about 0.03mm to about 1 mm. In other variations, the penetration length is in the range of about 0.05mm to about 0.5 mm. As described above, when the staple 10' is fully expanded and is not deformed by the outward configuration, the bridges 14 disposed at alternating inward apices can be configured to reside in the tangential plane of the cylinder. The tangential configuration causes the anchor 20 to project outwardly from the cylindrical surface of the nail 10'. At this outwardly protruding position, the anchoring elements are adapted to engage a plaque or other vascular deposit that causes the blood vessel to change from its unobstructed, fixed state to, for example, an out-of-round.

The tangential projection of the bridge and anchor also advantageously enhances control of the staple 10' during deployment. Techniques for deploying the staples 10' include positioning the staples in a hollow catheter body. When the staple 10 'is in the catheter body, the staple 10' is compressed to a compressed state. As discussed above, the ring 12 is highly conformable due to its structure. Thus, the ring is fully attached to the luminal surface of the hollow catheter body. Conversely, the bridge 14 and anchor 20 are more rigid and therefore less conformable and therefore penetrate the luminal surface of the catheter body. This creates a retention force within the catheter and limits unintended movement of some or all of the staples 10' to the catheter deployment area.

In some embodiments, the retention of barbs 20 is maintained or increased after partial deployment of staple 10'. In particular, a region of relatively high flexibility may be provided at the junction of the bridge 14 and the ring 12. While high flexibility of the stent may be a region of interest, this is not the case with the plaque tack 10' for reasons discussed below. The pliable region may have any material property or structure that enhances its flexibility at least as compared to the bridges 14 so that the tangential configuration of the anchors 20 and the tendency to penetrate into the hollow elongate catheter body is not diminished as the loop 12 is moved over the deployed leading edge. Even though the leading edge ring 12 may expand to at least half its full expansion size.

As shown, a bridge 14 is connected to each ring at an inner apex 18, wherein at least a portion of the bridge 14 may be aligned, partially or substantially aligned with one of the struts making up the ring 12 as already described. For example, as shown, bridge 14 is aligned with a high amplitude sinusoidal segment of the pattern. A region of relatively high flexibility may be provided between the inner apex 18 and the bridge 14.

In some embodiments, expansion of the ring 12 may even cause the anchors 20 to rotate outward to improve retention in the catheter body. For example, expansion of the struts 26 may cause the inner apices 18 to deflect inwardly. As the loop 12 expands, a slight rotation of the anchors 20 can occur, which will result in an outward torsional deflection of the leading anchor and a corresponding outward torsional deflection of the trailing anchor. Referring to fig. 5C, if the depicted loop 12 is first expanded upon removal from the hollow catheter body, the anchors 20 to the right of the midline C may be deflected inward toward the central axis of the catheter body while the anchors 20 to the left will be deflected outward to increase their retention. Thus, the plaque tack 10' may be retained in the catheter during such partial expansion. As discussed further in section ii.b.8 below, due to this feature, the plaque tack 10' can be placed evenly.

The out-of-cylinder nature of the bridge 14 and anchor 20 also facilitates the deployed state. In particular, in some embodiments, in the expanded state, the plaque anchors 20 are disposed radially outward of the surface of the cylinder formed by the ring 12. The extent of the protrusion beyond the cylinder may depend on the application, but is generally sufficient to space at least a portion of the surface of the cylinder from the inner wall of the vasculature when deployed. In this way, the anchor 20, or anchors associated with the ring 12, may be configured as a focal elevating element, as will be discussed in section III below.

As the plaque tack 10' expands within the vessel, the struts will engage the vessel wall and/or plaque. It is anticipated that in most cases at least some of the struts will deform in response to irregularities in the shape of the blood vessel. At the same time, the bridge 14 is less deformable and will therefore maintain a circular configuration against such deformation. The outward force applied by the strut members is transmitted to those areas in contact with the vessel wall. In some cases, when the staple 10' conforms to an irregularly shaped vessel lumen, the rigid central anchor becomes an area for contact with the vessel. The outward force built up by the struts in the ring 12 is applied to the anchor via the bridges 14. The adjacent struts share their load with the contact area pressing the vessel into an enlarged configuration (e.g., a compliant circle).

This configuration may provide the following advantages: for example, to help the plaque tack 10 'remain in place after delivery and to allow the plaque tack 10' to dynamically respond to the motion and pulsation of the vessel wall itself. Furthermore, such a configuration may have the following advantages: cellular response and device breakage are reduced by limiting strut fatigue and associated microabrader loading at the staple-vessel interface.

In some embodiments, the bridge 14 can include one or more anchors. In some embodiments, the bridge may be formed entirely of the anchor.

In some embodiments, the plaque tack 10' has a generally cylindrical shape. For example, the plaque tack 10 'can be cut from a metal tube such that the plaque tack 10' retains the features of a generally curved top surface. Thus, in some embodiments, the bridge 14 and one or more anchors 20 are also curved with the rest of the top surface of the staple. Thus, the anchor may remain in-plane with the remainder of the top surface even as the device moves between the expanded and compressed configurations. In some such embodiments, the anchor is forced out of the plane when the staple is expanded into a non-circular portion of a vessel (typically in a diseased artery or other vessel). Due to the flexibility of the staples, certain portions of the staples may be forced into a non-circular configuration through a diseased portion of the vessel. As a result, one or more anchors at the portion may protrude outward and engage the vessel, while other anchors may not extend outward or out of plane. Since it is generally difficult to know where the diseased portion of the vessel will be, in certain embodiments, the bridge at each cell may contain at least one anchor at or near the centerline of the staple. Other configurations are also possible.

After deployment of the plaque tack 10', the surgeon may choose to place an angioplasty balloon at the site of the tack and inflate the balloon to compress the one or more anchoring elements 20 into the plaque and/or vessel wall.

6. Flat midline marking

As described above, the plaque tack 10' has one or more markers 22. In one embodiment, a series of radiopaque markers 22 may be located on the nail 10'. In some embodiments, the radiopaque marker 22 is at the midline C of the device. The radiopaque marker 22 may be disposed between two circumferentially oriented sinusoidal members or rings 12.

In some embodiments, a radiopaque marker 22 (e.g., platinum or tantalum) may be disposed adjacent to the plaque anchor 20. The radiopaque markers 22 may have one of a number of different shapes or configurations. In some embodiments, the radiopaque markers 22 have a planar or flat configuration. As shown in fig. 5C, each indicium 22 couples with a circular eyelet, such as by stitching or riveting, to create a flat horizontal surface with an eyelet. The markings 22 provide the staples 10' in the catheter delivery system with clear visibility and provide the clinician with guidance for accurate placement during surgery.

According to certain delivery methods, since the anchor 20 and marker 22 are co-located at the bridge 14 between the sinusoidal rings 12, it will happen that the marker 22 can provide visual clues to the clinician in the field when the device is released. For example, when the marker 22 encounters a marker band located at the tip of the delivery catheter sheath, the entire device may be deployed.

Referring now to FIG. 5C1, a schematic view of staple 10' is shown. As shown, the anchor 20 has an increased material thickness relative to the remainder of the nail. This results in the anchor 20 also having increased radiopacity as compared to the rest of the nail, effectively converting the anchor into a marker.

7. Synchronization device placement in a vessel

The plaque tack 10' can be configured for simultaneous placement within a blood vessel. Simultaneous placement of the plaque tack 10 ' can be defined as the entire plaque tack 10 ' being released from the delivery catheter before any distal apices of the plaque tack 10 ' contact the lumen of the blood vessel in which the plaque tack is to be placed. This event can occur when the anchor 20 is completely uncovered by the catheter sheath, allowing the entire plaque tack 10' to expand against the luminal wall of the vessel. Struts 26, 27, 28, 29 may be free floating, e.g., spaced from the vessel wall or exert negligible force against the wall so that they do not contact the lumen wall prior to simultaneous placement. For example, the anchor 20 may have the effect of spacing some or substantially all of the struts 26, 27, 28, 29 from the vessel wall. Other forms of focal elevating elements that may be used to space the staple 10' from the lumen wall will be discussed below.

Synchronized placement provides the clinician with the ability to control placement until the marker 22 and/or anchor 20 are uncovered, which can result in a full expansion event (struts adjacent or contacting the luminal wall). In some embodiments, the full expansion event does not occur until the anchor 20 is caused to be uncovered, primarily due to the internal force of the staple 10' pushing the anchor 20 into engagement with the delivery sheath as described above.

Another benefit of synchronized placement is to reduce any inadvertent dragging or pushing against or along the luminal surface during placement of the plaque tack 10'. Due to the complexity and variation of the condition, the location of placement, and the anatomical morphology, the ability of the outer surface of the plaque tack 10' to contact the lumen wall at the same time depends on the deployment. However, the ability of the plaque tack 10' to fully contact the lumen wall within a fraction of a second after release from the catheter sheath has been observed.

8. Low slope force curve

Another unique aspect of the plaque tack 10' is: the plaque tack may be configured with a force curve having an expanded region with a low slope. Force profiles (such as those shown in figure 6A) show the amount of expansion force exerted by or on the self-expanding plaque tack 10' or stent when moving between the compressed and expanded states. The expansion force of the device may be a factor in selecting the correct device to be placed into a particular vessel.

Still referring to fig. 6A, SMART stent (i.e., manufactured by Cordis corporation)Stents for controlling the passage of the skin and liver through the biliary tract) and bagsForce profiles for two different sized plaque pins including plaque pins having the wall pattern shown in figure 5A. The graph shows the radial force in newtons (N) on the y-axis and the outer diameter of the device in millimeters (mm) on the x-axis. As the device expands or moves from the compressed state to the expanded state, the outer diameter increases. Since the device is self-expanding, the device has a set of stored potential energy quantities. When released, the potential energy is converted to kinetic energy as the internal forces attempt to return the device to its expanded shape. The kinetic energy can then cause an impact on the vessel when the device is implanted. Additionally, if the plaque tack 10 'is not fully expanded, a substantially constant force corresponding to the residual potential energy stored in the tack 10' will be applied to the vessel wall.

FIG. 6A shows first line A1, first line A1 showing the compression of 4 French plaque tack 10' from a compressed diameter of about 5.5mm to 1.5 mm. After a gradual slope region between about 5.5mm and about 4.5mm, the slope of the force decreases rapidly for each incremental decrease in diameter, providing a narrow band of force required to fully compress the staple 10' from about 5mm to about 1.5 mm. This portion of the force curve is very flat, meaning that the applied compressive force does not increase greatly as the nail 10' approaches its fully compressed state. The force curve of the plaque tack 10' when expanded, second line B1, shows that B1 extends from a compressed diameter of 1.5mm to an expanded diameter of about 5.5 mm. This portion of the curve may be considered the working portion, where the force in the Y-axis is the force applied to the vessel wall by the plaque tack 10' when expanded. For example, if the plaque tack 10 ' is deployed in a vessel lumen having an inner diameter (bore) of about 4.0mm, the outward force of the tack 10 ' on the wall 10 ' is on the order of 1.0 newton (N).

Also shown are 6 french plaque pegs as indicated by lines a2 and B2. The 6 french nail shown is compressed from a diameter of about 7.5mm to a diameter of about 3.0 mm. The 6 french nail shows a force curve very similar to the 4 french device, with a slight offset reflecting the difference in diameter. The force (line a2) of the compression device shown herein is between about 7.5mm and 6.0mm with a gentle slope area, which is then very flat between about 6.0mm and 3.0 mm. The 6 french nail also exhibits low outward radial force when shown expanded by line B2. The force profile of a 6 french plaque tack is shown between about 2.0mm diameter and about 7.5mm diameter when expanded. It can be seen that if a 6 french plaque tack is deployed in a vessel lumen having an inner diameter of about 5.0mm, the outward force of the tack on the wall will be less than 1.0 newton (N).

Fig. 6A also shows the crimping performance of the SMART stent in a similar test at lines a3 and B3. As discussed above for other prior art stents, the SMART stent is a structure that is longer than the plaque tack 10'. In particular, testedThe stent was 40mm long with an unconstrained outer diameter of 8mm, while the 6 french nail tested was 6mm long with an unconstrained outer diameter of 7.5 mm. However, it is believed that the comparison between the plaque tack and the SMART stent shows a difference which would still indicate a difference from a comparable length version of the SMART stent. As shown, line B3 shows that a greater force is required to compress the SMART stent in the range of just over 8mm to about 6.5 mm. At about 6.5mm, the slope of the compression or crimping force decreases and then increases at a much slower rate. The outward force in the fully crimped state is much higher than the force measured in the plaque tack. Line B3 shows the working area of the SMART stent under test. Line B3 shows the outward force over the expansion range from about 2mm to about 6 mm. It can be seen that the slope of line B3 is much greater than the slope measured in the plaque tack at all points along its range of 2mm to 6 mm. The net effect of this higher slope is that SMART stents are much more sensitive to changes in the size of the inner diameter of the vessel in which the stent is deployed.

As can be seen in fig. 6A, in some embodiments of the plaque tack, the low slope of the force curve is substantially flat over a range of outer diameter expansion of about 3mm or greater. In other embodiments, the low slope of the force curve may have a change in force of less than 1N over a 2.5mm outer diameter expansion range. Factors that contribute to the nail's ability to have a wide range of radial force variations less than 1N include the midline anchors discussed above, the double-amplitude struts, and the varying strut thicknesses.

The staples are radially self-expanding, passing through a range of at least about 2mm, generally at least about 3mm, and typically at least about 4mm or 5mm, while exhibiting a radial expansion force of no more than about 5N at any point throughout the range. In some embodiments, the maximum radial expansion force for the entire expansion range is no more than about 4N, and preferably no more than about 3N. In one embodiment, the staple is expandable over a range of at least about 3mm (e.g., from about 3mm to at least about 6mm) and the radial expansion force is less than about 3 over the entire range. Generally, the expansion force will vary by no more than about 3N, and preferably no more than about 2N, throughout the expansion range. In one embodiment, the expansion force decreases from no more than about 2N at a diameter of 3mm to no more than about 1N at a diameter of 6 mm. Generally, the difference between the radial force of compression and the radial expansion force at any given diameter throughout the expansion range is no more than about 4N, generally no more than about 3N, preferably no more than about 2N, and in one embodiment no more than about 1N. In one implementation, the staple is expandable over a range including 3mm up to about 6.5mm, and the difference between the compression and expansion forces at each point along the compression/expansion range varies by no more than about 2N, preferably no more than about 1N.

