US20100234885A1 - Patent foramen ovale closure system - Google Patents

Abstract

A patent foramen ovale closure device, method of delivering and a delivery system are provided. The device may include a closure device releasably connectable to an actuator. The device may include a proximal segment, an intermediate segment and a distal segment. When delivered, the proximal segment and intermediate segment form a first clip-shaped portion sized and configured to be positioned over a septum secundum of the patent foramen ovale, and the intermediate segment and distal segment form a second clip-shaped portion sized and configured to be positioned over a septum primum of the patent foramen ovale.

Description

CROSS-REFERENCE TO RELATED APPLICATION
• This application is a Continuation of co-pending U.S. patent application Ser. No. 10/771,845, filed on Feb. 4, 2004, which claims the benefit of U.S. Provisional Application No. 60/445,088, filed Feb. 4, 2003, the entirety of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
• 1. Field of the Invention
• Embodiments of the present invention relate to methods and devices for closing a body lumen or cavity and, in particular, for closing a patent foramen ovale.
• 2. Description of the Related Art
• Embolic stroke is the nation's third leading killer for adults, and is a major cause of disability. There are over 700,000 strokes per year in the United States alone. Of these, roughly 100,000 are hemorrhagic, and 600,000 are ischemic (either due to vessel narrowing or to embolism). About 50,000 of the ischemic strokes are believed to be caused by a patent foramen ovale. However, the risk of recurrent stroke is higher in patients whose strokes are caused by a patent foramen ovale.
• Pharmacological therapies for stroke prevention such as oral or systemic administration of warfarin or the like have been inadequate due to serious side effects of the medications and lack of patient compliance in taking the medication.
• In general, the heart is divided into four chambers, the two upper being the left and right atria and the two lower being the left and right ventricles. The atria are separated from each other by a muscular wall, the interatrial septum, and the ventricles by the interventricular septum.
• Either congenitally or by acquisition, abnormal openings, holes or shunts can occur between the chambers of the heart or the great vessels (interatrial and interventricular septal defects or patent ductus arteriosus and aortico-pulmonary window respectively), causing shunting of blood through the opening. A patent foramen ovale is a condition wherein an abnormal opening is present in the septal wall between the two atria of the heart. Blood can flow directly between these two atria, compromising the normal flow of blood and efficiency of the patient's heart. The deformity is usually congenital, resulting from a failure of completion of the formation of the septum, or wall, between the two sides during fetal life when the heart forms from a folded tube into a four-chambered, two unit system.
• In contrast to other septal defects which tend to have a generally longitudinal axis, a patent foramen ovale tends to behave like a flap valve. Accordingly, the axis of the patent foramen ovale tends to be at an angle, and almost parallel to the septal wall.
• These deformities can carry significant sequelae. For example, with a patent foramen ovale, blood is shunted from the left atrium of the heart to the right, producing an over-load of the right heart. In addition to left-to-right shunts such as also occur in patent foramen ovale, the left side of the heart has to work harder because some of the blood which it pumps will recirculate through the lungs instead of going out to the rest of the body. The ill effects of these defects usually cause added strain on the heart with ultimate failure if not corrected.
• Previously, patent foramen ovale have required relatively extensive surgical techniques for correction. To date the most common method for closing intracardiac shunts, such as a patent foramen ovale, entails the relatively drastic technique of open-heart surgery, requiring opening the chest or sternum and diverting the blood from the heart with the use of a cardiopulmonary bypass. The heart is then opened, the defect is sewn shut by direct suturing with or without a patch of synthetic material (usually of Dacron, Teflon, silk, nylon or pericardium), and then the heart is closed. The patient is then taken off the cardiopulmonary bypass machine, and the chest is closed.
• In place of direct suturing, closures of a patent foramen ovale by means of a mechanical prosthesis have also been disclosed. A number of these devices, designed for closures of interauricular septal defects, have been used to correct patent foramen ovale.
• Although these devices have been known to effectively close other septal defects, there are few closure devices which have been developed specifically for closing patent foramen ovale. Although these devices have been effective in some cases, there is still much room for improvement.
• Notwithstanding the foregoing, there remains a need for a method and improved apparatus for correcting patent foramen ovale.
SUMMARY OF THE INVENTION
• Embodiments of the present invention provide a minimally invasive closure device for closing a patent foramen ovale. Improved delivery and positioning systems are also provided.
• In accordance with one embodiment, a closure device for closing a patent foramen ovale is provided. The device includes a proximal end, a distal end, a proximal segment, an intermediate segment, and a distal segment, wherein each of the segments is sequentially aligned. The device has a generally elongate configuration and a clip configuration. When the device is in its elongate configuration, the proximal and distal ends are pulled away from each other such that the proximal segment, intermediate segment, and distal segment become relatively more linear. When the device is in its clip configuration, the proximal segment and intermediate segment are drawn into a first clip-shaped portion sized and configured to be positioned over a septum secundum of the patent foramen ovale. The intermediate segment and distal segment are drawn into a second clip-shaped portion sized and configured to be positioned over a septum primum of the patent foramen ovale. The first clip-shaped portion and the second clip-shaped portion provide a force against the septum primum and septum secundum to pinch the two relatively closer together.
• In one embodiment, the closure device may be formed from a wire structure, more preferably one integral wire. In one embodiment, the proximal and distal segments are identical in shape, and may have identical shapes that form mirror images of each other across the patent foramen ovale to equally apply compressive force to both sides of the patent foramen ovale. In another embodiment, the proximal segment has a larger dimension than the distal segment, and more preferably has both a greater length and width than the distal segment. The distal segment may include a pair of wings adapted to extend over the tip of the septum primum. The device may also include loops, eyelets or other structure adapted for releasable engagement with a delivery system, as described below. The device may also include anchors or other tissue engaging structures to facilitate securement of the device in the patent foramen ovale.
• In accordance with another embodiment, a closure device for closing a patent foramen ovale is provided. The device includes a proximal segment, a distal segment, and an intermediate segment which may be integrally formed, preferably from an integral wire structure. A covering, sleeve or laminate structure is provided on at least one of the segments of the device. In one embodiment, a sleeve is provided over the intermediate segment and is adapted to be positioned in the tunnel of the patent foramen ovale. In another embodiment a laminate structure may be provided over at least the proximal or anterior portion. The sleeve may be made of a material that facilitates cellular in-growth, such as ePTFE.
• In accordance with one embodiment, a method of closing a patent foramen ovale having a septum primum and a septum secundum is provided. The method includes providing a closure device having a proximal end and a distal end and having a generally elongate configuration and a clip configuration. When the device is in its elongate configuration, the proximal and distal ends are pulled away from each other, and when the device is in its clip configuration the device has generally an S-shape. The device is releasably attached relative to a delivery device. The device is then delivered to the patent foramen ovale with the delivery device, the closure device being held relative to the delivery device in its elongate configuration. The closure device is deployed in the patent foramen ovale, such that the device when deployed includes a first clip-shaped portion positioned around the septum secundum and a second clip-shaped portion positioned around the septum primum.
• In accordance with a further embodiment, a method of closing a patent foramen ovale having a septum primum and a septum secundum in provided. The method includes providing a closure device having a proximal end, a distal end, a proximal segment, an intermediate segment and a distal segment. The method further includes deploying the closure device within the patent foramen ovale such that the distal segment lies along a surface of the septum primum within the left atrium of the patient. The proximal segment preferably lies along a surface of the septum secundum within the right atrium of the patient. The intermediate segment preferably lies in a channel or tunnel between the septum primum and the septum secundum. When the closure device is deployed, it exerts a force between the proximal segment and intermediate segment and between the intermediate segment and distal segment to draw or pinch the septum primum and septum secundum together.
• In accordance with another embodiment, a method of closing a patent foramen ovale is provided. The method includes positioning a closure device at a patent foramen ovale and deploying the closure device, such that the septum primum and septum secundum are secured together by the closure device.
• In a preferred delivery method, the closure device is self-expanding and may be releasably engaged with a percutaneous delivery device. In one embodiment, where the closure device has proximal, intermediate and distal segments, each of the segments is releasably engaged with the delivery device, such as by extending a core or guidewire through eyelets formed in each of the segments of the device. In another embodiment, the closure device may be internally or externally threaded to releasably engage a corresponding delivery device. This threading may be provided at the proximal end of the device, at the distal end of the device, or may be provided in proximal, intermediate and/or distal segments. The closure device may be delivered through an outer deployment catheter which guides the device to the patent foramen ovale.
• In accordance with one embodiment, a closure device for closing a patent foramen ovale is provided. The device includes a proximal segment and a distal segment which may be integrally formed. The device generally has a hook configuration, wherein the distal segment is sized and configured to be positioned over a septum primum of the patent foramen ovale. The proximal segment is sized and configured to extend through the tunnel of the patent foramen ovale, and at its proximal end, may increase in width to form wings to secure the closure device in place. In this configuration, the proximal segment is sized and configured to be positioned along a surface of the septum of the patent foramen ovale in the right atrium. The device may also include a sleeve or laminate structure between the proximal end and the distal segment, the sleeve or laminate structure adapted to be positioned in the patent foramen ovale tunnel. The sleeve or laminate structure is made of material adapted to facilitate cellular in-growth, such as ePTFE.