Generally, it is preferred that the outward force of the plaque tack 10' be as low as possible while providing sufficient force to keep plaque through a wide range of lumen diameters against the lumen wall. When the force is elevated (e.g., 2 to 3 times), an adequate holding force may have adverse side effects. These may include stimulating cells of the vessel wall in contact with the device, which may lead to restenosis. While very low force devices are preferred for general treatment, higher force devices may be useful in cases where loose plaque is found in calcified lesions.

One advantage of having a slow change in force as the device is expanded is the ability to predict that the vessel is independent of the energy experienced by the lumen diameter. Another value would be a reduction in the necessary inventory for the hospital. For example, it has been found that the two-part size of the peg 10' shown in fig. 5A-5C can be used for plaque peg treatment in blood vessels located throughout the leg from the hip to the ankle. This is believed to be due in large part to the slope of the nail 10' being less than-0.3N/mm.

c. Plaque tack design parameters

One purpose of the plaque tack described herein (as distinguished from conventional stents) is to minimize the amount of implanted external material while still performing focal treatment of the vascular condition so that minimal vessel wall reactions and adverse post-treatment restenosis occur. The plaque tack is designed to have substantially less metal coverage and/or contact with the vessel surface, thereby provoking less acute and chronic inflammation (see figure 6B). Reducing the contact area of the implant material against the vessel wall is associated with a lower incidence of intimal hyperplasia and better long-term patency. The greatly reduced length of the axial distance along the vessel allows for more targeted treatment, in connection with a smaller outer body coverage of the vessel surface, avoiding covering parts of the surface that do not need to be covered, and in connection with both early and late improving the patency of the vessel reconstruction.

The plaque tack may be deployed only where needed to tack plaque that has been destroyed by balloon angioplasty or other mechanisms. The plaque tack may be placed locally and selectively (e.g., not extending to normal or less diseased arterial segments), rather than covering the entire area of treatment (see fig. 6B). This allows the vessel to retain its natural flexibility because there is minimal to no backbone when small profile (smallprofile) staples are used locally or even when multiple staples are spaced apart from each other over the treatment area. Further reductions in pressure spectrum can also be obtained by using "point contacts" to obtain higher pressures at the lesion and to raise adjacent strut segments away from the vessel wall, thereby reducing the overall loading of outward pressure elsewhere on the staple strut structure.

One parameter of the design of plaque staples is that the ratio of the axial length of the staple to the expanded diameter (L/D) is no more than about 2.0, often no more than about 1.5, and in some implementations no more than about 1. In one embodiment, the L/D ratio of the staples is about 0.8. That is, the length of the staple along the axis of the vessel is about equal to or less than the expanded diameter of the staple. Thus, the preferred plaque tack is shaped like a circular ring or band, while the typical stent is shaped like an elongated tube. Thus, the low profile staple may be used locally to target a damaged area of the vessel surface with minimal foreign material coverage or contact. Experiments have shown that plaque pegs having an axial length/diameter ratio ≦ 1 cause little biological reaction or subsequent narrowing of the vessel compared to conventional stents, which have an axial length greater than the diameter and are typically much larger. Experiments have shown that device L/D ≦ 1 results in a reduction in the scaffold (much less than that of a typical stent) and causes less arterial wall response. For application at small exfoliation sites after balloon angioplasty, a minimum footprint plaque tack, such as a single, thin ring tack with an L/D ratio in the range of 1/10 to 1/100, may be used.

Studies with stents have shown that the axial length of the stent is related to the propensity for occlusion in multiple vascular regions. The longer the axial length of the stent placed, the higher the likelihood of reconstruction failure. The axial length of the stent when placed in the superficial femoral artery is also directly related to the tendency and frequency of the stent to fracture. The medical literature indicates that the superficial femoral artery behaves like a rubber band, and it is likely that changes in the natural elongation and contraction of the superficial femoral artery play an important role in the failure model of the superficial femoral artery stent. Conversely, low profile plaque staples can only be implanted in localized areas where the use of plaque staples is required, thereby enabling the vessel to retain its natural flexibility to move and bend even after the surface has undergone stapling. The implanted plurality of staples may be separated by regions without metal struts, leaving the artery free to bend more naturally.

Even when multiple staples are used in a spaced apart configuration, the outward radial pressure applied to the vessel wall can be significantly reduced by a low profile staple design. To minimize this outward force, while still providing the desired retention of the exfoliation against the arterial wall, a series of anchor barbs or focal elevating elements may be used. The presence of these features, which apply focal pressure to the artery wall, allows the remainder of the spike to apply minimal outward force to the artery wall. The point at which pressure is applied can be very local and this is where most of the force is applied. The focal nature of the application of force by the nail also minimizes the structural impact of the device. Evenly distributed anchoring elements or focal elevating elements can provide radial energy distribution that maximizes the tendency to form a circular lumen.

Another important parameter for the design of plaque spikes is the ratio of the vessel coverage area (C) to the total vessel surface area (TVS). In one definition, the value C is the length of the prosthesis (e.g., stent or tack) multiplied by the average circumference of the vessel in which the prosthesis is placed, and the value TVS may be the length of the lesion or area in need of treatment multiplied by the same nominal circumference. This can also be simplified to the ratio of the total length of the prosthesis divided by the length of the lesion in the vessel when expanded to the nominal circumference. These concepts may be applied to one stapling device or when several spaced apart stapling devices are placed across the length of a vessel treatment area. When multiple stents or staples are used, the simplified ratio may be the total non-overlapping length divided by the length of the lesion or may be the sum of the length of the prosthesis divided by the sum of one or more lengths of one or more lesions. For plaque pegs, the C/TVS ratio is in the range of about 60% or less, while for stents it may be 100% or more (if applied to overlapping treatment sites).

For focal lesions, the length of the vessel for conventional treatment is X +10mm to 20mm, where X is the length of the lesion and the added length is the length of the adjacent normal or less diseased artery proximal or distal to the lesion. In a conventional stent, the entire treated length of vessel will be covered by the stent. For example, in the case of a 2cm lesion, the length of vessel treated will be 3cm to 4cm (a single stent of this length is typically selected) so that the C/TVS is 150% to 200%. Conversely, with the placement of the staples, an X of about 1/2 would be covered and none of the adjacent normal or less diseased arteries would be treated. For example, in a 2cm lesion, about 1cm will be covered so that the C/TVS ratio is about 60% or less. One advantageous aspect of this innovative approach is that the placement of the band is only in the anatomical region where the vessel peg is needed.

As previously described, in some embodiments, the stapling apparatus 10' is formed by a loop or mesh strip 12 connected by longitudinal bridging members 14 (fig. 5A). In the figures, the staple 10' is shown compressed for delivery in a blood vessel. When expanded, the diameter of the stapling instrument may be approximately equal to the axial length of the stapling instrument.

FIG. 6B illustrates the use of multiple stapling devices spaced apart over the length of the vessel at the treatment site as compared to a typical stent, preferably the spacing between the stapling devices is at least the axial length of the stapling devices, it should be noted that the spacing between adjacent stapling devices leaves an untreated vessel region²) Is the same for a series of spaced apart stapling devices, C is equal to 6 × 0.6cm × 0.6 pi, or 6.78cm²And TVS is 12.44cm²Therefore, the C/TVS ratio is equal to 54.5%.

When two or more stents need to be employed over an extended length of treatment site, it has become a common practice to overlap adjacent stents to prevent kinking between the stents. Due to the added metal lattice, the overlapped regions become highly rigid and non-conformal. This non-compliant doubly rigid region also limits the natural arterial flexibility and increases the tendency for restenosis. Stent fractures occur more frequently in the superficial femoral artery where such bending occurs at high frequencies and are common when multiple stents are deployed and overlapped. Stent rupture is associated with a higher risk of in-stent restenosis and reocclusion. In contrast, the plaque pegs are designed to be applied in a local area and not to overlap. The optimum spacing is the minimum of the axial length separating the staples by 1 staple. This allows the artery to maintain its flexibility and only half or less of the treated length of the artery will be covered with metal. It should be noted that in the event of restenosis, the stent is still allowed to remain open after placement of the staples for the entire treatment length that overlaps the stent. This is because the repeating pattern of areas where no staples are placed provides a cushioning area and bends the artery.

The literature in the industry has noted that important factors in Stent design are the ratio of relative metal surface Area (RMS) and the number of longitudinal segments in the device structure, for example, as presented by Mosseri M, Rozenman Y, Mereita A, Hasin Y, Gotsman M, "New Indicator for Stem Covering Area," catalysis and coronary diagnostics, 1998, Vol. 445, pp. 188-. More particularly, for a given metal surface area, a higher number of longitudinal segments (with each longitudinal segment being thinner) can reduce the size of the gap between adjacent segments, reducing the tendency for sag. As adapted from the RMS measurement, the formula for the Effective Metal Interface (EMI) can be used to compare an embodiment of a nail device with a longitudinal bridging member to a generic stent, as follows:

where x is the number of segments of metal, l is the individual metal segment length, w is the individual metal segment width, C is the vessel coverage area (luminal surface) under the device, and n is the number of bridging members connected longitudinally between circumferentially oriented segments. The sum appearing in the denominator can be interpreted as the total metal surface area. The EMI of the embodiment of the nail device with longitudinal bridging members is ≦ 10, while the EMI of a typical bracket would be several times greater. This low EMI is due to the nature of the staple design with a small footprint and minimal longitudinal bridges, whereas stents typically have a larger footprint and are several times larger.

To is coming toFurther reduction of EMI by inclusion of lift-off-bump features (e.g., anchors, barbs, or focal lift elements), improved EMI may be obtained for provided nail effective metal interfaces with floating elements_F(see FIG. 9). EMI (electro-magnetic interference)_FCan be defined as:

wherein all variables are the same as in the EMI equation and added_FIs the length of the single metal segment that is not in contact with (floats off) the artery, and W_FIs the width of the same section. If no floating section is present, n_F0 and l_Fw_F0 and thus EMI_F＝EMI。

Comprising floating metal sections (floating length l)_FWidth of float w_FAnd the number n of floating bridges_F) Further reduction of EMI, which is mathematically captured as EMI_FThe sum of negative variables (negative variables) in the formula.

The presence of raised mass features (e.g., anchors, barbs, or lesion-elevating elements) on the plaque tack minimizes the pressure of the entire structure on the vessel wall by transferring the area-outward force to the lesion pressure point, thereby applying higher pressure at the lesion. The presence of the raised mass feature that applies focal pressure to the artery wall allows the remainder of the staple to apply minimal outward force to the artery wall. Regardless of where the lift block feature is placed, the outward radial energy is maximized in that region, producing a slight outward bowing of the artery wall. Outward bowing can be used for angioplasty or molding. For example, 5 or more evenly distributed focal points may be used to form a circular lumen. The circular lumen provides additional benefits from the standpoint of vessel wall interaction, independent of vascular injury.

In any of the embodiments discussed herein, the plaque tack device can be made of nitinol, silicon composite (with or without an inert coating), polyglycolic acid, or some other superelastic material, as well as stainless steel, tantalum, cobalt-chromium alloys, bioabsorbable or bioresorbable materials (including bioabsorbable/bioresorbable metals), or polymers. The material strips can be produced from strip-shaped, round or rectangular wires or material sheets by the following processes: photolithography, laser or water cutting, mechanical removal of the final shape or chemical etching, or using bottom-up fabrication (e.g., chemical vapor deposition processes), or using spray forming, hot stamping, or using electroplated or electroless plating. The plaque tack device can be made of metal, plastic, ceramic, or composite materials.

The plaque tack device is designed to be inherently self-aligning, i.e., the mechanical installation of the plaque tack device can accommodate small misalignments. The staples themselves are aligned with the longitudinal axis of the artery by reducing the stress on the strut members while grasping the artery wall at the designed center. Design features that provide stress buffering and provide uniform distribution of open struts include: the narrow spacing of the anchors, struts of non-uniform thickness, anchor head are angled to reduce forward springing of the device during delivery. As described above, the circumferentially oriented anchors at each bridging member provide gripping force and embedding features with the catheter tip when placed against the artery wall. These design features are used to advantageously place the staple at a specific location within the diseased vessel.

Improvement of focus elevating elements

Figures 7A-7D illustrate a plaque tack 10 "similar to figures 5A-5C except as discussed below. In particular, the plaque tack 10 "comprises the following features: the features or amount of interaction between the plaque tack 10 "and the vasculature is reduced by lifting a portion of the plaque tack 10" away from the vessel wall when deployed.

In particular, the high outer apex 24' formed by struts 26 and 27 curves or turns upward or radially outward to form a Focal Elevating Element (FEE) 32. Fig. 8 shows a schematic diagram of the FEE 32. In this embodiment, the high outer apex 24' is curved to form an angle with the struts 26 and 27. In this manner, the FEE 32 may help minimize the amount of the plaque tack 10 "in contact with plaque and/or vessel walls, while also limiting the force to several points to more firmly place the plaque tack 10". These and additional benefits are described in more detail below.

An plaque tack device can be provided having a focal elevating element on the annular periphery of the device. The focal elevating elements, unlike typical anchors and barbs, have larger plaque or arterial wall penetration to anchor or stabilize the staples in the vessel.

The focal elevating elements may or may not penetrate but may still provide regional elevation of the struts and are preferably located at the apex of the struts or periodically along (e.g., perpendicular to) the length of the struts. For both the anchoring elements and the focal elevating elements, the size of the interface between the peg and the artery wall is preferably equal to or shorter than the width of the strut in at least one direction. The focal elevating elements may resemble anchors but do not penetrate tissue or penetrate tissue only slightly, thereby minimizing the amount of material surface area in contact with plaque, and providing a set of relief sections for outward pressure of the stapling device adjacent the focal elevating elements, thereby minimizing friction at the vessel wall.

The focal elevating elements may be formed and configured on the annular periphery of the stapling instrument in a manner similar to that described for previous embodiments of stapling instruments, and may contain raised contact portions other than anchors or sharp points. The contact section may provide improved stapling characteristics in that the contact section increases the contact force at the contact section by compressing the plaque at the contact area and reducing the outward force at the portion adjacent to the focal elevating element. This provides regional pressure relief in some sections and increased contact pressure at the bump or cusp, collectively providing a reduction in cellular response of the wound and vessel wall.

Because the stapling device is held in place by its own pressure exerted on the vessel surface, the stapling device is susceptible to abrasion, including slight movement between the device and the vessel surface. An artery moves whenever an organ moves (e.g., a leg is walking). It can be concluded that when the artery moves, the working device, which is located in the artery, also moves, but it is not necessarily required that each contact point moves together synchronously. Artery-device friction promotes cellular responses and device failure whenever there is even a small mismatch in motion between the artery and the device. It has been concluded from experiments that this abrasion may stimulate the endothelium to elicit an inflammatory response. In some embodiments, strategic placement of Focal Elevating Elements (FEE) is intended to reduce the frictional load (believed to be the source of inflammation, cell proliferation, and the healing response leading to restenosis) across the entire area of the area remaining open.

As an example, a blood vessel such as the periodically shortened and elongated popliteal artery (popliteal), for example, is considered to have a cellular or tissue structure that is elongated and compressed in a direction parallel to the axis of the vessel. The natural behavior of this cell or tissue structure includes a significant amount of local motion along the axial direction. If the implant to be placed in such a vessel is designed to be in contact with the vessel wall in a direction transverse to the axial direction, the natural behavior of these tissues or cells will be severely disturbed. For example, the tissue will be restricted and the natural motion will be greatly reduced. In addition, abrasion can occur along the edges of the lateral contact structure, resulting in abrasion and/or abrasion of the tissue and corresponding inflammation. In contrast, FEE reduces disruption to the natural behavior of tissues or cells. If incorporated into a staple device or other prosthesis, the FEE may concentrate the contacts in areas spaced apart in a direction transverse to the primary direction of motion (e.g., the axial direction in the case of the popliteal artery or similar vessel). The interaction of compressed and elongated tissue or cells with the structure of the implant is greatly reduced between these areas of concentrated contact corresponding to the FEE. In this region between the two, the motion between the compressed and elongated tissue or cells may approximate the motion of the tissue or cells prior to implantation of the prosthesis. The elevated section created by the FEE limits the histological response of the tissue and also limits fatigue of the device by contact between the limiting device and the tissue.

Regardless of the number of FEEs and the total amount of contact, the stapling device smoothes the lumen wall and allows for more natural vessel motion. The greatest value of FEE is where the amount of interaction between moving, elongated or compressed tissues or cells that can cause abrasion or abrasion to such tissues or cells can be reduced. This is a highly localized motion or "micromotion" that increases the cellular response of the blood vessel surface to the external device.

Focal elevating elements are designed to reduce the Effective Metal Interface (EMI) by minimizing the overall material contact with the vessel surface. The Focal Elevating Element (FEE) is preferably configured as a narrow, elevated feature having sufficient height to elevate adjacent strut sections of the staple device out of contact with the arterial wall, thereby reducing the surface area of the foreign material in contact with the arterial wall. Reducing contact loads is of particular value when the strut members connect circumferential rings or circumferentially oriented strut bands. The portions of the stent in contact with the vessel wall that are oriented against the natural texture of the cell may create micro-friction as they move or rub against the vessel wall. By reducing the contact area of the foreign material against the vessel wall, the tendency to create microabrader contact is reduced.

Referring to fig. 9, a schematic diagram illustrates some design assumptions for using a focal elevating element on a plaque tack device. In the figure, h refers to the height of the lesion lift elements protruding from the vessel (note: the depth of penetration of the lesion lift elements, i.e. the depth of anchoring to the artery or plaque mass, is not included in the calculation), w refers to the width of the lesion lift elements (at their base) and l_FRefers to the surface of the adjacent strut (mathematically reduced to a straight line) lifted off the artery wall. Struts adjacent to the lesion promoting elements may be made of shape memory material or designed to provide compression waves that compensate for lumen diameter changes. Strut forces adjacent the focal elevating elements create outward bowing of the struts, which is caused by the force of the struts tending to expand until the struts contact the vessel wall. l_ARefers to the passage through the focusThe length of the arterial wall that the lift element does not contact any adjacent strut structure.

One or more of the features labeled in fig. 9 may be altered to provide advantageous FEE performance. For example, h may vary depending on the size of the delivery catheter, e.g., 4Fr provides h up to 150 um. In certain embodiments, the h for a peg with a FEE configured for delivery in a 4Fr catheter may be about 100um or less. An exemplary embodiment that can be deployed using a 4Fr delivery system has more than one FEE with h of about 75 um. For example, the h of a larger staple with a FEE configured for delivery in a 6Fr catheter may be up to about 300um and in some cases 225um or less. An exemplary embodiment that can be deployed using a 6Fr delivery system has more than one FEE with a h of about 200 um. For example, a larger nail configured to have a FEE delivered via an 8Fr catheter may have a h up to 950um, while in certain embodiments, a FEE of up to 500um may be provided. An exemplary embodiment that can be deployed using an 8Fr delivery system has more than one FEE with a h of about 400 um.

Any of the foregoing dimensions of h may be combined with various dimensions of W of the FEE. The W dimension is typically the width of the strut but may be only 50% of the strut width and may be between about 50% and about 100% of the width of the strut at the FEE location. I is_fAnd I_aIs a function of W, the radial force of the system, the profile of the lumen, and the delivery device, e.g., if a balloon is used to press the device into an artery, I_fAnd I_aAnd (4) changing. If only W (inelastic system) is seen, then I_aMay be approximately equal to the length of the strut. If the outward force (both from the elasticity of the metal and balloon assist) increases, then I_aDecreases, close to 0. However, in various embodiments, I_aAt least about 20 um.

The focal elevating element may be formed as a cylindrical, rectangular, linear, spherical, conical, teardrop, pyramidal, or angled element on the annular periphery of the tack device. The lesion promoting elements may be formed by: bending or stamping a portion of the pin structure, adding processes (e.g., by welding or annealing on the outer peripheral surface), trimming processes (e.g., by grinding or etching away surrounding material so that the block elements are taller than the surrounding surface), or modifying a small portion of the peripheral surface to be taller than the surrounding surface before or after the sheet or tube is cut. For example, one way to modify a small portion of a mesh tack structure is by knotting, twisting, bending or weaving a small portion of a wire mesh to create elements that protrude from the mesh side of the tack device that is attached to the artery wall.

A correctly oriented and symmetrically positioned lesion lift element may provide a focal point for the expansive force. As the device applies an outward force and the artery applies an inward force, the lesion lifting element may be positioned in a strategic placement position that reduces outward pressure of the strut section adjacent the lesion lifting element.

Both anchors and lesion lift elements may provide strategic advantages, including: reducing the pressure load across the staple struts by reducing the contact area and transferring outward forces to the anchoring elements and focal elevating elements, minimizing surface contact provides a reduction in the tendency of frictional loads driven by micro-motion between the arterial wall and the staple struts, and stabilizing the anchoring of the staple at a portion of the characteristic height of the anchoring elements or focal elevating elements penetrating the vessel wall.

Because the tack device is held in place by its own outward pressure exerted on the plaque and vessel surface, it is susceptible to abrasion (i.e., slight movement between the device and the vessel surface). Figure 10 shows the forces acting between the focal elevating element and the artery wall. FT is the circumferential force applied by the staple device against the arterial wall force FA. F_FEEIs an additional circumferential force generated at the focal elevating element by design and material selection, and F_FIs the frictional force of the artery that is generated when the artery changes its direction or shape due to body force. Whenever a body part moves, the blood vessels also move slightly. The focal elevating elements may be strategically positioned to reduce body mass that may cause inflammation, cell proliferation, or cause restenosisLocal frictional loading of the reaction.

The number and location of focal elevating elements can affect the total relative metal surface area (RMS) as previously described. The focal elevating elements may be positioned along the length of the staple device surface so that a minimal amount of metallic surface area is in contact with the artery wall. Focal elevating elements of bridges placed between circumferential strut rings or at the apex of strut sections of the stapling device can provide most of the arterial lesion mitigation. When focal elevating elements are placed only at the apex and bridge, the RMS of the strut members making up the concentric rings varies little, while the RMS of the bridge decreases significantly, mitigating relative motion of the circumferentially oriented strut rings due to the narrow length.

Fig. 11 and 12 illustrate the use of focal elevating elements of the type described above in accordance with fig. 5A-5C on a stapling device having two or more concentric ring portions connected therebetween by a bridge. Fig. 11 shows a unit with two adjacent ring portions 290a and 290b connected in between by a bridge 290d, the ring portions 290a and 290b having strut sections 290 c. Fig. 12 shows the ring portions expanded under the expansion force and the deployment of oppositely disposed focal elevating elements 290e on opposite ends of two adjacent ring portions 290a and 290 b. The inset of the figure shows a circular focal elevating element with a height that is raised from the surface of the post.

Fig. 13 and 14 show a unit of another variation of a focal elevating element formed on a stapling device having two or more concentric ring portions 300a, 300b connected therebetween by a bridge 300 d. In this unit variation, the focal elevating element 300e is formed by bending a portion of the strut (illustrated strut apex) out of the circumferential plane to different degrees of tilt, such as position "a", or position "b", to a 90 degree perpendicular orientation as shown at position "c".

An inherent property of using shape memory alloys for stapling devices is the ability to conform to the shape of the vessel wall. Because the lesion lifting elements may exert an expansion pressure on the vessel wall with minimal risk of damage, the lesion lifting elements may be designed to reshape the vessel wall into a desired shape. Fig. 15 shows focal elevating elements (fes) positioned in diametrically opposed locations and formed with extended heights to reshape the arterial wall into an elliptical cross-sectional shape that may better match the arterial cross-section (e.g., arterial branches) or expand the lumen more open in the region of the non-plaque.

Fig. 16 shows a side view of the fes spaced along the strut length with a small area lifted off the artery due to the height of the fes raising the adjacent stent length a short distance. The outward force created by the design or materials used allows only a small portion on either side of the FEE to lift off the vessel wall.

FIG. 17 shows a perspective view of a series of FEEs spaced along the length of a post section of a stapling device. FIG. 18 shows a detailed view of a cylindrical FEE located at the apex of a post segment of a stapling device. Fig. 19 shows a perspective view of a FEE formed as a pyramidal element at the apex of a strut section. Fig. 20 shows a perspective view of a FEE formed as a dome element at the apex of a strut section. Fig. 21 shows a perspective view of a FEE formed by bending the apex of the strut section upward. Fig. 22 shows a perspective view of a FEE formed by twisting a strut section (made of wire).

Methods and devices for delivering plaque tacks and forming intravascular structures in situ

Some of the various delivery methods and devices that may be used to deploy the plaque tack are described below. For example, plaque tacks may be delivered into a blood vessel using intravascular insertion. The delivery devices for different embodiments of the plaque tack may be different or the same, and may have features specifically designed to deliver a particular tack. The plaque tack and installation process can be designed in a number of ways that share the following methods: the staples can be moved to a position in the vessel using the expansion force of the delivery mechanism (e.g., balloon expansion) and/or the expansion force of the compressible annular band, and then released, opened, or unstranded to an expanded state within the vessel.

Referring back to fig. 4-4D, the delivery device or catheter 11 is shown with the outer sheath 13 in a pre-delivery state. A plurality of plaque staples 10 can be compressed for loading onto the surface of a delivery device 11. The outer sheath 13 may then be advanced to cover the plaque tack 10 ready for delivery. In some embodiments, the plaque tack 10 is rapidly frozen in its compressed state to facilitate loading onto a delivery device. The staples may extend in an array 10x over a given length of the delivery device.

As can be seen, the plaque tack 10 can be positioned in the vasculature of a patient at a treatment site by a delivery device 11. The outer sheath 13 may be withdrawn or retracted to expose and release the plaque tack 10. The staples 10 may then be expanded in any suitable manner, such as by being configured to self-expand or balloon expand as discussed herein.

Turning now to fig. 23-31B, a method of delivery of one or more staples 10 "will be described. As already mentioned, an angioplasty procedure or other type of surgery may be performed in the blood vessel 7. Angioplasty may be performed on a diseased or occluded portion of the blood vessel 7. A diseased vessel may first be accessed using a cannula and the guidewire 40 advanced through the cannula to the desired location. As shown in fig. 23, an angioplasty balloon catheter carrying a balloon 42 is advanced over a guidewire 40 into the blood vessel 7 at a location containing obstructions formed by plaque. The balloon 42 is inflated at the desired location to compress the plaque and widen the blood vessel 7 (fig. 24). The balloon 42 may then be deflated and removed.

When the blood vessel 7 is widened, exfoliation 44 of the plaque may be caused by angioplasty (fig. 25). Angiography can be performed after angioplasty to visualize the vessel in which the angioplasty is performed and to determine if there is evidence of post-angioplasty peeling or surface irregularities. The plaque tack or staple 10 "can then be used to secure the plaque peel 44 or other surface irregularities to the luminal wall 7 as desired.

A delivery catheter 11' pre-loaded with one or more staples 10 "may be advanced through the cannula over the guidewire 40 to the treatment site (fig. 26). In some embodiments, new or separate guidewires and cannulae may be used. A distal-most marker on the catheter or on the distal-most plaque tack may be visually positioned at the treatment location. The outer sheath 13' may be withdrawn, exposing a portion of the plaque tack 10 ". As discussed, the outer sheath 13' may be withdrawn until a set point, and then the position of the intravascular catheter may be adjusted, if necessary, to ensure accurate placement of the plaque tack 10 "(fig. 27). For example, the set point may be just before any staples are uncovered, a portion or all of the uncovered loop, the uncovered loop and anchors, and so forth.

The nail 10 "can then be released at the desired location in the lumen. As previously discussed, simultaneous placement may result when some embodiments of the plaque tack 10 "are released. Additional plaque staples 10 "can then be placed distal to proximal within the treatment section of the vessel as desired (fig. 28).