• In accordance with a further embodiment, a method of closing a patent foramen ovale is provided. The method includes positioning a closure device at a patent foramen ovale and deploying the closure device, such that the septum primum is secured by the closure device. In one embodiment, only the septum primum is secured by the closure device, with the device forming a hook over the tip of the septum primum to hold the septum primum in place. Preferably, the closure device may have wings in a proximal segment thereof that extend beyond the width of the tunnel of the patent foramen ovale. The wings as delivered are positioned in the right atrium against a surface of the septum primum.
• In another embodiment, delivery systems incorporating the devices used in the delivery methods are provided. According to one delivery system, a deployment catheter having a proximal end and a distal end is provided. An actuator extends through the deployment catheter. A closure device is releasably attached to the actuator. The actuator is adapted to advance the closure device from the distal end of the deployment catheter and position a distal segment of the closure device over a septum primum of the patent foramen ovale and position a proximal segment of the closure device over a septum secundum of the patent foramen ovale. The closure device is actuatable to pinch together the septum primum and septum secundum once delivered, and may be self-expanding and/or manually actuated. It will also be appreciated that the closure device can be delivered without the deployment catheter, such that the closure device is releasably secured and released from the actuator to deliver the device.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is an anterior illustration of a heart, with the proximal parts of the great vessels.
• FIG. 2A is a perspective view of a closure device in accordance with one embodiment the present invention.
• FIG. 2B is a perspective view of a closure device in accordance with one embodiment of the present invention in a delivery state.
• FIG. 3 is a side elevational view of the closure device shown inFIG. 2A.
• FIG. 4 is a cross-sectional view of one of the segments of the closure device shown inFIG. 2A.
• FIG. 4A is an enlarged view of a portion of the segment ofFIG. 4.
• FIG. 5 is a cross-sectional view of a patent foramen ovale closed with the closure device ofFIG. 2A, shown schematically.
• FIG. 6 is a perspective view of the closure device ofFIG. 2A in a delivery state.
• FIG. 7 is a perspective view of the closure device ofFIG. 2A during a deployment state.
• FIG. 8 is a schematic cross-sectional view through the heart with a transeptal catheter deployed at a patent foramen ovale.
• FIG. 9 is a cross-sectional view of the catheter ofFIG. 8 through line9-9.
• FIG. 10 is a partial cross-sectional view of an embodiment of the catheter ofFIG. 8, with a closure device being delivered there through.
• FIG. 11A is a partial cross-sectional view of an embodiment of the catheter ofFIG. 8, with an embodiment of a closure device illustrated being delivered using a torque rod.
• FIG. 11B is an enlarged view of a connecting portion of the closure device shown inFIG. 11A.
• FIG. 11C is a partial cross-sectional view of another embodiment of the catheter ofFIG. 8, with another embodiment of a closure device being delivered there through.
• FIG. 11D is an enlarged view of a distal portion of the closure device shown inFIG. 11C.
• FIGS. 12A-E are schematic views of a patent foramen ovale closure procedure in accordance with one embodiment of the present invention.
• FIG. 13 is a perspective view of a closure device in accordance with another embodiment of the present invention.
• FIG. 14 is a perspective view of the closure device ofFIG. 13 in a delivery state.
• FIG. 15 is a back elevational view of a closure device in accordance with another embodiment of the present invention.
• FIG. 16 is a side view of the closure device ofFIG. 15.
• FIG. 17 is a cross-sectional view of a patent foramen ovale closed with the closure device ofFIG. 15.
• FIGS. 18A-E are schematic views of a patent foramen ovale closure procedure in accordance with one embodiment of the present invention.
• FIG. 19A is a front elevational view of a closure device in accordance with another embodiment of the present invention.
• FIG. 19B is a side elevational view of the closure device shown inFIG. 19A.
• FIG. 20 is a cross-sectional view of a patent foramen ovale closed with the closure device ofFIG. 19.
• FIGS. 21A-D are schematic views of a patent foramen ovale closure procedure in accordance with another embodiment of the present invention.
• FIG. 22A is a back view of a closure device in accordance with another embodiment of the present invention.
• FIG. 22B is a back view of a closure device in accordance with another embodiment of the present invention.
• FIG. 22C is a front view of the device ofFIG. 22B, showing a laminated structure attached thereto.
• FIG. 23 is a cross-sectional view of a patent foramen ovale closed with the closure device ofFIG. 22A orFIG. 22B, shown schematically.
• FIGS. 24A-D are schematic views of a patent foramen ovale closure procedure in accordance with one embodiment of the present invention, shown inversely to the deployment orientation to facilitate explanation.
• FIG. 25 is a side elevational view of a closure device in accordance with another embodiment of the present invention.
• FIG. 26 is a side elevational view of the closure device ofFIG. 25 having a plurality of retention structures.
• FIG. 27 is a rear elevational view of the closure device ofFIG. 25.
• FIG. 28 is a partial cross-sectional view of a patent foramen ovale closed with the closure device ofFIG. 25.
• FIG. 29 is a front elevational view of the closure device ofFIG. 25 prior to expansion having a pull wire expansion system.
• FIG. 30 is a front elevational view of the closure device ofFIG. 25 after expansion having a pull wire expansion system.
• FIG. 31 is a front elevational view of the closure device ofFIG. 25 prior to expansion having a twisting expansion system.
• FIG. 32 is a front elevational view of the closure device ofFIG. 25 after expansion having a twisting expansion system.
• FIG. 33 is a schematic side view of a closure device in accordance with another embodiment of the present invention.
• FIG. 34 is an end view of the closure device ofFIG. 33.
• FIG. 35 is a side view of a closure device in accordance with another embodiment of the present invention.
• FIG. 36 is an end view of the closure device ofFIG. 35.
• FIG. 37 is a side view of a closure device in accordance with another embodiment of the present invention.
• FIGS. 38A-B are side schematic views showing the expansion of the closure device ofFIG. 37.
• FIG. 39 is a side view of a closure device in accordance with another embodiment of the present invention.
• FIG. 40 is an end view of the closure device ofFIG. 39.
• FIG. 41 is a side view of the closure device ofFIG. 39 in a collapsed state.
• FIG. 42 is a side view of a closure device in accordance with another embodiment of the present invention.
• FIG. 43 is an end view of the closure device ofFIG. 42.
• FIGS. 44A-C are schematic views of a defect closure procedure in accordance with one embodiment of the present invention.
• FIG. 45 is a side view of the closure device ofFIG. 42 in a collapsed state.
• FIG. 46 is a perspective view of a closure device in accordance with another embodiment of the present invention.
• FIG. 47 is a cross-sectional view of a patent foramen ovale closed with a closure device in accordance with another embodiment of the present invention.
• FIG. 48 is a cross-sectional view of a patent foramen ovale closed with a closure device in accordance with another embodiment of the present invention.
• FIG. 49 is a side elevational view of a closure device in accordance with another embodiment of the present invention.
• FIG. 50 is a front view of the closure device ofFIG. 49.
• FIG. 51 is a cross-sectional view of a patent foramen ovale closed with the closure device ofFIG. 40.
• FIG. 52 is a perspective view of a closure device in accordance with another embodiment of the present invention.
• FIG. 53 is a cross-sectional view of a patent foramen ovale closed with the closure device ofFIG. 52.
• FIG. 54 is a perspective view of a closure device in accordance with another embodiment of the present invention.
• FIG. 55 is an enlarged perspective view of a closure device in accordance with another embodiment of the present invention.
• FIG. 56 is a side view of the closure device ofFIG. 55.
• FIG. 57 is a perspective view of a closure device in accordance with another embodiment of the present invention.
• FIG. 58 is a cross-sectional view of a patent foramen ovale closed with the closure device ofFIG. 57.
• FIGS. 59A-C are schematic views of a defect closure procedure in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• For simplicity, preferred embodiments of the present invention will be described primarily in the context of a patent foramen ovale closure procedure. However, the devices and methods herein are readily applicable to a wider variety of closure or attachment procedures, and all such applications are contemplated by the present inventors. For example, additional heart muscle procedures such as atrial septal defect closure and patent ductus arteriosis closure are contemplated. Vascular procedures such as isolation or repair of aneurysms, anastomosis of vessel to vessel or vessel to prosthetic tubular graft joints may also be accomplished using the devices of the embodiments described herein. Attachment of implantable prostheses, such as attachment of the annulus of a prosthetic tissue or mechanical heart valve may be accomplished. A variety of other tissue openings, lumens, hollow organs and surgically created passageways may be closed. Adaptation of the devices and methods disclosed herein to accomplish procedures such as the foregoing will be apparent to those of skill in the art in view of the disclosure herein.