In some embodiments, the precise placement of the plaque tack 10 "can be set when positioning the catheter based on the location of the marker within the vessel. Once positioned, one or more tacks may then be deployed while maintaining the catheter in place and slowly removing the sheath.

Upon placement of the second staple 10 ", the endovascular structure 11 is formed in situ. In situ placement may be in any suitable vessel, such as in any peripheral artery. The structure need not be limited to only two spikes 10 ". In fact, a plurality of at least three intravascular staples 10 "(or any other staples herein) may be provided in the in situ formed intravascular structure. In one embodiment, each staple of the plurality of staples is no more than about 8mm in length, for example, about 6mm in an uncompressed state. In one configuration, at least one staple (e.g., each staple) is spaced at least about 4mm, or between about 4mm and 8mm, or between about 6mm and 8mm from an adjacent staple. While the staples in certain embodiments have a length of 8mm or less, other embodiments may be longer, for example up to about 15mm long. In addition, adjacent spikes 10' are positioned as close to 2mm apart, particularly in vessels that are not prone to bending or other movement. In one embodiment, each staple has a relatively low radial force, e.g., a radial expansion force of no more than about 4N, and in some cases about 1N or less. In some embodiments, the staples may be configured to have a radial force as little as 0.25N. In the various delivery devices described herein, the spacing between implanted staples may be controlled to maintain a set or minimum distance between each staple. It can be seen that the delivery device and/or the staples can include features that help maintain a desired distance between the staples. Maintaining proper staple spacing can help ensure that the staples are distributed over the desired length without touching each other or bunching up in a certain area of the vessel being treated. This helps to prevent kinking of the vessel in which the staples are disposed.

While three peg structures formed in situ may be suitable for certain indications, an intravascular structure having at least 5 intravascular pegs may be beneficial for treating loose plaque, vascular flaps, sloughs, or other diseases of significantly longer (non-focal) length. For example, while most exfoliation are focal (e.g., axially short), a series of exfoliation may be considered and treated as a longer disease.

In some cases, shorter axial length staples may be used to treat even more spaced apart locations. For example, a plurality of staples, each having a length of no more than about 7mm, may be placed within a vessel to treat a tackable disease. At least some of the staples (e.g., each staple) may be spaced apart from adjacent staples by at least about 5 mm. In some cases, it may be preferable to provide a gap ranging from about 6mm to about 10mm between adjacent staples.

Optionally, once the plaque tack 10 "is in place, the angioplasty balloon can be returned to the treatment site and inflated to expand the plaque tack 10" to the desired expanded state. Figure 29 shows the plaque tack 10 "in its final implanted state.

With reference to fig. 29, 30A and 30B, it can be seen how the focal elevating elements 32 penetrate the plaque in the vessel wall and also minimize the contact area of the plaque tack 10 "with the vessel wall. Similarly, fig. 29, 31A and 31B illustrate the penetration of anchor 20. It can also be seen that the location of the anchors 20 on the bridge 14 allows the anchors to tangentially protrude from the circular shape formed by the plaque tack 10 ". This advantageously allows the anchoring elements 20 to engage the plaque or vessel wall while also minimizing the total amount of contact by the plaque tack 10 ", similar to the focal elevating elements 32.

A. Other systems and methods for delivering plaque staples

Fig. 32A-48D illustrate a system for delivering a vascular prosthesis, such as any of the intravascular staples or plaques described above. Fig. 32A shows a system 100 for controlling the delivery of self-expanding staples. Other systems discussed below may be used to further enhance the deployed position of the staples and the deployment of staples that are at least partially expanded by an outward radial force.

The system 100 includes a catheter assembly 104 and a fixation device 108 coupled to the catheter assembly 104. The fixture 108 may have a smaller configuration to facilitate hand-holding, but in some embodiments the fixture is secured to a larger object or otherwise configured to be stationary. The catheter assembly 104 may be received within the fixture 108 and held in place therein to limit or preclude unwanted relative movement between the fixture and at least one component of the catheter assembly 104. For example, the fixation device 108 may include one or more caps 112 that may be configured to retain a portion of the catheter assembly 104. Fig. 32A shows that in one embodiment, the fixation device 108 includes a proximal cap 112A and a distal cap 112B, which will be discussed in more detail below. The covers 112A, 112B may be removable to allow the clinician to place the catheter assembly 104 into the fixture 108 or may be pre-connected to the catheter assembly. The features of the fixation device 108 may be combined with or expanded by those features of the drawings of fig. 46-48D, fig. 46-48D depicting further details of the proximally disposed deployment system.

The catheter assembly 104 includes an elongate body 132, a sheath 136, and a plurality of intravascular tacks 140. Although one staple 140 is shown in fig. 32B and 33B, a plurality of additional staples may be disposed within the catheter assembly 104, as discussed below in connection with fig. 36A.

Figures 36-36A illustrate that elongate body 132 has a proximal end 152, a distal end 156, and a plurality of delivery platforms 160 disposed adjacent the distal end. Each delivery platform 160 includes a groove 164 (fig. 33B and 36A) extending distally of an annular marker band 168. The annular marker band 168 has a larger outer diameter than the groove 164. In some embodiments, the groove 164 may be defined as a smaller diameter region adjacent to or between one or both of the annular marker bands 168 and/or another feature on the elongate body 132. The platform 160 is shown schematically in fig. 32A-33B, and in more detail in fig. 36A. In embodiments having a plurality of staples 140, a plurality of corresponding delivery platforms 160 are provided. Any number of staples and platforms may be provided, for example, four staples and platforms, two or more staples and platforms, 3 to 20 staples and platforms, or other configurations. Each delivery platform 160 may contain at least one marker band 168. For example, proximal marker band 168A and distal marker band 168B may be provided so that the ends of platform 160 are visible using standard visualization techniques. In the illustrated embodiment, the proximal marker band 168A of the first platform 160 is also the distal marker band of the platform positioned immediately distally.

The annular marker band 168 may take any suitable form, for example, including one or more of tantalum, iridium, and platinum materials. In one particular configuration (see fig. 36A), the proximal-most marker band 168A comprises tantalum, while the distal marker band 168B comprises one or more of platinum and iridium. The use of different materials that are radiopaque may be based on cost or preference for higher visibility and/or thinner construction. Platinum/iridium provides greater radiopacity than tantalum, making the distal marker band thinner or more visible than the tantalum band.

The ability to increase radiopacity to enable the physician to visualize the delivery device and staples under fluoroscopy may be provided in various ways. One example is to include thicker regions of material (wider circumferentially or thicker radially).

In addition, the annular marker band 168 has a radial height, which is the radial distance from the base of the groove 164 to the top of the band. The radial distance may vary, but is preferably just high enough to prevent staples 140 from being pinched between elongate body 132 and sheath 136 at annular marker band 168. In certain embodiments, the radial distance is approximately equal to at least the thickness of the staples 140 disposed in the catheter assembly 104.

In another embodiment, the delivery platform 160 is disposed distal to the proximal marker bands 168A', where the marker bands are frustoconical such that the radius of the proximal end of each marker band is nearly equal to the radius of the sheath 136, while the radius of the marker bands at the distal end is a reduced radius, as shown in fig. 36B. In some embodiments, the reduced radius may be the original radius of the elongate body 132 or the groove 164 described above. In other words, the marker band proximal end is angled upward toward the next, very proximal, staple. This creates a wall 170 at the proximal end of the marker band 168A'. The distal end of the staple abuts the wall and in this manner, the marker band can help to properly place the staple. Further, the ramped surface may be used to facilitate smooth withdrawal of the sheath from the elongate body when delivering the staples. For example, the ramped surface may limit the ability of the spike (pre-deployment) to hang over the marker band when the sheath is retracted. In some cases, the staple may have a strut member that is not completely opposite the wall, and tilting the marker band may limit the ability of the marker band to grasp this protruding strut member as the sheath is withdrawn. In this configuration, the distal portion of the staple will rest on the delivery platform just proximal to the beveled edge of the proximal marker band in the delivery system 100, as opposed to just abutting the wall of the untilted marker band.

In a different embodiment, the marker bands 168A "may be frustoconical in opposite directions with the radius being greatest near the distal end and the proximal end sloping downward, as shown in fig. 36C. In this embodiment, marker band 168A "has a wall 171 at the distal end. The inclined surface may be used to facilitate smooth withdrawal of the elongate member after the staple is delivered. For example, the sloped surface may limit the ability of the staples (after deployment) to hang 168A "on the marker band when the elongate member is retracted from the vessel wall. In variations, the delivery platform is frustoconical in one or more directions.

The marker bands may be frustoconical in one or more directions. The frusto-conical section of the marker band may be formed by glue securing the marker band on the elongate member. The glue may form a rounded corner between the marker band and the elongate member. The rounded corners may have a concave, substantially planar, or convex outer surface. In some embodiments, the marker bands may have rounded corners with different outer surfaces on either side. For example, the marker band may have a concave rounded corner at the distal end and a substantially planar outer surface at the proximal end or a rounded corner that is less concave than the outer surface of the rounded corner at the distal end.

In some variations, the staples 140 are fully self-expanding. In other variations, at least one of the delivery platforms 160 includes an expandable member to expand a staple disposed thereon. The expandable member may comprise a standard structure or specific design for balloon angioplasty, such as fig. 45. The staples 140 may also be deployed by a dedicated balloon coated with a drug to minimize restenosis, inflammation, or other side effects of treatment using plaque staples.

Elongate body 132 includes a distal tip 172 that is tapered to provide easy insertion, and a lumen 176 extending proximally from its distal tip to proximal end 152. As discussed with respect to fig. 4-4D and 23-31, the lumen 176 may be used with a guidewire to guide the distal end of the catheter assembly 104 to the treatment area. The proximal end 152 may take any suitable form, but is preferably configured to lockingly engage the fixation device 108. For example, fig. 36 shows that proximal end 152 may include a luer fitting hub (luer hub)178 having a flange that is receivable in a similarly shaped recess formed in fixation device 108. For example, a recess that at least partially matches the shape of the sleeve 178 may be formed between the base 110 and the cover 112A of the fixture 104. When the elongated body is received in the fixation device 104, the sleeve 178 is in this recess, positioned between the cover 112A and the base 110, and locked in place by the secure connection of the cover 112 to the base 110, preventing unwanted movement of the elongated body 132 relative to the sheath 136 and reducing or preventing movement relative to a fixed reference frame (e.g., the reference frame of the fixation device 104).

Sheath 136 has a proximal end 192 (fig. 32A, 33A), a distal end 198 (fig. 32B, 33B), and an elongate body 200 (fig. 33A) extending therebetween. Sheath 136 is movable relative to elongate body 132 from a first position to a second position. The sheath may be formed from a hypotube (such as a metal or plastic hypotube). The flexibility and stiffness of the sheath can be controlled by a number of characteristics such as the slope and frequency of the helical cut along the length of the hypotube.

Fig. 32A and 32B illustrate a first position or pre-deployment state of catheter assembly 104, wherein distal end 198 of sheath 136 is disposed distal of distal-most distal delivery platform 160. In fig. 32B, the most distal platform is occupied by a staple 140. Another platform is shown disposed proximate the proximal end of the occupied platform, the staples not shown for clarity, but which may be occupied by another staple. Other platforms and staples may be placed in closer proximity. Fig. 33A-33B illustrate a second position or deployed state of catheter assembly 104, wherein distal end 198 of sheath 136 is disposed proximally of a portion of at least one delivery platform 160, thereby releasing staples 140.

Sheath 136 may also include a bifurcated luer fitting (luer)204 having a main arm to accommodate elongate body 132 and side arm 206. A bifurcated luer fitting 204 may be provided at the proximal end of the sheath 136. Side arm 206 contains an irrigation port to vent air and increase lubricity in the space between the sheath and elongate body 132. A tuohy borst adaptor, hemostatic valve, or other sealing device 208 may be provided at the proximal end of bifurcated luer fitting 204 to receive and seal the distal end of elongate body 132 prior to application to a patient (e.g., during manufacture). tuohy borst adapter 208 may also provide a locking interface, such as a screw lock, to secure the relationship between sheath 136 and elongate body 132. As shown in fig. 32A, tuohy borst adapter 208 may lock to maintain the relationship between sheath 136 and elongate body 132 in a pre-deployed state. This may enable the surgeon to properly position the distal end without prematurely deploying the staples 140.

In some embodiments, a strain relief sleeve 212 is provided between the bifurcated luer fitting 204 and the elongate body 200 to make the connection more secure. A strain relief sleeve 212 may be located on the opposite end of the bifurcated luer fitting 204 from the tuohy borst adapter 208. The strain relief sleeve 212 may take any form such as being made of polyolefin or other similar material.

In one technique used, the distal end of the catheter assembly 104 is inserted into the patient and the proximal end is placed in the fixation device 108. Sheath 136 is in a distal position, e.g., forward with bifurcated luer 204 in fixation device 108 (fig. 32A and 32B). During surgery, as shown in fig. 33A and 33B, sheath 136 is gradually moved to a proximal position and the proximal portion of tuohyborst adapter 208 is brought into contact with the distal portion of cap 112A of fixation device 108. As sheath 136 moves proximally, the staples are deployed one at a time or all at once. After each deployment or set of deployments, the clinician may reposition the elongate body 132, or may perform one or more deployments without repositioning the elongate body 132. In some embodiments, a marking line (marking)534 may be located on the elongate body 132 to assist the clinician in the proper placement of one or more staples 140, as will be described in more detail below.

The fixation device 108 (fig. 32A and 33A) can facilitate placement of the plurality of staples 140 to the treatment area at spaced apart locations, as shown in fig. 29. For example, fixation device 108 reduces unintended relative movement between sheath 136 and elongate body 132. If securement device 108 is secured, the securement device helps limit movement of elongate body 132 due to internal friction that engages sheath 136 as bifurcated luer 204 is moved proximally. Thus, a more controlled deployment can be produced than if the physician were to directly hold both the proximal end of elongate body 132 and the proximal end of sheath 136. This helps to ensure that a minimum gap is provided between the distal ends of the proximal staples and the proximal ends of the distal staples in the treatment area. This gap can be seen in fig. 29, in which the deployment of two staples 10 "is shown. The gap advantageously minimizes the chance that the two staples will kink in a blood vessel or other ailment due to being too close together. The gap or spacing between the staples can be controlled in some embodiments from about 4mm to about 20 mm. In other embodiments, the spacing between the staples may be controlled from about 5mm to about 14 mm. In other embodiments, the spacing between the staples may be controlled from about 6mm to about 12mm, or from about 6mm to about 8 mm. As already mentioned, the tuohy borst adapter 208 may also lock the sheath 136 in place on the elongate body 132 to ensure that the catheter assembly 104 is in the pre-deployed state (fig. 32A and 32B), and also prevent unwanted movement. Applicants have found that the accuracy of a plurality of staples placed in this manner is within less than about 2mm and in some cases already less than about 1mm from the target delivery site.

Further, this configuration enables the placement of two or more staples without requiring the delivery platform 160 to move between deployments of the staples 140. Also, the delivery platform 160 may be positioned and held in place prior to deployment of the first staples 140. After deployment of the first staple 140, the delivery platform 160 may be maintained in a position and the sheath 136 may be retracted to expose and deploy the second staple 140, the third staple 140, or more staples.

The system 100 also provides the advantage of accurate placement of multiple vascular prostheses when the catheter assembly 104 is placed within a patient. In particular, the catheter assembly 104 need not be withdrawn after placement and replaced with another catheter or catheter system to perform further treatment. In this regard, the system 100 may be used with intravascular staples or staples as well as stents and other intravascular devices that are spaced apart in different treatment areas in a patient's body.

1. Minimizing motion using distal anchors

For some endovascular prostheses, accurate placement at a treatment site or region is important, for example, when the prosthesis is relatively short (e.g., the ratio of the axial length to the transverse width (e.g., diameter) of the prosthesis is 1 or less), or if placement occurs in a tortuous path (e.g., in an arterial curve). Stabilization at the proximal end (e.g., using fixation device 108) may provide reliable placement, but stabilization near the prosthesis may provide better accuracy in terms of axial position and minimizing the tilt of the device within the vessel. In this context, tilting includes any non-perpendicularity of the transverse axis projection (transverse aspect) of the device to the lumen in which the device is deployed. For nail 10', the transverse axis projection may be defined by a plane intersecting the high outer apex 24. A slope in a relatively short prosthesis may reduce its stability. For example, the inclination of the tack 10' may rotate the anchors 20 out of an optimal orientation for engagement with plaque, thereby reducing their effectiveness.

a. Minimizing motion using actively expandable distal anchors

Fig. 37A and 37B illustrate a delivery system 100A that is a variation of the delivery device 100, but the distal portion of the delivery system 100A is configured to stabilize the system in the vasculature for more precise placement of two or more staples. In particular, system 100A includes a stabilization device 250 disposed on an outer surface of the system, e.g., on an outer surface of elongate body 132A. The stabilization device 250 may be adapted to directly engage a body lumen. In some embodiments, the stabilization device 250 is adapted to engage the lumen at a plurality of locations disposed about the lumen, e.g., at discrete points of contact or at a continuous circumferential line or area. Such engagement facilitates minimizing movement of elongate body 132A relative to the body lumen when there is relative movement between sheath 136 and elongate body 132A. For example, the stabilization device 250 may maximize radial centering during movement of the sheath 136, which may facilitate control of the gap between adjacent staples deployed by the system 100A.

The stabilization device 250 can maximize radial centering during movement of the sheath 136 such that the center of the elongate body 132 at the distal-most delivery platform 160 is within about 50% of the radius of the vessel in which the platform resides, which can advantageously control the tilt of each staple deployed by the system 100A. In certain embodiments, the stabilization device 250 maintains the center of the elongate body 132 at the distal-most delivery platform 160 within about 40% of the radius of the vessel in which the delivery platform resides. In other embodiments, stabilization device 250 maintains the center of elongate body 132 at distal-most delivery platform 160 within about 30%, about 20%, or about 15% of the radius of the vessel in which the delivery platform resides. The radial offset may include a lateral displacement within the body lumen or an angle within the vessel segment. For example, the distal portion of the system 100A may have a different distance from the vessel wall along the length of its distal end due to twisting or bending of the vessel. The elongate body 200 of the sheath 136 forms an angle with the central longitudinal axis of the vessel when viewed from the side. Thus, one side of the elongate body 132A is closer to the vessel wall than the other and the distance varies with the length of the staple 140. This may result in one of the proximal or distal ends of the tack 140 engaging the vessel first, resulting in pinning into the vessel. The stabilization device 250 may bring the distal section of the system 100A closer to coaxial with the longitudinal axis of the vessel. For example, the stabilization device may be configured to maintain the longitudinal axis of elongate body 132A within 20 degrees of the longitudinal axis of the vessel for at least 4 delivery platforms. In some embodiments, stabilization device 250 may be configured to maintain the longitudinal axis of elongate body 132A at least 10mm within 10 degrees of the longitudinal axis of the vessel. In some embodiments, the stabilization device 250 may be configured to maintain the transverse axis projection of the staples 140 within 10 degrees of perpendicular to the longitudinal axis of the blood vessel.

The stabilization device 250 may be configured to reduce or minimize axial deflection. For example, the device 250 may reduce or minimize movement of one or more delivery platforms 160 along the lumen in which the platform vessel is disposed to enhance control of deployment. The stabilization device 250 may maintain the axial position of the distal outward-facing surface of the annular marker band 168 within about 15%, 20%, 30%, 40%, or 50% of the length of the delivery platform. The delivery platform length may be measured parallel to the longitudinal axis of elongate body 132 between the distal outward surface of proximal marker band 168A disposed proximally of the delivery platform and the proximal outward surface of distal marker band 168B disposed distally of the same delivery platform. In some applications, at least for the second or subsequent staples that are deployed, the axial offset is reduced or minimized, for example, to help maintain inter-staple spacing as discussed elsewhere herein. The stabilization device 250 may also be configured to reduce or minimize any offset in the position of the deployed first or subsequent staples when compared to the planned implant position. The planned implant position is an absolute position in the vessel where the clinician wishes to place the staples, which may be based on visualization techniques such as fluoroscopy or other surgical planning methods.

The stabilization device 250 may include an inflatable balloon 254 that may take any suitable shape. For example, the balloon 254 may be cylindrical or conical as shown in fig. 37A-37. One advantage of a conical balloon is that the inflation function provided by the tapered tip 172 can be performed by the leading edge of the tapered balloon, and thus these structures can be combined into some embodiments. Alternatively, if the anatomical structure is not cylindrical, a suitably shaped balloon (such as a conical balloon) may match the shape of the anatomical structure to provide better apposition.

In the illustrated embodiment, a cylindrical balloon 254 is disposed proximal to distal tip 172. A stabilization device 250 may be disposed between the distal end of elongate body 132A and at least one delivery platform 160. The balloon 254 is configured to minimize at least one of axial or radial offset of the at least one delivery platform 160 along or away from a longitudinal axis of a vessel in which the tack or other vascular prosthesis is deployed.

The balloon 254 may be inflated by any suitable method, such as by flowing an inflation medium from the proximal end of the elongate body through the lumen of the elongate body 132 to an inflation port of the balloon 254. The elongate body 132 of system 100A may be formed as a dual lumen extrusion, with one lumen for guiding the wire and the other lumen for inflating the balloon 254. The inflation lumen may be connected to a syringe or other source of positive pressure at the proximal end of elongate body 132 to deliver inflation media. Balloon 254 has a low profile configuration prior to inflation that enables it to rest on elongate body 132 without interfering with the delivery of the distal portion of system 100A. For example, the balloon 254 may be disposed within the sheath 136 (e.g., between an inner surface of the sheath 254 and the lumen 176) prior to inflation. In another embodiment, the balloon is disposed longitudinally between sheath 136 and tip 172. In such embodiments, it may be advantageous to have the balloon as a tip with the distal end tapered to allow navigation of the vessel, while the proximal end (e.g., radius) of the balloon is the same as the width of the sheath 136 to provide a smooth transition between the two to prevent any step at the interface between the balloon and the distal end of the sheath 136.

The use of the balloon 254 provides the clinician with the ability to initially place and expand the balloon at the distal end of the lesion site. The sheath 136 is then withdrawn to expose the one or more staples 140 for release at the predefined spaced locations after the balloon is anchored to the wall of the vessel. The locations of separation are predefined in that they correspond to a pre-established separation of staples on the delivery system 100A.

One advantage of the balloon 254 is the additional function of using the balloon for post-expansion of the staples after placement. In this case, after the staples are placed in the vessel, the balloon 254 may be repositioned within the deployed staples 140 and reinflated, the outward pressure used to expand the balloon engaging the staples to enhance the placement of the staples at the vessel wall.

Fig. 38 illustrates one of several embodiments in which a proximal control is provided to actuate a linkage (ligange) to move one or more distal components of the delivery system to create a radial expansion for secure engagement with a vessel wall anchor. In particular, the system 100B includes a stabilization device 250A configured to actively expand from a low-profile configuration to an expanded configuration. The low-profile configuration is a configuration suitable for advancement through the vasculature. The low profile configuration also enables sheath 136 to be advanced over stabilization device 250A without radially expanding sheath 136.

Stabilization device 250A includes a stabilization element 270 disposed adjacent the distal end of elongate body 132A. Elongate body 132B has a plurality of delivery platforms 160 proximal of stabilization elements 270 and is similar to elongate body 132 except as described below. In the illustrated embodiment, the stabilization element 270 comprises a plurality of elongated, axially oriented bands 274 separated by slots 278. The bands are sufficiently flexible to enable the bands to radially expand when compressive forces are applied to their proximal and distal ends. Radial expansion of the band 274 causes the outer surface thereof to engage the wall of the lumen at circumferentially spaced locations.

The stabilization device 250A also includes a linkage 282 and an actuation mechanism configured to apply a compressive force (indicated by the arrow in fig. 38) to the stabilization element 270. The link 282 may be a wire having a distal end coupled to the tip 172 and a proximal end coupled to the actuation mechanism. The actuation mechanism may be incorporated into the deployment system 46 of fig. 500 (discussed in detail below) or any other deployment system or device described herein.

The linkage 282 may be removed by providing a balloon or other actively expandable member at the stabilization element 270 so that the user may cause the balloon to expand the elongate axially oriented band 274 into engagement with the vessel wall. The bands 274 advantageously define gaps between the bands through which at least some blood may flow downstream of the stabilization element 270. This may minimize ischemia during surgery as compared to other more occlusive anchor devices.

An imaging device 286, such as a radiopaque band, may be located proximal of the stabilization element 270, e.g., between the stabilization element 270 and the distal-most delivery platform 160, to indicate to the clinician that the stabilization element 270 is distal of a lesion or treatment area.

b. Minimizing motion using passively expandable distal anchors

Passive anchor elements may provide stability to the delivery system in addition to or in lieu of actively actuating the anchor. The passive anchor element may be disposed on an exterior surface of the delivery system to minimize at least one of axial or radial deflection of the at least one delivery platform.

The configuration of FIG. 38 can also be used for passive deployment of the distal anchor means. For example, the stabilization element 270 may comprise a shape memory material. In one embodiment, the elongate, axially-oriented band 274 is formed of a shape-memory material and is configured in a radially-expanded state in the absence of circumferential constraint. Under constraints (e.g., sheath 136 over elongate axially oriented band 274), such a variation is delivered to a location adjacent to or distal to the treatment area or lesion. Relative movement between the sheath 136 and the elongate member 132B uncovers the elongate, axially oriented band 274 and allows it to return to its radially expanded configuration. This embodiment advantageously eliminates the need for the link 282.

Fig. 39-40 illustrate two passively deployed anchors that may be used with the delivery system 100C. Delivery system 100C is the same as delivery system 100 with some modifications to elongate body 132. In particular, an elongate body 132C is provided having a self-expanding member 300 disposed thereon. In fig. 39, self-expanding member 300 comprises a braided structure 304 having proximal and distal ends 308A, 308B connected to a portion of elongate body 132C between distal-most delivery platform 160 and distal tip 172. Braided structure 304 can be delivered within sheath 136 and deployed by providing relative motion between sheath 136 and elongate body 132C. In the absence of any circumferential constraint, the braided structure 304 has an expanded width that is greater than the size of the vessel in which the system 100C is deployed. Thus, passive (or self) expansion of the braided structure 304 creates engagement with the vessel wall. Subsequently, one or more staples 140 may be deployed in an accurate and controlled manner.

Another advantage provided by the braided structure 304 is that it allows some blood flow through the braided structure to maintain at least some perfusion of tissue downstream of the anchoring site. With respect to other more occlusive or fully occlusive anchors herein, a lumen may be provided as an alternative means to maintain perfusion. For example, if a balloon is used to anchor the delivery system, a lumen may be provided through the balloon to perfuse downstream tissue. Perfusion may not be required for rapid surgery.

Fig. 40 shows a self-expanding member 300 comprising a plurality of axially extending arms 320. Each arm 320 has a distal end 328 and a proximal end 324 coupled with the elongate body 132D. The elongated body 132D is shown without the tip 172, but may be provided with a tip as in any of the above embodiments. Each of the arms 320 is configured to be held by the sheath 136 in a low profile configuration, with the distal ends 328 of the arms 320 adjacent the elongate body 132D and extending radially away from the elongate body 132D when the sheath 136 is disposed at the proximal end of the arms 320. In the expanded position or configuration, as shown in fig. 40, the distal ends of the arms are positioned for attachment to a body lumen. Any number of arms may be provided. Arm 320 acts like a tripod to stabilize and position (e.g., center) elongate body 132D distal to delivery platform 160.

Fig. 41 illustrates another form of passive anchor that incorporates isolation that enhances the delivery system 100 from friction due to engagement of the system with the vasculature. This friction is greatly increased as the catheter assembly 104 traverses arbitrary bends in the vasculature. One technique for isolating abrasion and the system 100 is to provide an abrasion isolation sheath 340 disposed between the sheath 136 and the vasculature. Friction isolation sheath 340 may take any suitable form, but is preferably configured to prevent frictional forces along the outer surface of sheath 136 during placement of staples 140 from causing unwanted movement of elongate body 132.