• Referring toFIG. 1, aheart100 is illustrated to show certain portions including theleft ventricle102, theleft atrium104, the leftatrial appendage106, thepulmonary artery108, theaorta110, theright ventricle112, theright atrium114, and the rightatrial appendage116. As is understood in the art, theleft atrium104 is located above theleft ventricle102 and the two are separate by the mitral valve (not illustrated).
• First Clip Embodiments
• Referring to FIGS.2A and3-7, there is illustrated one embodiment of an occlusion orclosure device200 sized and configured to close a patent foramen ovale in accordance with one embodiment of the present invention. The closure device preferably comprises a wire shaped to form a clip, which is preferably shaped like a paperclip. As illustrated, in one embodiment the closure device can be considered to have generally an S-shape or two adjacent U-shaped or clip portions, as described further below. Theclosure device200 has aproximal end202 and adistal end204. The designation proximal or distal is not intended to indicate any particular anatomical orientation or deployment orientation within the deployment catheter, as described below.
• Theclosure device200 generally has three sections: aproximal segment206, adistal segment208, and anintermediate segment210. As illustrated inFIG. 4, each of these segments is preferably generally annular-shaped or oval-shaped forming a loop, and may be generally parallel to each other when thedevice200 is in its deployment state, shown inFIG. 2A. It will be appreciated that the segments may have any suitable size and configuration for closing a patent foramen ovale, including round, oblong, rectangular, triangular and square. Each of thesegments206,208,210 may be formed fromwire212 and may be separately or integrally formed.
• In one embodiment, the threesegments206,208,210 are sequentially aligned such that adistal end206bofproximal segment206 is connected to aproximal end210aofintermediate segment210, and adistal end210bofintermediate segment210 is connected to aproximal end208aofdistal segment208. As illustrated, thesesegments206,208,210 are connected by connectingportions211aand211b, and may be integrally formed with the connecting portions. Alternatively, they may be joined together by any suitable technique. Theclosure device200 is also preferably provided with adetachment element214 at itsproximal end202, illustrated as an externally threaded portion. Alternatively, theproximal end202 of thedevice200 may be provided with a threaded aperture through which a delivery core is threadably engaged, a loop or eyelet, or other suitable structure as will be discussed herein for releasably connecting the device to a deployment system.
• In one embodiment, awire212 is used to form thesegments206,208 and210, as well as connecting portions211, and comprises a metal such as stainless steel, Nitinol, Elgiloy, or others which can be determined through routine experimentation by those of skill in the art. The wire may also be biodegradable. Wires having a circular or rectangular cross-section may be utilized depending upon the manufacturing technique. It will be appreciated that theclosure device200 need not be formed from a wire, and can be an integral structure, for example, laser cut from a tube or other stock. It is also envisioned that other non-metallic biocompatible materials may be used to formwire212. Thewire212 may be solid or hollow.
• As shown inFIG. 4A, in one embodiment at least a portion of thewire212 is covered with asleeve224. Thesleeve224 may comprise any of a variety of materials which facilitate cellular in-growth, such as ePTFE. The suitability of alternate materials forsleeve224 can be determined through routine experimentation by those of skill in the art. Thesleeve224 may be provided on either one or all sections of the closure device. For example, theintermediate segment210 alone or theentire device200 may be provided withsleeve224. In one embodiment, thesleeve224 comprises two layers. The two layers may be bonded to each other around thewire212 in any of a variety of ways, such as by heat bonding with or without an intermediate bonding layer such as polyethylene or FEP, adhesives, sutures, and other techniques which will be apparent to those of skill in the art in view of the disclosure herein. Thesleeve224 in one embodiment preferably is securely attached to thedevice200 and retains a sufficient porosity to facilitate cellular ingrowth and/or attachment.
• Referring back toFIG. 2A, thedevice200 is illustrated in its deployment state. Thedevice200 may be self-expanding, having a remembered shape as illustrated inFIG. 2A. Alternatively, thedevice200 may be mechanically actuated to assume its deployment state. As illustrated, thedevice200 preferably includes alocking element228 and retention elements, preferably in the form ofeyelets230, for retaining thelocking element228 to theclosure device200. In one embodiment, theeyelets230 are offset from one another on adjacent segments of the device. In another embodiment, theeyelets230 are in line with the longitudinal axis of thedevice200. Other details regarding a device having eyelets described above, as well as similar devices, may be found in U.S. Pat. Nos. 6,214,029, 6,551,344 and 6,440,152, which are hereby incorporated by reference in its entirety. The lockingelement228 is used to longitudinally shorten and radially expand the device. The lockingelement228 preferably comprises a locking string which is preferably used to both longitudinally shorten and radially expand and lock the device at the patent foramen ovale. Other details regarding the locking element described above as well as similar devices may be found in U.S. Pat. No. 5,861,003, which is hereby incorporated by reference in its entirety. Preferably, upon deployment and positioning of thedevice200, the lockingelement228 secures the locking string to retain thedevice200 is the deployed position. The locking string may also be drawn proximally to increase the clamping force of thedevice200 on the septa of the patent foramen ovale. It will be appreciated that thedevice200 may still be self-expanding, with the locking string also mechanically actuating thedevice200.
• In some embodiments, thedevice200 may be made by laser cutting flat stock sheet. In another embodiment, thedevice200 and theeyelets230 may comprise a metal wire such as stainless steel, Nitinol, Elgiloy, or others which can be determined through routine experimentation by those of skill in the art.
• FIG. 2B illustrates an alternative embodiment of a self-expanding closure device including at least one eyelet, and more preferably, a plurality ofeyelets230 to assist with collapse ofdevice200 into a delivery device. Thedevice200 may have aproximal segment206, anintermediate segment210, and adistal segment208 like the embodiment ofFIG. 2A, and preferably is formed from a single wire forming three similar shaped segments, which may be generally looped or oval in shape. Theeyelets230 are integrally formed by small loops made in the wire, preferably at theproximal end202,distal end204, and at connectingportions211aand211b. In one embodiment, theeyelets230 are configured to receive an actuator orcore259, such as hypotubing, solid wire or a guidewire, to releasably secure thedevice200 and stress the wire in a longitudinally stretched position during deployment as shown inFIG. 2B. Upon confirmation of optimal positioning in the patent foramen ovale or other structure, the core may be retracted proximally, thereby releasing thesegments208,210 and206. Further details regarding the delivery of this device are described below.
• For use in a patent foramen ovale, thesegments206,208,210 of thedevice200 in one embodiment has an expanded diameter within the range of from about 1 cm to about 5 cm, and, in a further embodiment, about 2.5 cm. When thedevice200 is longitudinally stretched, the overall length from thedistal end204 to theproximal end202 is preferably within the range of about 4 cm to about 20 cm and, in one embodiment, about 8 cm. Preferably thewire212 has a diameter of 0.001-0.03 in.
• Although thedevice200 is shown having a paperclip-like shape, it is envisioned that a number of variations of this shape can be utilized to provide the same results. For example, a bend may be provided in the device to aid in closure. For example, a bend may be placed in theintermediate segment210, such that thedevice200 is sized and configured to conform to the shape of the patent foramen ovale. Also, other non-circular or round shapes may be used for each segment, rather than the annular shape, as discussed above.
• FIG. 5 illustrates theclosure device200 implanted in apatent foramen ovale120, Thepatent foramen ovale120 includes aseptum primum116 having asurface126 adjacent theleft atrium104, and aseptum secundum118 having asurface124 adjacent theright atrium114. A tunnel orchannel122 is located between the septum primum116 andseptum secundum118. Theclosure device200 may be delivered to thepatent foramen ovale120 using any suitable technique, such as described below. Once positioned, thedistal segment208 is positioned over thetip130 of the septum primum116 and lies along thesurface126 of theseptum primum116 adjacent theleft atrium104. Theintermediate segment210 lies between the septum primum116 andseptum secundum118 inchannel122. Theproximal segment206 is positioned over thetip128 of theseptum secundum118 and lies along thesurface124 of theseptum secundum118 adjacent theright atrium114. After being delivered, theclosure device200 exerts a force on the septum primum116 andseptum secundum118 to draw the two closer together, either through mechanical actuation or self-expansion of the device. In one embodiment, the proximal and distal segments are identical in shape, and may have identical shapes that form mirror images of each other across the patent foramen ovale to equally apply compressive force to both sides of the patent foramen ovale.