One technique for separating sheath 136 from frictional forces due to bending is to construct an abrasive isolation sheath 340 of sufficient length to extend from an intravascular access site a (e.g., the femoral artery) to the treatment area. Fig. 41 shows that treatment zone Z may span iliac bifurcation B and provide vascular access not through the iliac arteries of the leg, either in the iliac arteries of the leg or distal to the iliac arteries of the leg. In other words, the distal end 344 of the frictional isolation sheath 340 is disposed beyond the bifurcation B or other bend T. Other treatment areas may be accessed using an abrasive isolation sheath 340. The length may be long enough to extend to the distal end of any additional bends below the iliac artery in the leg with or without an entry. In other words, the distal end 344 of the sheath 340, which is provided with frictional isolation, is beyond an arch or other bend. In some techniques, the friction release sheath may be configured with enhanced lubricity on its inner surface. The enhanced lubricity may reduce the frictional forces below a threshold to eliminate undesirable movement of the elongate body 132 due to such friction.

2. Structure and method for maintaining pitch

As described above, staples and other vascular devices that benefit from maintaining a predetermined minimum spacing may be deployed with the system 100. For example, the minimum spacing may be provided by a variety of different structures once stabilized, such as by any of the techniques described herein. For example, delivery platform 160 may assist in managing device spacing as needed. In some embodiments, proximal marker bands 168 each protrude radially out of elongate body 132 by an amount sufficient to present a distally facing shoulder that may abut staples 140 disposed on delivery platform 160. The shoulder may act like a plunger that provides a holding or pushing force against the proximal aspect of the nail 140. This holding or pushing force may prevent proximal migration of staples 140 as sheath 136 moves proximally relative to elongate body 132.

Fig. 42 illustrates other embodiments in which a delivery system 400 is provided that is adapted to deliver a vascular prosthesis comprising a plurality of discrete devices. System 400 includes an elongate body 404, an elongate bag 40, and a sheath 412. The elongate body 404 includes a distal end 414, a proximal end (not shown), and a plunger 416 disposed adjacent the distal end 414. The elongated bag 408 has a plurality of intravascular spikes 140 coupled thereto. The staples 140 may be disposed along the length of the elongated packet 408.

The sheath 412 has a proximal end (not shown) and a distal end 420 and may be positioned in a first position wherein the distal end 420 of the sheath 412 is disposed distal to at least a portion of the elongate bag 408. The first location may be a location where the entire packet 408 is disposed inside the sheath 412. For example, the distal end 424 of the packet 408 may be disposed inside the sheath 412 and at the distal end of the sheath 412 or proximal to the distal end of the sheath 412. The sheath 412 may be positioned in a second position, wherein the distal end 420 of the sheath 412 is disposed proximal to the elongate packet 408. Movement from the first position to the second position may be accomplished by proximal movement of the sheath 412 relative to the plunger 416, by distal movement of the plunger 416 relative to the sheath 412, or by synchronization of proximal movement of the sheath 420 and distal movement of the plunger 416. The plunger is moved or held stationary by applying a force to the proximal end of the elongate body 404.

As discussed above, the elongated packet 408 is configured to maintain a minimum spacing between adjacent staples during deployment (e.g., during any form of movement of the components of the system 400). The elongate packet 408 is also configured to allow expansion from a compressed configuration in which the elongate packet 408 is contained within the sheath 412. In the expanded state, the elongate bag 408 may engage the vessel wall.

In various embodiments, the elongate bag 408 can be configured to release the staples to expand toward the vessel wall upon deployment. The bag 408 may be configured with an elongated sleeve 428 and a ripcord (rip cord) 432. The preferred tear cord 432 is coupled to the sleeve such that separation of the tear cord 432 from the sleeve 428 allows the spike 140 to expand toward the vessel wall. Fig. 43 shows an embodiment of a sleeve 428 comprising a fabric structure 436, which may have a higher braid angle. For example, a braid angle of at least about 110 degrees may be used. In this embodiment, tear cord 432 may be configured as one or more unraveled cords (strings). Tear cord 432 may be actuated to release the restraining force of sleeve 428. For example, in a fabric embodiment, tear cord 432 detaches the sleeve, allowing staple 140 to release.

Tear cord 432 preferably has a proximal portion coupled to an actuator at the proximal end of the respective delivery device. Tear cord 432 may extend through a lumen (e.g., a dedicated lumen) within the delivery system and may be actively separated from the sheath or plunger if desired. The clinician may use such an actuator to apply force to tear cord 432 to unravel or otherwise deploy staple 140.

Another embodiment may be provided wherein the tear cord is removed. For example, the sleeve 428 may comprise the following structure: the structure softens when immersed in blood so that the structure passively releases the staples 140 shortly after deployment. The cannula 428 may comprise a bioabsorbable material or a non-reactive polymer that is left between the staple 140 and the vasculature. The entire deployed structure, including the staple 140 and the cannula 428, may be configured to absorb into the vasculature and, in some applications, eventually disappear into the patient. In other embodiments, the elongate packet 408 may be coated with a drug elution (e.g., coated with a bioabsorbable tear cord 432) as well as an elution retention sleeve 428 and peg. As tear cord 432 is absorbed, retained packet 408 is pressed against the vessel wall by the expanded spike and retained. In such an alternative embodiment, tear cord 432 may be only a region of fabric structure 436 (or one or more strands) rather than a structure distinct from structure 436.

In one embodiment of fig. 44, the elongated packet 408 comprises a plurality of staples 140 and a member 440 extending axially through a central region of each staple. A member 440 is coupled with each staple 140 to inhibit the staples from being in a low profile configuration, wherein the staples may be disposed in the sheath 136. Fig. 44 shows the plurality of staples 140 after separation from the elongate member 440 and after expansion into engagement with the wall of the vessel V. The elongate member 440 may be connected to the nail 140 in any suitable manner (e.g., by using one or more radially extending members 448). Members 448 are configured to inhibit expansion of staples 140 when the staples are disposed in sheath 136, but to rupture after deployment therefrom. The rupturing of the radial members 448 can be accomplished by any active mechanism (e.g., by cutting, untying, or activating a tear cord) or by a passive mechanism (e.g., by eroding the vasculature). After the radial elements 448 are separated from the staples 140, the staples can be moved away from the members 448 into a radially expanded configuration, providing clearance between the members 448 and the staples 140.

Member 440 can then be moved out of sheath 136 by providing relative motion between member 404 and sheath 136. In the embodiment shown, the distal end of the elongate member 404 is connected to the proximal end of the member 440 and acts as a plunger to push the packet 408 out of the sheath 136. In other embodiments, the elongate member 404 has a small distal end to be inserted through the staple 140 when the staple is in the low-profile configuration. The elongate member 404 may be coupled with the distal end of the member 440 of the elongate packet 408. In this configuration, the elongate member 404 acts on the distal end of the pack 408 rather than on the proximal end, as in the embodiment of fig. 42-43.

In each of the embodiments of fig. 42-44, a predefined and substantially fixed axial spacing is maintained between adjacent staples. Thus, the elongated packet provides a device spacing element that can provide accurate spacing between staples during placement. This provides the following advantages: such as minimizing vessel kinking, excess metal, and other problems associated with positioning the peg 140 too close together with other vascular prostheses.

3. Balloon dilatation

The balloon may also be used to deploy a plurality of staples in a controlled manner to have the proper spacing between the staples. Fig. 45 shows deployment system balloon 490 with staples 140 crimped thereon. The illustrated portion of the peg 140 is one of a plurality of repeating segments having mirror image counterparts as discussed above, with the other segments being omitted for clarity. Balloon 490 is used to deliver and expand staples 140 and may be referred to as a carrier balloon. The balloon 490 may be shaped or may contain more than one plastic that provides controlled inflation. Staples 140 and balloon 490 are carried to a repair site (not shown, but similar to that discussed above) inside the sheath. The balloon 490 expands as it exits the distal end of the sheath or after it exits the distal end of the sheath during deployment. Expansion of balloon 490 expands staples 140. In one variation of this system, non-self-expanding or partially self-expanding staples 140 are deployed using a balloon. For example, balloon 490 may expand to a threshold where a constraining structure disposed between staples 140 and sheath is broken. The rupture of the retention structure allows the nail 140 to expand. Balloon 490 may fully expand staples 140 (and the use of protrusions in balloon 494 discussed more below may raise the area of the staples to anchor more effectively), release staples 140 to self-expand, or provide some combination of balloon and self-expansion.

Another technique for controlled placement of the staples 140 is to expand the staples under radially outwardly directed pressure, such as by expansion of a balloon. Figure 45 shows balloon 490 with plaque tack 140 disposed thereon in an expanded state. Although a single balloon is shown, in one embodiment, the balloon is incorporated into each delivery platform 160 of the delivery system 100. Balloon 490 may have any suitable configuration, but is preferably configured to rotate the anchor of tack 140 into the plaque or other vascular malformation to remain against the vessel wall. For example, balloon 490 may include radially protruding regions 494 disposed on the expansible portion thereof. The radially protruding regions 494 are preferably configured to rotate the anchor 20 (see anchor 20 in fig. 5C) of the tack 140 out of the cylindrical plane containing the proximal and distal portions of the tack.

The protruding regions 494 may have any suitable configuration, such as a plurality of discrete protrusions disposed circumferentially around the balloon 490. The tab may be located below the anchor 20 of the nail 140, but does not extend completely below the marker 22. The projections can be configured such that as balloon 490 expands, the projections expand a greater amount such that staples 140 can be deformed from a generally cylindrical delivery shape to a configuration in which bridge 14 is rotated about an axis connecting the ends of the bridge. This rotation causes the anchor 20 to tilt away from the center of the vessel and into the plaque to be fixed.

In other embodiments, the protruding regions 494 may be a substantially continuous circumferential structure, such as ridges extending in all directions around the balloon. Preferably, in this configuration, in a radially disposed position between the anchor 20 and the longitudinal axis of the balloon, there is still greater radial protrusion of the balloon in the expanded state.

The height of the ledge area 494 is preferably at least about 0.05 mm. In other words, when the balloon is expanded to the diameter of the vessel in which the staples are to be placed, the protruding regions 494 have a radially outermost tip or portion that is at least about 0.05mm from the average surface of the balloon 490. Alternatively, if a plurality of protrusions are provided, the cylinder intersecting the tips of all the protrusions is preferably about 0.05mm in radial direction from the average radius of the balloon. In other embodiments, the height of the ledge area 494 is between about 0.05mm and about 0.4 mm. While in other embodiments, the height of the ledge area 494 is between about 0.07mm and about 0.4 mm. Still other embodiments provide that the height of the ledge area 494 is between about 0.1mm and about 0.2 mm. Balloon 490 may advantageously be paired with staples that are not self-expanding. Standard deformable stent materials such as stainless steel may be used. In some cases, it may be advantageous to combine the balloon expansion step with a self-expanding device. Thus, balloon 490 may also be used in conjunction with self-expanding staples. The additional height of the ledge area 494 may advantageously engage features of the tack 140 (e.g., the anchor 20 or bridge 14) to prevent the tack from sliding along the axis of the balloon. In a typical balloon, the length not encompassed by the prosthesis expands more than the length encompassed by the prosthesis, creating a "dog bone" shape when expanded. A dog bone shaped balloon may induce unwanted movement of a peg mounted thereon. As described above, the protruding region 494 may prevent such movement by engaging the peg. The balloon 490 may be configured to elute drugs beneficial in treatment, such as drugs that help minimize restenosis or inflammatory reactions.

Balloon 490 may also include a plurality of constraints, such as constraining bands 492, which limit the expansion of the balloon to certain areas of the balloon as shown in fig. 45A. For example, balloon 490 may be used with a series of non-self-expanding tacks 140 spaced along the length of balloon 490. Fig. 45A shows a portion of such a balloon. Because the balloon has a tendency to expand from one end, the constraining bands may limit this type of expansion and will concentrate the expansion in each area containing the staples 140. Balloon section 494, which does not contain staples or constraining bands, may be used to ensure proper spacing between staples and may form a barrier between successive staples as the balloon is expanded to its fully expanded position.

4. Deployment system

As discussed above in connection with fig. 4A, 32A, and 33A, various tools or components may be provided for the proximal end of the delivery system 100. Fig. 46-48D show additional details of these and other embodiments of a deployment system 500 for the delivery system 100. Deployment system 500 preferably includes a housing 504 that can be held by a user and that includes a trigger 508. Housing 504 is connected to the proximal end of catheter assembly 104, for example, to elongate body 132 and sheath 136 (see fig. 34) to impart relative movement between these two components. In certain embodiments, it is preferred that elongate body 132 be stationary and sheath 136 be retracted to provide relative movement. In other cases, however, this may be reversed, such that elongate body 132 is moved while sheath 136 is stationary.

In one configuration, the housing and trigger 504, 508 comprise a single deployment ratchet handle configuration that is manually driven. In this configuration, each time trigger 508 is activated, relative proximal movement of sheath 136 will expose one prosthesis (e.g., staple 140). The trigger 508 is preferably a spring loaded so that it springs back to its original position after being depressed.

a. Power to assist deployment device

As noted above, the use of multiple discrete prostheses may be advantageous for the treatment of various indications. For some treatments, the location of the treatment is remote from the location where the delivery system enters the vasculature or body cavity system. Both of these conditions increase the amount of force required to activate the trigger 508. For this to be the case and also to facilitate deployment, the deployment system may include a mechanical energy source 516 to generate the force necessary to provide relative movement of sheath 136 with respect to elongate body 132. Energy source 516 may be configured to generate approximately the same force at the distal end of system 100 for deploying one staple 140 or deploying multiple staples 140. The energy source 516 may be configured to generate a constant force over a stroke length that is more than twice the axial length of the staples disposed in the system 100. In some embodiments, energy source 516 is configured to maintain approximately the same speed of relative motion (e.g., sheath retraction) at the location of the distally located staples and proximally located staples.

The energy source 516 may contain various components and impart energy or power to the system. For example, in one embodiment, energy source 516 comprises a pneumatic cylinder that provides the desired distance to the sheath for controlling retraction. As shown in fig. 47, the energy source 516 may be external to the housing 504, e.g., containing a fluid channel connected to an external gas cylinder. In one variation, the gas is contained within enclosure 504 in a small vessel to provide the required energy. In these embodiments, the system is not under any stress until after the gas source is engaged.

To induce retraction of sheath 136 relative to elongate body 132 and indicia 168, proximal plunger 520 is coupled to sheath 136. The plunger 520 is also disposed within the housing 504 to form a portion of an enclosed space in fluid communication with the gas of the energy source 516. Deployment system 500 is configured such that plunger 520 moves proximally within housing 504 as a bolus of gas is delivered to this enclosed space. This proximal movement produces a corresponding proximal movement of sheath 136.

The energy source 516 need not be limited to a cylinder. In another embodiment, a compression spring adapted to generate a substantially constant force is provided. Preferably, the spring is configured to provide sufficient force over the longitudinal length that is sufficient to expose as many prostheses (e.g., staples 140) as desired for treatment. This distance or stroke length may be between about 10mm and about 200mm (e.g., for system carry or operation to deploy up to 20 staples). In certain embodiments, the stroke length is between about 8mm and about 80mm (e.g., for system carry or operation to deploy up to 10 staples). In other embodiments, the stroke length is between about 7mm and about 10mm (e.g., for system carry or operation to deploy 1 staple). In one arrangement, the spring is tensioned before sheath 136 is retracted. In another embodiment, the spring is tensioned prior to use by the clinician (e.g., at the factory).

As discussed further below, it may be desirable to be able to select the number of devices to be deployed. In this case, deployment system 500 may be configured such that only a portion of the travel of the spring is engaged. When the number of staples to be deployed is selected, the handle will automatically engage the correct length of the spring and will therefore provide a suitable amount of force. As discussed in section iv (a) (4) (b) below, a selector may be included to enable the clinician to select a series of staples 140 to be deployed, e.g., a subset of the total number of staples on the delivery system to be deployed in a given deployment event.

A spring-like force can also be generated by compressing the gas. For example, a structure similar to the plunger 520 may be pushed and held at the distal end within the handle and released only when deployment occurs. The compressed gas may cause the plunger to move proximally along the sheath. This effect can be seen as a form of spring rebound.

Another spring configuration that may be used includes a bellow spring, which may be advantageous in designs that require a longer movement to retract the sheath. In this configuration, the energy source 516 is adapted to act at two points across the bellows spring. The energy source may comprise a gas or liquid that acts under pressure on one end of the bellows to facilitate movement of the bellows. The bellows retracts a distance that is several times the distance traveled by the energy source spring, since the energy spring is allowed to rebound. This system provides a transition between a high force spring and controlling a long distance low force retraction.

Another option is to use a rotary spring to drive the lead screw. The spring may be pre-tensioned and connected to the lead screw. Sheath 136 is then connected to a follower (follower) that moves as the lead screw rotates. This will allow the rotational movement provided by the spring to be translated with the appropriate force by the lead screw into proximal (linear) movement of the sheath.

b. Selector for multi-prosthesis deployment

For example, an elongated treatment region, which may contain plaque or an elongated vascular flap, may be treated with a plurality of staples 140. In certain operations, it is possible to know, through visualization or other surgical planning tools, the number of staples or prostheses needed to provide adequate treatment. For such operation, the deployment system 500 may include a selector 532 to determine the number of prostheses or staples to be deployed, as shown in FIG. 48A. In one form, selector 532 may comprise a marker line 534 on one or more of elongate body 132 and sheath 136. These marker lines may provide a clinician holding the handle 11F, fixation device 108, or housing 504 with a visual cue as to how many staples have been deployed.

Figure 32A shows a marker line 534 disposed on the proximal end of elongate body 132. In this embodiment, the tuohyborst adapter 208 may be used as a selector. Proximal movement of sheath 136 may cause tuohy borst adaptor 208 to pass through each of the plurality of marker wires 534. Each time the tuohy borst adaptor 208 passes the flag line 534, one of the staples 140 is exposed and may be deployed. Thus, the user can know how many staples 140 are deployed and how much remains to be deployed by observing the position of the tuohy borst adapter 208 relative to the plurality of marker lines 534. The number of flag lines 534 exposed and not covered by the tuohy borst adaptor 208 may indicate the number of staples 140 remaining to be deployed.

In some embodiments, the length of sheath 136 may be related to the location of marker 534 on elongate body 132 and the location of delivery platform 160. For example, sheath 136 may be sized such that movement of the sheath from first marker wire 534 to second marker wire 534 may expose one delivery platform 160, or a substantial portion of the delivery platform. In some embodiments, the delivery platform comprising the distal marker band may have a length L1, and L1 may correspond to a length L2 from the distal end of the first marker wire to the distal end of the second marker wire. In some embodiments, marker bands 168 may be spaced apart by the same distance as marker line 534. In some embodiments, the marker lines 534 may be spaced apart by a distance greater than the distance between marker bands 168 or the spacing may be maintained as the size of the marker lines 534 gradually increases. In this manner, the spacing between the marker wires, or the marker wires 534 themselves, may accommodate differences in the elasticity of the sheath 136 and elongate body 132, and/or differences in the frictional forces between the sheath and its environment within the vessel, which may result in the distal end of the sheath experiencing less movement than the proximal end. In some embodiments, the spacing between the distal ends of the marker lines 534 may steadily increase from the first two most distal marker lines 534 and the next proximally spaced marker line 534.

In some embodiments, the marker lines 534 are different tick marks. In other embodiments, the marker line 534 may be a different region, such as a region of a different color. Another way to accommodate the elasticity of the sheath is to indicate with the marker line 534 that deployment of the staples 140 will occur when the proximal end of the sheath is within the field or between the graduation marks. The distance between delivery platforms 160 and the size of marker bands 168 may be configured with marker wires 534 to accommodate the expected elasticity of sheath 136.

Fig. 4A shows that the marker line can also be placed on the handle 11F. In particular, handle 11F is provided with a series of marker lines 534 that indicate how far sheath 13 has been moved. Each time the actuator 11G moves past the marker line 534, the other staple 140 moves out of the sheath 13 and can be deployed.

In certain embodiments, it is preferable to configure selector 532 to prevent the following: allowing deployment of more than a selected number of staples 140. In these embodiments, selector 532 further comprises a limiter 536 that prevents the deployment of more than a preselected number of staples. Fig. 48A shows that in one embodiment, the limiter 536 includes a slidable stop 538 that can be disposed about the proximal end of the elongate member 132. Locking means, such as thumb screws, are provided for securing the limiter 536 to the elongate member 132. If sheath 136 is moved proximally into contact with stop 538, a visual window 540 in limiter 536 shows a marker (indicia) of how many staples will be deployed, how much remains in the system or some other useful indicator of the struts that are deployed. In this case, a "1" is indicated if the limiter 536 is disposed at the proximal end of the elongate body 132. This informs the clinician that a staple will be deployed when the sheath 136 contacts the stop 538.

FIG. 48B illustrates another variation, wherein relative rotation of the proximal end of sleeve 136 and a selector 560 disposed within housing 504 may enable a user to select the number of prostheses (e.g., staples 140) to be deployed. In one variation, selector 560 includes a rod 564 that extends into a lumen formed in sheath 136. The rod includes a pin or other radial projection 568 that extends outwardly to one of a plurality of recesses 572 provided on the inner surface of the sheath 136. The recess includes a proximal outward facing surface 576. Each notch 572 is progressively further from the proximal end of the sheath 136 in a counterclockwise direction as shown. Each progressively further recess 572 allows for additional increments of axial movement of the sheath 136 relative to the pin 568. Each increment of axial movement corresponds to the amount of movement required to distally expose one delivery platform 160 and corresponding staple 140. By rotating sheath 136 relative to the pin from the position shown according to arrow a, a greater number of staples can be deployed in a single stroke. Relative rotation may be provided by coupling a lever 564 with a dial with an indicator disposed on the outside of the housing 504.

In a variation of the embodiment of fig. 48B, selector 560 may be configured as a sheath disposed about cannula 136. Sheath 136 can be modified to include an outwardly projecting pin similar to pin 568 and a sleeve that can be modified to have a notch. In this configuration, the structure labeled "564" in fig. 48 is a sheath and the structure labeled "136" is a sleeve disposed around the sheath.

Fig. 48C illustrates a deployment system 600 that can be provided with a housing similar to that shown in fig. 46. The system includes a source of mechanical energy and a selector for selecting the number of staples to be deployed. The system includes an actuator 604 coupled to an energy storage device 612 by a cable 608. The actuator 604 is mounted on a rigid body 610, the rigid body 610 may also be coupled with the elongate body 132. The energy storage device 612 may include a rotational spring that actuates a lead screw. More particularly, the cable 608 is wound on a drum 610 that is rotatable about the axis of the base screw 614. The spring is coupled to the drum 610 such that as the drum rotates to unwind the cable 608, the spring loads and after the tension is removed from the cable, the spring causes the drum to rotate in the opposite direction, winding the cable back onto the drum. The length of cable 608 wound on the barrel is equal to or greater than the linear distance from the distal end of the distal-most delivery platform 160 to the proximal end of the proximal-most delivery platform 160. The selector includes a plurality of stops 620 disposed at the proximal end of the sheath 136. The flights may be activated or deactivated. The first stop 620A is located closest to the distal end of the sheath 136 and allows the sheath to move only an amount sufficient to deploy one staple 140. After the first staple is deployed, the first stop 620A may be deactivated and the second stop 620B may be activated by pressing into the rigid body 606. The second stop allows the sheath 136 to travel a distance sufficient to expose the second distal-most delivery platform 160 and the staples 140. After deployment of the second staple, second stop 620B may be deactivated and third stop 620C may be activated by pressing into rigid body 606. The third stop allows sheath 136 to travel a distance sufficient to expose third distal-most delivery platform 160 and staples 140. After the third staple is deployed, third stop 620C may be deactivated and fourth stop 620D may be activated by pressing into rigid body 606. The fourth stop allows sheath 136 to travel a distance sufficient to expose fourth distal-most delivery platform 160 and staples 140. Additional stops 620 may be provided if more than four pegs or platforms are provided. The energy stored in the energy storage device 612 causes the actuator 604 to automatically return to the original position for further triggering.

Fig. 48D shows another concept that can be used for the deployment sequence, where only one staple is deployed at a time. This arrangement is similar to a bolt action mechanism. The deployment system includes a selector device 660 having a plurality of tines 664 axially spaced along rigid body 666. These tines 664 provide a rigid stopper structure. A movable member 668 coupled to the proximal portion of the sheath 136 is disposed between adjacent tines 664, e.g., the distal end of the "2" tine 664, between the "2" and "3" tines, etc. Prior to deployment of the staple 140, the movable member 668 can be disposed proximal to the "2" tines but adjacent to the "2" tines. The energy source driven actuator can be triggered, after which sheath 136 and movable member 668 coupled thereto will slide proximally. The movable member 668 will slide into contact with the "3" tines. This provides a stiff barrier and may be useful if a relatively high power energy source is used. To deploy the additional staples, the movable member 668 will be moved to "No. 4" tines, "No. 5" tines, and "No. 6" tines in sequence.

5. Shuttle deployment device

Shuttle deployment device 700 as shown in fig. 49 may have one or more delivery platforms 160. As discussed above, the delivery platform 160 may include marker bands 168 at one or both ends thereof. A set of tracks, fingers, or tines 702 may extend from one end of each marker band 168. In the embodiment shown, there are 4 tracks 702, however, a greater or lesser number of tracks may be used. The track 702 extends distally from the proximal marker band 168A. In another embodiment, the track 702 extends proximally from the distal marker band 168B. The proximal and distal marker bands 168A, 168B are shown in fig. 36A and may be proximal and distal portions of a single band or axially spaced apart separate bands. In addition, only one set of tracks 702 is shown. However, it should be understood that in other embodiments, a track set 702 may be provided for each delivery platform 160. The track 702 may have a compressed position, for example, when it is within the sheath 136, and an expanded position in which the track is unconstrained. In the expanded position, the track may be curved, flared, angled, or otherwise configured such that the dimension of the shuttle 700 transverse to the longitudinal axis of the elongate member 132 decreases proximally along its length.

When the sheath 136 is retracted, the tracks move radially outward toward the vessel wall to the expanded position shown. This may center the catheter and establish a ramp or gradually increasing diameter to guide the positioning and expansion of the staples 140. As the staples 140 expand, the staples may slide down the track into position in the vessel wall. Thus, since the struts are limited to the amount of expansion by the radial tracks, the radial expansion of the staples 140 is controlled. The staples 140 may be crimped around the tracks 702 or may be crimped with some tracks inside the staples 140 and some tracks around the tracks.

Shuttle 700 may be disposed at the distal end of elongate body 132. As shown, shuttle 700 has a plurality of gaps between a plurality of rails 702. These gaps may be used to help properly position the staples 140. For example, the anchors, markings, and/or other features of the staples 140 may protrude radially through the gap such that a portion of the staples are radially between the tracks and the longitudinal axis of the elongate member and another portion protrudes to a radial position circumferentially between (or beyond) adjacent tracks. In this position, at least a portion of the track may be considered to be disposed radially between a portion of the staple and the longitudinal axis of the elongate member 132.

This configuration may provide a number of benefits, such as preventing rotation and providing additional control over the placement of the staples 140 in the vasculature. The gap may also allow the anchor portion of the staple (anchor 20) to be connected to the vasculature at the distal end of the shuttle device 700 or track 702.

In some embodiments, the track 702 of the shuttle is biased toward the closed position. Also, the staples 140 may be self-expanding staples that are biased to move toward their expanded configuration. When the self-expanding staples are loaded into the shuttle, the two opposing offsets create stored energy in the shuttle when the sheath is in place and both are confined in place. The bias of the staples is greater than the bias of the tracks so that the tendency to collapse is slightly less than the energy of the staples to expand. Thus, when the sheath is retracted from the delivery platform 160, the reaction force may provide controlled expansion as the staples exit the distal end of the delivery catheter. This advantageously reduces or eliminates too rapid expansion of the staples 140, which can lead to unpredictable placements.