• In one embodiment, theclosure device200 is designed to be implanted using a deployment catheter, such as described with respect toFIGS. 8-12 below. As shown inFIG. 6, thedevice200 is designed to remain in a delivery or elongated state while in the catheter (not shown). In this delivery state, thedevice200 can assume a generally elongate configuration wherein theproximal end202 anddistal end204 are pulled apart from each other in a generally linear manner. Upon delivery to the patent foramen ovale, thedevice200 is radially expanded (FIG. 7) into a clip or generally S-shaped configuration to occlude or close the patent foramen ovale. As illustrated, when expanded, the proximal anddistal segments202,204 of the device are drawn relatively closer to the intermediate segment. In one embodiment, the device is preferably attached viadetachment element214 to a delivery device such as an actuator prior to deployment, and is then detached atdetachment element214 when properly positioned. In a further embodiment, thedetachment element214 may use a tether line in addition to or instead of a threaded fitting. Tether lines are described in detail in U.S. Pat. Nos. 6,214,029, 6,440,152, and 6,551,344, which are incorporated in their entirety herein. The procedure for placing the closure device and delivery device will be described in further detail hereinafter.
• As shown inFIGS. 8-11, a closure device deployment system is provided for delivery of a closure device to a patent foramen ovale. Referring toFIG. 8, a closuredevice deployment system240 comprises generally acatheter242 for placing adetachable closure device200 within a body cavity or lumen. Thecatheter242 comprises an elongate flexibletubular body246, extending between aproximal end248 and adistal end250. The catheter is shown in highly schematic form, for the purpose of illustrating the functional aspects thereof. The catheter body will have a sufficient length and diameter to permit percutaneous entry into the vascular system, and transluminal advancement through the vascular system to the desired deployment site. For example, in an embodiment intended for access at the femoral artery and deployment within the patent foramen ovale, thecatheter242 will have a length within the range of from about 50 cm to about 150 cm, and a diameter of generally no more than about 15 French. Further dimensions and physical characteristics of catheters for navigation to particular sites within the body are well understood in the art and will not be further described herein.
• The flexible body can be manufactured in accordance with any of a variety of known techniques. In one embodiment, theflexible body246 is extruded from any of a variety of materials such as HDPE, PEBAX, nylon, polyimide, and PEEK. Alternatively, at least a portion or all of the length of the tubular body may comprise a spring coil, solid walled hypodermic needle or other metal tubing, or braided reinforced wall, as are known in the art.
• Thetubular body246 is further provided with ahandle252 generally on theproximal end248 of thecatheter242. Thehandle252 may be provided with a plurality of access ports. Generally, handle252 is provided with an access port which may be used as a guidewire port in an over the wire embodiment, and a deployment wire or actuator port. Additional access ports such as a contrast media introduction port, or others may be provided as needed, depending upon the functional requirements of the catheter. Thehandle252 permits manipulation of the various aspects of the closuredevice deployment system240, as will be discussed below. Handle252 may be manufactured in any of a variety of ways, typically by injection molding or otherwise forming a handpiece for single-hand operation, using materials and construction techniques well known in the medical device arts.
• Anactuator244, as described below, is provided in accordance with one embodiment of the present invention, used to releasably engage and deploy theclosure device200. Any of a variety of structures such as solid cores, polymeric or metal single or multiple strand wires, ribbons, or tubes can be used. Theactuator244 may be retracted as with a pullwire design, or rotated as with a torque rod design, as will be discussed herein. Theactuator244 may be hollow or solid.
• In use, the deployment catheter is percutaneously introduced into the vascular system and transluminally advanced into the heart and, subsequently, to the patent foramen ovale using techniques which are known in the art.
• The patent foramen ovale may be accessed via catheter through a variety of pathways. It may be accessed from the arterial circuit. The catheter is introduced into the arterial vascular system, preferably in the femoral artery, and guided up the descending thoracic and/or abdominal aorta. The catheter may then be advanced into the left ventricle through the aortic outflow tract. Once in the left ventricle, the catheter may be directed up through the mitral valve and into the left atrium. When the catheter is in the left atrium, it may be directed into the patent foramen ovale and the closure device deployed.
• Alternatively, the patent foramen ovale may be accessed from the venous circuit. The catheter may be introduced into the venous system, preferably in the femoral vein, advanced into the inferior vena cava or superior vena cava and guided into the right atrium. The catheter may then be directed to the patent foramen ovale. Alternatively, once in the right atrium, the catheter may be advanced through the tricuspid valve and into the right ventricle and directed to the ventricular septal defect and the closure device deployed.
• As shown inFIG. 10, in a preferred construction, acatheter242 having a single lumen is illustrated. Also shown is an actuator244 that acts as the actuator for deploying thedevice200. In the illustrated embodiment, the actuator may be an elongate body such as a core wire that extends to thehandle252, and more preferably may be hollow to provide a passageway for thelocking element228 described with respect toFIG. 2B above. Theactuator244 may be removably attached to theproximal end202 or other point of attachment on theclosure device200, such as through a threaded attachment atdetachment element214. Proximal retraction of theactuator244 while resisting proximal motion of theclosure device200 or distally pulling on the closure device will cause elongating of theclosure device200 into its delivery state, as has been discussed. Theclosure device200 is preferably loaded into thedeployment catheter242 as shown inFIG. 10. Theactuator244 may be locked or removably attached with respect to theclosure device200, and later severed or otherwise detached to enable removal of thedeployment catheter242 and proximal retraction of theactuator244. In addition to a threaded connection, locking of theactuator244 with respect to theclosure device200 may be accomplished in any of a variety of ways. For example, depending upon the desired catheter design, locking may be accomplished by using interference fit or friction fit structures, tether line, adhesives, a knot, or other technique known to one of ordinary skill in the art.
• In the embodiment illustrated inFIG. 10, theactuator244 is releasably connected to the proximal end of theclosure device200. This permits distal advancement of theclosure device200 through thecatheter242 by distal movement of theactuator244. The proximal end of theactuator244 may be connected to any of a variety of controls, including rotational knobs, levers and slider switches, depending upon the design preference. To deploy thedevice200, the actuator is pushed distally untilclosure device200 exits thecatheter242. Upon exiting the catheter, the locking element as described above may be actuated to cause the device to move to its deployed configuration. Alternatively, thedevice200 may self-expand as it exits the catheter. After positioning of the device is confirmed, theactuator244 is released from thedevice200, and the actuator and deployment catheter are removed. Where a locking element is used, this locking element may be cut, released or otherwise secured to fix the position of the closure device. Further details on delivery methods are described below with respect toFIGS. 12A-12E.
• When delivering a device such as in the embodiment ofFIG. 2B, in another embodiment, adetachment element214 may be provided that comprises a threaded attachment located on thedistal segment208. In this embodiment, thecore wire259 is inserted through theeyelets230 of theclosure device200 and is distally threaded to connect with the detachment element, causing elongation of thedevice200 into its delivery state. Theclosure device200 is inserted into thedeployment catheter242 with the core wire inserted through theeyelets230 of thedevice200 and attached at thedistal segment208. The core wire may be advanced out of the deployment catheter to position the closure device in the patent foramen ovale, as discussed below. The core wire may then be detached from thedistal segment208 and retracted proximally to deploy thedevice200. A hollow push rod positioned proximal to the closure device and over thecore wire259 may be used to assist in releasing the closure device from the core wire. Alternatively, the closure device may be positioned distally beyond the distal end of thedeployment catheter242, and interference between thedeployment catheter242 and theclosure device200 may be used to assist in releasing the closure device from the core wire. As discussed, thedetachment element214 may alternatively comprise a tether line, a threaded fitting, or other technique as is known to one of ordinary skill in the art to releasably secure theclosure device200 to thecore wire259. It will also be appreciated that in the embodiment ofFIG. 2B, no detachment element may even be necessary other than theeyelets230 that secure theclosure device200 to thecore wire259. As the core wire is retracted proximally from theeyelets230 in thesegments206,208,210, thedevice200 is released to its deployed shape, securing thesepta116,118 of the patent foramen ovale, as described further below.
• Theactuator244 orcore wire259 in one embodiment extends axially throughout the length of thecatheter body246, and is attached at its proximal end to a control on thehandle252. Theactuator244 orcore wire259 may comprise any of a variety of structures which has sufficient lateral flexibility to permit navigation of the vascular system, and sufficient axial column strength to be pushed through thecatheter242. Any of a variety of structures such as hypotube, solid core wire, “bottomed out” coil spring structures, or combinations thereof may be used, depending upon the desired performance of the finished device. In one embodiment, the core wire comprises stainless steel tubing.
• As used herein, the term “core wire” is intended to include any of a wide variety of structures which are capable of transmitting axial tension or compression such as a pushing or pulling force with or without rotation from theproximal end248 to thedistal end250 of thecatheter242. Thus, monofilament or multifilament metal or polymeric rods or wires, woven or braided structures may be utilized. Alternatively, tubular elements such as a concentric tube positioned within the outertubular body246 may also be used as will be apparent to those of skill in the art.