Use of plaque tack following drug eluting balloon angioplasty

The use of a plaque tack device can be combined with the use of Drug Eluting Balloon (DEB) angioplasty to manage post angioplasty exfoliation and avoid the need for a stent. In DEB angioplasty, drug eluting or drug coated balloons are prepared in a conventional manner. The drug may be one or a combination of bioactive agents for various functions, such as anti-thrombotic, anti-mitotic, anti-proliferative, anti-inflammatory, healing promoting or other functions. DEBs are delivered over a guidewire that passes through an occluded or stenotic region in the vascular system. When the DEB is suitable for drug coating and the desired result, the DEB is inflated to a specific pressure and for a period of time, consistent with manufacturer guidelines for therapeutic purposes, and then deflated and removed. At this stage, the drug from the DEB is transferred to the vessel wall. The integrity of the artery and the smoothness of the vessel surface are then assessed at the balloon-inflated site using intravascular imaging by ultrasound. The presence of lesions along the surface may indicate exfoliation, lifting of plaque, rupture of tissue, irregularities of the surface. Plaque pegs are used to pin damaged, ruptured, exfoliated, or irregular vessel surfaces. This allows the continuation of a "stentless" environment even if damage to the vessel has occurred due to balloon angioplasty.

At this stage, the drug from the DEB is transferred to the vessel wall. Controls are administered into the vessel under fluoroscopic guidance or other methods (e.g., intravascular ultrasound) to assess the integrity of the artery and the smoothness of the vessel surface at the site of balloon inflation. In some cases, one or more of these completed studies will demonstrate the presence of lesions along the surface at the balloon inflation site. This damage may include denudation, lifting of plaque, rupture of tissue, surface irregularities.

The plaque tack delivery catheter is loaded with a plurality of tacks that can be placed at the discretion of the operator and advanced over the guidewire in the vessel to a location where spalling or rupture or irregularities occur. The location is specifically and carefully determined using angiography. One or more plaque pegs are deployed at one or more locations of the lesion. More than one nail may be placed to pin the primary exfoliation. If more than one staple is placed, the staples may be placed according to the rules of the proper spacing of the staples only. That is, the staples should be at least one staple axial length apart. After placement of the staples, the staples are further expanded into the vessel wall using a standard angioplasty balloon or a drug eluting balloon or a drug coated balloon (which may also be a separate (separate) device or integral to the delivery system). The purpose of the staples is generally not to hold open the vessel lumen, but to staple against the uneven or spalled surface of the vessel. This "repair strategy" allows regression of the damage created by the drug eluting or drug coated balloon without the need for stent placement, thereby maintaining a "stentless" environment.

As a further measure, the plaque tack device itself can be used to deliver drugs to the blood vessel, as described above. In addition to delivering the drug from the anchor, the staples may be coated with a drug prior to staple deployment. The purpose of this is to allow the peg to elute one or more bioactive agents that have a positive effect on the blood vessels.

One or more staples deployed according to the present invention may be coated or otherwise carry a drug to elute over time at the deployment site. A variety of therapeutically useful agents may be used, including, but not limited to, for example, agents for inhibiting restenosis, agents that inhibit plaque accumulation, or agents that promote endothelialization. Some suitable agents may include inhibitors of smooth muscle cell proliferation, such as rapamycin, angiostatin, and monoclonal antibodies capable of blocking smooth muscle cell proliferation; anti-inflammatory agents such as dexamethasone, prednisolone, corticosterone, budesonide, estrogen, sulfasalazine, acetylsalicylic acid and mesalamine, lipoxygenase inhibitors; calcium entry blockers, e.g. verapamil, diltiazemAnd nifedipine; antineoplastic/antiproliferative/antimitotic agents, such as paclitaxel, 5-fluorouracil, methotrexate, doxorubicin, daunorubicin, cyclosporine, cisplatin, vinblastine, vincristine, fall alcoxides, epothilones (epothilones), endostatin, angiostatin, squalamine, and thymidine kinase inhibitors; l-arginine; antimicrobial agents such as triclosan (astriclosan), cephalosporins, aminoglycosides, and nitrofurantoin (nitrofurazone); anesthetics such as diureticsLidocaine, bupivacaine and ropivacaine; nitric Oxide (NO) donors such as linsidomine, molsidomine, NO-protein adducts, NO-polysaccharide adducts, polymeric or oligomeric NO adducts or chemical complexes; anticoagulants such as D-Phe-Pro-Arg chloromethyl ketone, RGD peptide-containing compounds, heparin, antithrombin compounds, platelet receptor antagonists, antithrombin antibodies, antiplatelet receptor antibodies, enoxaparin (enoxaparin), hirudin, warfarin sodium (Warafin sodium), dicoumarin, aspirin, prostaglandin inhibitors, platelet inhibitors, and tick antiplatelet factors; interleukins, interferons, and free radical scavengers; vascular cell growth promoters such as growth factors, growth factor receptor antagonists, transcriptional activators (transcriptional activators), and translational promoters; vascular cell growth inhibitors, such as growth factor inhibitors (e.g., PDGF inhibitors-trapidil), growth factor receptor antagonists, transcription inhibitors, translation inhibitors, replication inhibitors, inhibitory antibodies, antibodies directed against anti-growth factors, bifunctional molecules consisting of growth factors and cytotoxins, bifunctional molecules consisting of antibodies and cytotoxins; tyrosine kinase inhibitors, chymotryptic inhibitors (e.g., tranilast), ACE inhibitors (e.g., enalapril), MMP inhibitors (e.g., Ilomastat (Ilomastat), Metastat), GP IIb/IIIa inhibitors (e.g., Intergrilin, abciximab), hydroxytryptamine antagonists (serintin antagnonis), and 5-HT uptake inhibitors; a cholesterol lowering agent; a vasodilator; agents that interfere with endogenous vasoactive mechanisms. Polynucleotide sequences that may also act as anti-restenosis agents, such as p15, p16, p18, p19, p21, p27, p53, p57, Rb, nFkB and E2F decoys, thymidine kinase ("TK"), and combinations thereof, and other agents useful for interfering with cell proliferation. The choice of active agent may take into account the desired clinical outcome and the nature of the particular patient's circumstances and contraindications. Any of the staples disclosed herein, with or without a drug, may be made of a bioabsorbable material. Various polymeric carriers, binding systems or other coatings that allow for controlled release of active agents from staples or coatings thereof are well known in the art of coronary stents and are not important hereinAnd (5) repeating.

In summary, plaque tacks can be used to retain plaque after balloon angioplasty to treat atherosclerotic occlusive disease, while avoiding the problems associated with the use of stents due to the installation of large amounts of foreign material in the body that can cause problems with injury, inflammation, and/or restenosis of the site. In contrast to stents, plaque tack devices minimize material structure while only being installed at one or more plaque ablation sites that need to be maintained. Focal elevating elements on the periphery of the peg minimize the contact surface area of the plaque peg with the vessel wall and reduce the risk of causing plaque flaking or damage to the vessel wall. This approach provides the clinician with the ability to perform minimally invasive treatment after angioplasty and produces stent-like results without the use of a stent.

Although the present invention has been disclosed in the context of particular embodiments and examples, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof. In addition, while various modifications of the invention have been shown and described in detail, other modifications, which are within the scope of this invention, will be readily apparent to those of ordinary skill in the art based upon this disclosure. It is also contemplated that various combinations or subcombinations of the features and aspects of the embodiments may be made and still fall within the scope of the invention. Thus, it should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the disclosed invention. Therefore, it is intended that the scope of the invention herein disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow.

Similarly, this method of disclosure is not to be interpreted as reflecting an intention that any claim requires more features than are expressly recited in that claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of any single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment.

Claims (24)

1. A self-expanding endoluminal device configured for precise positioning during deployment within a vessel, the endoluminal device having a longitudinal axis extending between a distal end and a proximal end, the endoluminal device configured for radial compression and expansion comprising:

a first undulating ring disposed at the distal end extending circumferentially about the longitudinal axis, the first undulating ring comprising a plurality of struts, a plurality of inner apices, and a plurality of outer apices, wherein at least two struts are connected at one of the apices, the outer apices being distal to the inner apices; and

a proximal end connected to the internal apex;

wherein the endoluminal device is configured for delivery such that the first undulating ring is at least partially expandable while the proximal portion remains compressed, in which position:

a first strut of the plurality of struts extending at a radially outward angle from the longitudinal axis, the first strut connected to the compressed proximal end portion;

a second strut and a third strut of the plurality of struts are connected to the first strut and extend parallel to the longitudinal axis, the second strut and the third strut form a leg and the endoluminal device includes a plurality of such legs configured to extend parallel to the longitudinal axis when the endoluminal device is in such partially expanded position, the legs being positioned circumferentially about the longitudinal axis and configured to precisely position and orient the endoluminal device within the vessel as the endoluminal device is further expanded and deployed within the vessel.

2. The endoluminal device of claim 1, wherein the proximal portion comprises a second undulating ring disposed at the proximal end extending circumferentially about the longitudinal axis.

3. The endoluminal device of claim 2, wherein the proximal portion further comprises a plurality of bridging members connecting the first undulating ring and the second undulating ring.

4. The endoluminal device of claim 3, wherein each of the bridge members comprises at least one anchor.

5. The endoluminal device of claim 4, wherein the at least one anchor is configured such that partial expansion of the endoluminal device to the partially expanded position causes the anchor to move out of plane from the remainder of the compressed proximal portion.

6. The endoluminal device of any one of the preceding claims, wherein the proximal portion comprises a plurality of anchors.

7. The endoluminal device of claim 6, wherein each anchor of the plurality of anchors is configured such that partial expansion of the endoluminal device to the partially expanded position causes the anchor to move out of plane from the remainder of the compressed proximal portion.

8. The endoluminal device of any of the previous claims, wherein the second strut and the third strut are connected at a first of the plurality of internal apices.

9. The endoluminal device of claim 8, wherein the first internal apex is located distal to a connection between the first strut and the proximal portion.

10. The endoluminal device of claim 9, wherein the first strut is connected to the proximal portion at a second of the plurality of internal vertices such that the second internal vertex is proximally spaced from the first internal vertex.

11. A system comprising the endoluminal device of any of the previous claims and a delivery device, wherein the delivery device comprises a sheath configured to surround the endoluminal device when the endoluminal device is in a compressed position within the delivery device.

12. The endoluminal device of any of the previous claims wherein the endoluminal device comprises a staple or a stent.

13. An endoluminal device, comprising:

a first circumferential member disposed at a distal end of the endoluminal device, the first circumferential member having a first outer apex disposed between a first strut and a second strut, a second outer apex disposed between a third strut and a fourth strut, a first inner apex disposed between the second strut and the third strut, and a second inner apex disposed adjacent the fourth strut;

a second circumferential member disposed at a proximal end of the endoluminal device; and

a bridge member having a first end coupled with the second internal apex and a second end coupled with the second circumferential member, the bridge member having a plaque anchor disposed at or adjacent a central region of the bridge member;

wherein the first inner apex point extends a first axial distance from the central region of the bridge member and the second inner apex point extends a second axial distance from the central region of the bridge member, the first distance being greater than the second distance such that the second strut and the third strut form a leg that is extendable outwardly from the second circumferential member when the endoluminal device is in a partially expanded position, the leg being substantially parallel to the longitudinal axis of the endoluminal device.

14. An endoluminal device, comprising:

a first circumferential member disposed at a distal end of the endoluminal device, the first circumferential member having a first outer apex disposed between a first strut and a second strut, a second outer apex disposed between a third strut and a fourth strut, a first inner apex disposed between the second strut and the third strut, and a second inner apex disposed adjacent the fourth strut; and

a second circumferential member disposed at a proximal end of the endoluminal device;

wherein the first inner apex is positioned away from the second inner apex such that the second strut and the third strut form a leg that is extendable outwardly from the second circumferential member when the endoluminal device is in a partially expanded position, the leg being substantially parallel to a longitudinal axis of the endoluminal device.

15. The endoluminal device of claim 14, wherein a plurality of the first and second outer apices are aligned along the longitudinal axis.

16. The endoluminal device of claim 14, wherein a plurality of the first outer apices are proximally spaced from a plurality of the second outer apices along the longitudinal axis.

17. The endoluminal device of any one of claims 14-16, further comprising a bridge member extending between the first and second circumferential members.

18. The endoluminal device of claim 17, wherein the bridge member has a first end connected to the second inner apex and a second end coupled with the second circumferential member.

19. The endoluminal device of claim 17, further comprising at least one anchor positioned on the bridge member.

20. A method of placing an endoluminal device comprising:

providing a catheter system comprising an elongate body having a delivery platform disposed adjacent a distal end of the elongate body and a marker band at a distal end of the delivery platform, the delivery platform having an endoluminal device disposed thereon and an outer sheath over the endoluminal device;

advancing the distal end portion of the elongate body through the vasculature of the patient until the marker band is located at the treatment area;

visualizing the marker band to confirm the position of the delivery platform relative to the treatment area;

retracting the outer sheath while maintaining the position of the elongate body such that a plurality of legs of a first circumferential member disposed at a distal end of the endoluminal device are released from the delivery platform prior to release of the remainder of the endoluminal device, the first circumferential member comprising:

a first outer apex disposed between a first strut and a second strut, a second outer apex disposed between a third strut and a fourth strut, a first inner apex disposed between the second strut and the third strut, and a second inner apex disposed adjacent to the fourth strut, the foot comprising:

the first internal apex, the first external apex, the second strut, and the third strut, the legs assuming a pre-fully deployed position prior to full expansion.

21. The method of claim 20, further comprising engaging a vessel wall with the plurality of legs.

22. The method of claim 21, wherein the plurality of legs are engaged with the vessel wall before the remainder of the endoluminal device is engaged with the vessel wall.

23. The method of any one of claims 20-22, further comprising retracting the outer sheath an additional number of times to release additional endoluminal devices.

24. The method of any one of claims 20-23, further comprising selecting an increment corresponding to a number of endoluminal devices to be deployed and retracting the sheath by the selected increment.