• FIGS. 11A-11D illustrate an alternate construction wherein a closure device is biased toward its deployment configuration, such as being made from a shape memory material, and may be radially enlarged or reduced by rotating a torque element extending through the deployment catheter. Referring toFIGS. 11A and 11C, arotatable torque rod260 extends axially through thedeployment catheter242, and also extends through theclosure device200, preferably through at least one internally threaded portion provided in theclosure device200. For example, as shown inFIG. 11B, an externally threadedportion262 oftorque rod260 may engage an internally threaded portion within connectingsegment211a. The rotatable torque rod may be encased in a plurality of tubes (not shown) within the closure device that are positioned approximately diametrically within any or all ofsegments206,208, and210, said tubes preferably attached to the segments at each end of each tube. These tubes serve to guide the torque rod from the proximal end of the device through the connecting segments to the distal end. The proximal end of thetorque rod260 may be connected at a proximal manifold to a manual rotation device such as a hand crank, thumb wheel, rotatable knob or the like. Alternatively, thetorque rod260 may be connected to a power driven source of rotational energy such as a motor drive or air turbine.
• The terms torque rod or torque element are intended to include any of a wide variety of structures which are capable of transmitting a rotational torque throughout the length of a catheter body. For example, solid core elements such as stainless steel, nitinol or other nickel titanium alloys, or polymeric materials may be utilized. In an embodiment intended for implantation over a guidewire, thetorque rod260 is preferably provided with an axially extending central guidewire lumen. This may be accomplished by constructing thetorque rod260 from a section of hypodermic needle tubing, having an inside diameter of from about 0.001 inches to about 0.005 inches or more greater than the outside diameter of the intended guidewire.Tubular torque rods260 may also be fabricated or constructed utilizing any of a wide variety of polymeric constructions which include woven or braided reinforcing layers in the wall. Torque transmitting tubes and their methods of construction are well understood in the intracranial access and rotational atherectomy catheter arts, among others, and are not described in greater detail herein.
• One or more distal portions of the torque rod may be threaded as shown inFIGS. 11B and 11D. More particularly, threadedportions262 may be provided ontorque rod260, to correspond to internally threaded portions of the distal segment208 (FIG. 11D) or the connectingportions211aand211b(FIG. 11B). A distal threaded portion or distal rotating coupler, not shown, may be provided at thedistal end204 of the device to receive the distal end of the torque rod. As will be appreciated by those of skill in the art in view of the disclosure herein, in one embodiment, rotation of thetorque rod260 in a first direction relative to theclosure device200 will cause thetorque rod260 to advance distally. This distal advancement will stress the device and result in an axial elongation and radial reduction of theclosure device200 as thetorque rod260 is advanced distally into the threaded apertures of theclosure device200. Rotation of thetorque rod260 in a reverse direction will cause a proximal retraction of thetorque rod260, thus enabling a radial enlargement and axial shortening of theclosure device200.
• In another embodiment, similar to that described with respect toFIG. 2B above where only thedistal end204 of thedevice200 is threaded, the torque rod may be inserted througheyelets230 formed at theproximal end202 and connectingsegments211aand211bof the device, thereby axially elongating thedevice200, and threadingly engaging thedistal end204. Disengaging thetorque rod260 from thedistal segment208 will release thesegment208, permitting thesegment208 to collapse in its deployed position. The remainingsegments206,210 may be released by proximally retracting thetorque rod260 from theeyelets230 corresponding to eachsegment206,210.
• With thetorque rod260 threadingly engaging thedevice200, upon placement of theclosure device200 at the desired implantation site, thetorque rod260 is rotated in a direction that produces an axial proximal retraction. This allows radial enlargement of the radially outwardlybiased closure device200 at the implantation site. Continued rotation of thetorque rod260 will cause the threaded portion to exit proximally through the one or more threaded apertures provided on theclosure device200.
• With thetorque rod260 extending through thedeployment catheter242, thedevice200 may be provided beyond the distal end of thedeployment catheter242, so that when the torque rod is rotated to move the torque rod proximally, the distal force applied by the deployment catheter on thedevice200 allows the device to release the torque rod. Thedeployment catheter242 may also be provided with an antirotation lock (not shown) between a distal end of thecatheter242 and theclosure device200. In general, the rotational lock may be conveniently provided by cooperation between a first surface on the distal end of thedeployment catheter242, which engages a second surface on theclosure device200, to rotationally link thedeployment catheter242 and theclosure device200. Any of a variety of complementary surface structures may be provided, such as an axial extension on one of the first and second surfaces for coupling with a corresponding recess on the other of the first and second surfaces. Such extensions and recesses may be positioned laterally offset from the axis of the catheter. Alternatively, they may be provided on the longitudinal axis with any of a variety of axially releasable anti-rotational couplings having at least one flat such as a hexagonal or other multifaceted cross sectional configuration.
• Any other means known may be used for temporarily attaching the closure device to a delivery system such as a deployment catheter or actuator. For example, any of a variety of interference fit such as threaded fit or snap fit, pin/loop combinations, interfering diameters, or heat dissociable solders or polymer bonds may be utilized.
• The closuredevice deployment system240 thus permits theclosure device200 to be maintained in a low crossing profile configuration, to enable transluminal navigation to a deployment site. Following positioning at or about the desired deployment site, distal advancement or proximal retraction of an actuator enables theclosure device200 to radially enlarge. Radial enlargement in one embodiment occurs under the device's own bias. Alternatively, certain embodiments of the closure device can be enlarged under positive force, such as by inflation of a balloon or by a mechanical mechanism as is discussed elsewhere herein. Once the clinician is satisfied with the position of theclosure device200, such as by injection of dye and visualization using conventional techniques, the actuator is proximally retracted thereby enabling detachment of theclosure device200 from thedeployment system240.
• If, however, visualization reveals that theclosure device200 is not at the location desired by the clinician, theclosure device200 can be radially reduced and axially elongated, thereby enabling repositioning of theclosure device200 at the desired site. In the embodiment ofFIG. 10, this repositioning is allowed by pulling theclosure device200 partially or wholly back into the catheter before release of the detachment element. In the embodiment ofFIGS. 11A-D, the torque rod can be distally advanced to reengage the internal threading of the closure device. In some embodiments the torque rod will be guided within tubes attached to the segments (discussed previously). Thus, theclosure device200 can be enlarged or reduced by the clinician to permit repositioning and/or removal of theclosure device200 as may be desired.
• With reference toFIGS. 12A-12E, a closure device200 (shown schematically) is preferably positioned within a patent foramen ovale. Initially, thedevice200 is collapsed inside adeployment catheter242. Thecatheter242 is then positioned at or near thepatent foramen ovale120, as shown inFIG. 12A, more preferably through thechannel122 between the septum primum and septum secundum. Then, as shown inFIG. 12B, thedistal segment208 of the device is exposed and is pushed out, preferably using an actuator as described above, and deployed over theseptum primum116. The deployment catheter is retracted while releasing theintermediate segment210 to be positioned inside the patent foramen ovale channel122 (shown inFIG. 12C), along a surface of the septum primum and the septum secundum. Lastly, theproximal segment206 is released from the deployment catheter and positioned against the septum secundum118 (FIG. 12D). The positioning of each of the segments relative to the septum primum and septum secundum can occur due to a natural bias of the device as it exits the catheter, due to a mechanical actuation of the distal segment into this position, as described above, or due to a combination of natural bias and mechanical actuation. In another embodiment, a core may hold eachsegment206,208,210 in a delivery or elongated state until proper positioning may be confirmed. The core may then be retracted, releasing thedevice200 for deployment.
• After optimal positioning and closure is achieved, thedevice200 can then be detached from the delivery system, as shown inFIG. 12E. In one embodiment,detachment element214 comprises a flexible segment such as a hinge or braid to allow thedevice200 to assume a final implanted attitude without undue distortion applied to the implant or the septa from the deployment catheter. Thedevice200 can also be captured and retrieved at any time during the procedure as long as it is not fully detached from the delivery system. Once in position, the device clips the patent foramen ovale closed by exerting a force on the septum primum and septum secundum to draw the two together.
• With reference toFIGS. 13-14, an alternative embodiment of a closure device in accordance with the present invention is shown. Theclosure device300 preferably is shaped to form a clip-like device, similar to the closure device ofFIG. 2A. The closure device has aproximal end302 and adistal end304. The closure device generally has three sections: aproximal segment306, adistal segment308, and anintermediate segment310. In contrast to the device shown inFIG. 2A, in theclosure device300 shown inFIG. 13, theintermediate segment310 is preferably a single straight wire preferably covered in asleeve324, rather than an elongated annular wire or loop. Theintermediate segment310 may also be cut from flat stock sheet. Both the proximal anddistal segments306,308 are generally annular in shape as described above. Thesegments306,308,310 are formed from awire312 and are connected by connectingportions311aand311b, similar to the embodiment discussed above. Thesegments306,308,310 form an integral structure for closing or occluding a patent foramen ovale. Theclosure device300 is also preferably provided with adetachment element314 on proximal end, as discussed above.
• When delivered, theintermediate segment310 is positioned in the channel between the septum primum116 and theseptum secundum118 to close thepatent foramen ovale120, as was described in the embodiment above. Thedistal segment308 is preferably positioned in the left atrium, while theproximal segment306 is positioned in the right atrium. Theclosure device300 is designed to be implanted using a delivery system, such as described above, and may have a collapsed or delivery state, as shown inFIG. 14.
• Preferably, thewire312 comprises a metal such as stainless steel, Nitinol, Elgiloy, or others which can be determined through routine experimentation by those of skill in the art. The wire may also be biodegradable. Wires having a circular or rectangular cross-section may be utilized depending upon the manufacturing technique. In one embodiment, a circular cross section wire is cut such as by known laser cutting techniques from tube stock. The closure device is preferably an integral structure, such as a single ribbon or wire, or element cut from a tube stock.
• Theintermediate segment310 is preferably covered with asleeve324. The wire of the proximal anddistal segments306,308 may also be covered with a sleeve. Thesleeve324 may comprise any of a variety of materials which facilitate cellular in-growth, such as ePTFE. The suitability of alternate materials forsleeve324 can be determined through routine experimentation by those of skill in the art. In one embodiment, thesleeve324 comprises two layers. The two layers may be bonded to each other around thewire312 in any of a variety of ways, such as by heat bonding with or without an intermediate bonding layer such as polyethylene or FEP, adhesives, sutures, and other techniques which will be apparent to those of skill in the art in view of the disclosure herein. Thesleeve324 in one embodiment preferably is securely attached to thedevice300 and retains a sufficient porosity to facilitate cellular ingrowth and/or attachment. In one embodiment, thesegments324,310 may be configured to occlude thechannel122 in addition to the closure of the patent foramen ovale induced by the proximal anddistal segments306,308.
• Preferably, thedevice300 includes alocking element328 andretention elements330 for retaining thelocking element328 to theclosure device300, as described above. The lockingelement328 is used to longitudinally collapse the device and hold it in place at the patent foramen ovale. The lockingelement328 preferably comprises a locking string which is preferably used to both expand and lock the device at thepatent foramen ovale120.
• For use in a patent foramen ovale, theclosure device300 has an expanded diameter within the range of from about 1 cm to about 5 cm, and, in one embodiment, about 2.5 cm. The overall length of theclosure device300 from thedistal end308 to theproximal end306 is preferably within the range of from about 4 cm to about 20 cm and, in one embodiment, about 8 cm. Preferably the wire has a diameter of 0.001-0.03 in.
• Single Clip or Hook Embodiment
• With reference toFIGS. 15-17, there is illustrated an additional embodiment of aclosure device400. The device comprises a proximal or ananterior section402 and a distal orposterior section404. Afirst axis406 passing through theanterior section402, and asecond axis408 passing through theposterior section404, generally parallel to one another, are shown. Theanterior section402 compriseswings409, which are used to anchor the device into the correct atrium, preferably the right atrium. Thewings409 preferably extend to beyond the edges of the patent foramen ovale to provide additional support todevice400. The anterior andposterior sections402,404 are integral and form a structure which hooks over thetip130 of theseptum primum116. The device is provided with aloop410 integral with the structure to attach thedevice400 to the delivery device. Theanterior section402,posterior section404, andloop410 are an integral structure and are formed of asingle wire412. The device is preferably shaped like a hook, as can be seen with reference toFIG. 16, and is preferably self-expanding into the hook shape.
• Theanterior section402 andposterior section404 are positioned between the septum primum116 and theseptum secundum118 and hook over the septum primum116 to close apatent foramen ovale120, as shown inFIG. 17. This embodiment stabilizes the flap of thepatent foramen ovale120. Theposterior section404 is positioned in the left atrium, while theanterior section402 is positioned in the patent foramen ovale and extends out into the right atrium. Theanterior section402 is preferably of such a length as to extend along the septum primum116 to prevent the septum primum116 from displacing into theleft atrium104. Theposterior section404 prevents thetip130 of the septum primum116 from displacing into theleft atrium104 while theanterior section402 secures thedevice400 to theseptum primum116. Theanterior section402 is preferably sized and configured to extend along theright atrium114 side of the septum primum116 such that the base of theseptum primum116 provides support to thedevice400, which prevents displacement of theseptum primum tip130 into theleft atrium104.
• Preferably, thewire412 comprises a metal such as stainless steel, Nitinol, Elgiloy, or others which can be determined through routine experimentation by those of skill in the art. The wire may also be biodegradable. Wires having a circular or rectangular cross-section may be utilized depending upon the manufacturing technique. In one embodiment, a circular cross section wire is cut such as by known laser cutting techniques from tube stock. The closure device is preferably an integral structure, such as a single ribbon or wire, or element cut from a tube stock.
• A portion of thedevice400 is preferably covered with asleeve424 as shown inFIG. 16. Thesleeve424 bridges the fossa andpatent foramen ovale120, while the wire structure stabilizes the flap of thepatent foramen ovale120. Thesleeve424 may comprise any of a variety of materials which facilitate cellular in-growth, such as ePTFE. The suitability of alternate materials forsleeve424 can be determined through routine experimentation by those of skill in the art. In one embodiment, thesleeve424 comprises two layers. The two layers may be bonded to each other around thewire412 in any of a variety of ways, such as by heat bonding with or without an intermediate bonding layer such as polyethylene or FEP, adhesives, sutures, and other techniques which will be apparent to those of skill in the art in view of the disclosure herein. Thesleeve424 in one embodiment preferably is securely attached to thedevice400 and retains a sufficient porosity to facilitate cellular ingrowth and/or attachment.
• Referring toFIGS. 18A-E, aclosure device400 such as described above is preferably positioned within a patent foramen ovale to be closed or occluded. In a patent foramen ovale application, the distal end of adeployment catheter242 is positioned at or near thepatent foramen ovale120, as shown inFIG. 18A. The position may be confirmed using fluoroscopy, echocardiography, or other imaging. Thedevice400 is initially in a collapsed state withincatheter242, such as described above. Theleft atrium segment404 of thedevice400 is exposed and positioned on theseptum primum116 by advancing or rotating actuator244 (not shown), as discussed herein. SeeFIG. 18B. Theanterior segment402 is then positioned inside the patentforamen ovale channel122 and on theseptum secundum118 again by advancing or rotating actuator244 (not shown) (FIG. 18C). One of ordinary skill in the art will recognize that actuation of thedevice400 may be accomplished as mentioned above. For example, actuation of thedevice400 may be mechanically induced, self-expanding, a combination of mechanical and self-expanding. Additionally, deployment and detachment of the device may be accomplished as discussed above. For example, the device may be deployed via a tether line or torque rod, and detached accordingly as discussed previously. In one embodiment, a tether line, core wire orother actuator244 may be attached toloop410 for releasably deploying the device.
• After optimal positioning and sealing is achieved, as shown inFIG. 18D, thedevice400 can then be detached from the delivery system, as shown inFIG. 18E. Thedevice400 can also be captured and retrieved at any time during the procedure as long as it is not detached from theactuator244.
• Other Clip Embodiments
• Referring toFIGS. 19-20, there is illustrated another preferred embodiment of the present invention. Theclosure device440 comprises a proximal or ananterior section442, a distal orposterior section444 and anintermediate section446. Theposterior section444 comprises twolegs449 that extend generally parallel to a longitudinal axis of the device which form an exaggerated “T” shape with theintermediate section446. Theanterior section442 has a generally rectangular shape.Sections442,444, and446 may be self-expanding and form an integral structure452, or may be separately joined such as by a hinged connection. In some embodiments, anchors447 may be provided to secure the implant against the septum primum116 andseptum secundum118. As illustrated, the anchors may be punched in the anterior andintermediate section442 and446 and heat set or deformed to extend proud ofdevice440 surface.Hole448 may be provided in proximal end ofanterior section442 to facilitate attachment of a tether and the like toclosure device440.
• Theanterior section442 is configured and positioned in the right atrium, theposterior section444 is configured to be positioned in the left atrium, and theintermediate section446 is configured to be positioned between the septum primum116 and theseptum secundum118. Theposterior section444 hooks over the septum primum116 and theanterior section442 hooks over theseptum secundum118 to occlude or close apatent foramen ovale120, as shown inFIG. 20. The septum primum116 andseptum secundum118 are held together by the clamping force exerted by the clips defined betweensections444 and446, andsections442 and446. The design minimizes the amount of material exposed to blood flow in the left and right atria, thereby reducing the chance of clot formation. The shape is designed to fit the anatomy without distending tissue, thereby reducing the chance of leaks and promoting health.
• In some embodiments, the clip structure can be made by laser cutting flat stock sheet. Preferably, the clip structure comprises a metal such as stainless steel, Nitinol, Elgiloy, or others which can be determined through routine experimentation by those of skill in the art.
• Referring toFIG. 21A, aclosure device440 is preferably delivered to a defect to be occluded, such as a patent foramen ovale. In a patent foramen ovale application, the distal end of thedeployment catheter242 is positioned at or near thepatent foramen ovale120, as shown inFIG. 21A. The position may be confirmed using fluoroscopy, echocardiography, or other imaging. Thedevice440 is initially in a collapsed state withincatheter242. Thedevice440 may be releasably attached to anactuator244, which may be a push rod. The distal end of thedeployment catheter242 is advanced between the septum primum116 andseptum secundum118 as shown inFIG. 21B. Theposterior portion444 is advanced out of the distal end of thedeployment catheter242 and over theseptum primum116, as shown inFIG. 21C, preferably by withdrawing thecatheter242 proximally. As thecatheter242 is withdrawn, theposterior portion444 flips over into theleft atrium104 and hooks over theseptum primum116. Theintermediate section446 andanterior sections442 are then delivered, as shown inFIG. 21D, by further withdrawing thecatheter242 untilanterior section442 flips over the septum secundum188. After optimal positioning and sealing is achieved, as shown inFIG. 21D, thedevice440 can then be detached from the actuator ortether line260 anddeployment catheter242. Thedevice440 can also be captured and retrieved at any time during the procedure as long as it is not detached from the actuator.
• In one embodiment, thedevice440, and more particularly theanterior portion442, has a length L of about 1 inch, thickness t of about 0.02″, and a width W of about 0.475″. The length and width of the anterior portion are preferably greater than the length and width of the posterior portion. More preferably, the anterior portion may be approximately twice as long or greater than the posterior portion, and about 25% or more wider than the posterior portion.
• With reference toFIGS. 22A-C and23, there is illustrated another preferred embodiment of the present invention. Thedevice470 is preferably made from a single wire structure, and comprises a proximal or ananterior section472, a distal orposterior section474, and anintermediate section476. Theposterior section474 compriseswings479 which are used to anchor the device into the left atrium. Theintermediate section476 may include crossed wire portions as shown inFIG. 22A or non-crossed wire portions as shown inFIG. 22B. The anterior section may be hexagonal in shape. The anterior, posterior, andintermediate sections472,474,476 are integral and form a structure which hooks over the septum primum and the septum secundum. The device may be provided with at least oneloop480 at a proximal end of the device integral with the structure. Asecond loop481 may be provided at the intersection of the anterior and intermediate sections. As shown inFIG. 22B, thedevice470 may also comprise athird loop484 at the distal end of theposterior section474. The function of thefirst loop480,second loop481, andthird loop484 will be discussed below with reference to loading and deployment of thedevice470. Theanterior section472,posterior section474,intermediate section476 and at least oneloop480 are preferably an integral structure and are formed of asingle wire482. The device is preferably shaped like a clip, as can be seen with reference toFIG. 23, when the device is deployed.
• As shown inFIG. 23, theanterior section472 is positioned in the right atrium, theposterior section474 is positioned in the left atrium, and theintermediate section476 is positioned between the septum primum116 and theseptum secundum118. Theposterior section474 hooks over the septum primum116 and theanterior section472 hooks over theseptum secundum118 to occlude apatent foramen ovale120, as shown inFIG. 23.
• Preferably, thewire482 comprises a metal such as stainless steel, Nitinol, Elgiloy, or others which can be determined through routine experimentation by those of skill in the art. The wire may also be biodegradable. Wires having a circular or rectangular cross-section may be utilized depending upon the manufacturing technique. In one embodiment, a circular cross section wire is cut such as by known laser cutting techniques from tube stock. The closure device is preferably an integral structure, such as a single ribbon or wire, or element cut from a tube stock.
• The device may be similarly dimensioned as the embodiment ofFIG. 19A. For use in a patent foramen ovale, the overall width ofdevice470 may be any value or range of values from about 1 cm to about 5 cm, and, in one embodiment, may be about 2.5 cm. The overall length of theclosure device470 may be any value or range of values from about 4 cm to about 20 cm and is, in one embodiment, about 8 cm. Preferably the diameter of the wire may be any value or range of values from about 0.001-0.030 in, and in one preferred embodiment is about 0.015 in.
• In some embodiments, theanterior section472 may have a covering or be laminated.FIGS. 22B and 22C show the device ofFIG. 22B with alaminate structure483 covering theanterior section472. In some embodiments, the lamination may comprise any of a variety of materials which facilitate cellular in-growth, such as ePTFE. The suitability of alternate materials for the lamination material can be determined through routine experimentation by those of skill in the art. In one embodiment, two layers of lamination are provided. The two layers may be bonded to each other around thewire482 on theanterior section472 in any of a variety of ways, such as by heat bonding with or without an intermediate bonding layer such as polyethylene or FEP, adhesives, sutures, and other techniques which will be apparent to those of skill in the art in view of the disclosure herein. The lamination material in one embodiment preferably is securely attached to thedevice470 and retains a sufficient porosity to facilitate cellular ingrowth and/or attachment.
• Referring toFIGS. 24A-D, there is illustrated a preferred method of loading the device illustrated inFIG. 22B for delivery. A mountingshaft486 is inserted through thesecond loop481 of thedevice470 such that theanterior section472 is closer to theproximal end490 of the mountingshaft486 and theposterior section474 is closer to thedistal end488 of the mountingshaft486, as shown inFIG. 24A. As shown inFIG. 24B, theposterior section474 and theintermediate section476 are bent distally such that each wire of theintermediate section476 is placed along opposite sides of the mountingshaft486. The portion between theintermediate section476 and theposterior section474 rests on the mountingshaft486 with thethird loop484 extending somewhat radially from the mountingshaft486. Thethird loop484 is then bent over thedistal end488 of the mountingshaft486, as shown inFIG. 24C.
• Atether line492 is looped through thefirst loop480 on the proximal end of the device. A recapturewire494 is inserted through thetether line492 loop. The recapturewire494 preferably does not pass through thefirst loop480 of the device, as shown inFIG. 24D. When thetether line492 is drawn proximally, the tether line cinches thefirst loop480 of thedevice470. Thetether line492 is then drawn proximally such that theanterior section472 is an adjacent to the mountingshaft486. In another embodiment, the mountingshaft486 may first be inserted through thefirst loop480 and fixed with atether line492, followed by the mounting procedure as explained previously. Thedevice470,tether line492, recapturewire494, and mountingshaft486 are then inserted into a sheath (not shown).
• The placement of theclosure device470 is schematically shown inFIG. 23. For deployment, the sheath is advanced through thechannel122 of the patent foramen ovale, such that the distal end of the sheath extends into theleft atrium104 beyond thetip130 of theseptum primum116. The mountingshaft486 is held in place while the sheath is slowly retracted proximally until theposterior section474 is released from the sheath. Thewings479 of theposterior section474 may be extended out by slightly advancing the sheath distally while holding the mountingshaft486 in place. The mountingshaft486 and the sheath are then retracted proximally until thewings479 of theposterior section474 engage theseptum primum116. The mountingshaft486 is held in place while the sheath is retracted proximally allowing thewings479 to secure the septum primum. The sheath is then retracted further until theentire device470 is exposed.
• Thetether line492 and recapturewire494 are advanced distally, allowing theanterior section472 to advance and oppose the right atrium side of the septum secundum. With thetether line492 and recapturewire494 still secured to thefirst loop480, theentire device470 may be recaptured if required. Thetether line492 and recapturewire494 may also assist in repositioning theanterior section472 of the device. Optimal positioning of the device may be confirmed using fluoroscopy, echocardiography, or other imaging. Once optimal positioning is confirmed, the mounting shaft is retracted proximally, and the recapturewire494 is withdrawn proximally to release thetether line492 loop. The mountingshaft486,tether line492, recapturewire494, and sheath are then removed.
• Referring toFIGS. 25-32, there is illustrated another preferred embodiment of the present invention. The device is shown in an unexpanded state inFIGS. 25 and 26. Aclosure device500 is provided having a softdistal tip502, connected to adistal hub504, and a softproximal tip506, connected to aproximal hub508. The device also comprises at least two sealingarms510. The sealingarms510 are preferably heat-set. When the device is expanded, thearms510 have a generally round shape, as shown inFIG. 27. Thedevice500 also comprises at least twoanchors512,513 integrally formed with the distal andproximal hubs504,508 and the sealingarms510. The anchors deflect outwards upon expansion to retain the septum primum116 andseptum secundum118, as will be described. Thedevice500 is preferably made from a laser-cut hypotube. Thedistal hub504 andproximal hub508 are drawn together, thereby compressing thedevice500 and expanding the sealingarms510 for positioning in apatent foramen ovale120channel122.
• Preferably, theclosure device500 is provided with one or more retention structures for retaining the device in the patent foramen ovale or other similar septal defects. SeeFIG. 26. In the illustrated embodiment, a plurality of barbs or other anchoringelements522 are provided, for engaging adjacent tissue to retain theclosure device500 in its implanted position and to limit relative movement between the tissue and the closure device. The illustratedbarbs522 are provided on theanchors512,513. The barbs resist migration of the closure device away from the patent foramen ovale.
• Thearms510 are preferably positioned in thechannel122 between the septum primum116 and theseptum secundum118 to close thepatent foramen ovale120, as shown inFIG. 28. Afirst anchor513 is positioned in the left atrium, while asecond anchor512 is positioned in the right atrium. Theanchors512,513 deflect outwardly to secure the septum primum116 andseptum secundum118, to close thepatent foramen ovale120.
• Preferably, thedevice500 is formed of a metal such as stainless steel, Nitinol, Elgiloy, or others which can be determined through routine experimentation by those of skill in the art. The material may also be biodegradable. Material having a circular, rectangular, or other cross-section may be utilized depending upon the manufacturing technique. One of ordinary skill in the art will recognize various methods of manufacturing thedevice500. In one embodiment, for example, material with a circular cross section is cut such as by known laser cutting techniques from tube stock. The closure device is preferably an integral structure, such as a single ribbon or wire, or element cut from a tube stock.
• The device may also comprise a sleeve over at least a portion of the device. The sleeve may comprise any of a variety of materials which facilitate cellular in-growth, such as ePTFE. The suitability of alternate materials for sleeve can be determined through routine experimentation by those of skill in the art. In one embodiment, the sleeve comprises two layers. The two layers may be bonded to each other around the device in any of a variety of ways, such as by heat bonding with or without an intermediate bonding layer such as polyethylene or FEP, adhesives, sutures, and other techniques which will be apparent to those of skill in the art in view of the disclosure herein. The sleeve in one embodiment preferably is securely attached to thedevice500 and retains a sufficient porosity to facilitate cellular ingrowth and/or attachment.
• Thedevice500 is further provided with an expansion anddetachment element514 at its distal end. The expansion anddetachment element514 may be either a pull wire design (FIGS. 29-30), a turn screw design (FIGS. 31-32), a tether line, or other method known by one of ordinary skill in the art that may be used to collapse and lock the closure device in its expanded state. In one embodiment, the device is preferably attached viadetachment element514 to a delivery system as described above prior to deployment, and is then detached atdetachment element514 when properly positioned. The device can then be detached from the delivery system at the same place. In one embodiment, deployment and detachment of the device may be accomplished by torque rods, as discussed previously with reference toFIGS. 11A-B. In another embodiment, deployment and detachment may be accomplished by tether lines as previously discussed. Other methods that are known by one of ordinary skill in the art may also be used.
• Umbrella and Acorn Embodiments
• Referring toFIGS. 33-34, alternate structures of a closure device in accordance with the present invention are illustrated. Theclosure device600 comprises an occludingmember602 comprising aframe604 and abarrier606. In the illustrated embodiment theframe604 comprises a plurality of radially outwardly extendingspokes608 each having a length within the range of from about 1 cm to 6 cm. The device has aproximal end610 and adistal end612 corresponding to aproximal hub614 and adistal hub616. Acentral hub618 is also preferably provided between theproximal hub614 anddistal hub616. Theframe604 andbarrier606 form aproximal segment620 and adistal segment622. The designation proximal or distal is not intended to indicate any particular anatomical orientation or deployment orientation within the deployment catheter. Proximal anddistal segments620,622 are baskets which secure the septum primum116 andseptum secundum118 on both sides, thus sealing the patent foramen ovale.
• Thespokes608 are advanceable from a generally axially extending orientation such as from within a tubular introduction catheter to a radially inclined orientation. In a self-expandable embodiment, the spokes are biased radially outwardly such that the closure member expands to its enlarged, implantation cross-section under its own bias following deployment from the catheter. Alternatively, the closure member may be enlarged using any of a variety of enlargement structures such as an inflatable balloon, or a catheter for axially shortening the closure member, as is discussed further below. In yet a further embodiment, expansion of the device may be accomplished by torque rods, as discussed previously with reference toFIGS. 11A-B. Theproximal hub614 may threadingly engage the torque rod such that rotation of the torque rod will expand or contract thedevice600. Thedistal hub616 may operate to support the distal end of the torque rod, permitting the torque rod to rotate freely upon its axis with thedistal hub616. In another embodiment, thedistal hub616 may also be threadingly engaged to the torque rod.
• For deployment, thedevice600 is preferably advanced through thechannel122 of thepatent foramen ovale120 until the distal end of the catheter is beyond thetip130 of theseptum primum116. Thedevice600 is preferably advanced until thedistal end616 of thedevice600 extends into theleft atrium104. Thedistal segment622 is exposed from the catheter, such that it expands to its enlarged, implantation cross-section and engages the septum primum116 wall on theleft atrium104 side. Thedevice600 then is then drawn proximally to draw theseptum primum116 toward theseptum secundum118, closing thechannel122. Theproximal segment620 of thedevice600 is then exposed and permitted to expand to its enlarged, implantation cross-section, securing theseptum secundum118 to theseptum primum116.
• Depending upon the desired introduction crossing profile of thecollapsed closure device600, as well as structural strength requirements in the deployed device, anywhere within the range of from about 3 spokes to about 40 spokes may be utilized. In some embodiments, anywhere from about 12 to about 24 spokes are utilized, and 18 spokes are utilized in one embodiment.
• Preferably, the spokes comprise a metal such as stainless steel, Nitinol, Elgiloy, or others which can be determined through routine experimentation by those of skill in the art. Wires having a circular or rectangular cross-section may be utilized depending upon the manufacturing technique. In one embodiment, rectangular cross section spokes are cut such as by known laser cutting techniques from tube stock, a portion of which forms thehubs614,616,618.
• Thebarrier606 may comprise any of a variety of materials which facilitate cellular in-growth, such as ePTFE. The suitability of alternate materials forbarrier606 can be determined through routine experimentation by those of skill in the art. Thebarrier606 may be provided on either one or preferably both axially facing sides of the closure member. In one embodiment, thebarrier606 comprises two layers, with one layer on each side of theframe604. The two layers may be bonded to each other around thespokes608 in any of a variety of ways, such as by heat bonding with or without an intermediate bonding layer such as polyethylene or FEP, adhesives, sutures, and other techniques which will be apparent to those of skill in the art in view of the disclosure herein. Thebarrier606 preferably has a thickness of no more than about 0.003 in.
• For use in a patent foramen ovale, the occludingmember600 has an expanded diameter within the range of from about 10 mm to about 40 mm, and, in one embodiment, about 20 mm. The overall length of theclosure device600 from thedistal end612 to thedistal end610 is within the range of from about 40 mm to about 100 mm and, in one embodiment, about 70 mm.
• Modifications to the closure device are illustrated inFIGS. 35-36. Theclosure device650 comprises aclosure member652 comprising aframe654 and abarrier656. In the illustrated embodiment theframe654 comprises a plurality of radially outwardly extendingspokes658. The device has aproximal end660 and adistal end662, corresponding to aproximal hub664 and adistal hub666. Acentral hub668 is also preferably provided between theproximal hub664 anddistal hub666. Theframe654 andbarrier656 form aproximal segment670 and adistal segment672. The designation proximal or distal is not intended to indicate any particular anatomical orientation or deployment orientation within the deployment catheter. Proximal anddistal segments670,672 are concave faced baskets, which secure the septum primum and septum secundum on both sides, thus sealing the patent foramen ovale. Deployment of thedevice650 preferably corresponds to the deployment discussed above with reference toFIGS. 33-34.
• Referring to FIGS.37 and38A-B, a further variation of the closure device is shown. Theclosure device700 comprises aclosure member702 comprising aframe704 and abarrier706. In one embodiment, theframe704 comprises a plurality of radially outwardly extending supports (not shown). The device has aproximal end710 and adistal end712 corresponding to aproximal hub714 and adistal hub716. A softdistal tip718 is also preferably provided at thedistal end712, and is connected todistal hub716. Theframe704 andbarrier706 form aproximal segment720 and adistal segment722. The designation proximal or distal is not intended to indicate any particular anatomical orientation or deployment orientation within the deployment catheter. Proximal anddistal segments720,722 behave like baskets to secure the septum primum and septum secundum on both sides, thus sealing the patent foramen ovale.
• With reference toFIG. 38A, the device is shown in an unexpanded state. Proximal retraction on thedeployment line730 while resisting proximal movement ofproximal hub714 such as by using the distal end of thecatheter732 will cause thedistal hub716 to be drawn towards theproximal hub714, thereby radially enlarging the cross-sectional area of theclosure device700, as shown inFIG. 38B. Depending upon the material utilized for theclosure device700, the supports708 will retain the radially enlarged orientation by elastic deformation, or may be retained in the enlarged orientation such as by securing a slip knot immovably to thedeployment line730 at the fully radially enlarged orientation. This may be accomplished in any of a variety of ways, using additional knots, clips, adhesives, or other techniques known in the art. A variety of alternative structures may be utilized, to open or enlarge theclosure device700 under positive force, such as using a pullwire or a torque element, as will be discussed in further detail hereinafter. Deployment of thedevice700 preferably corresponds to the deployment discussed above with reference toFIGS. 33-34.
• With reference toFIGS. 39-41, theclosure device750 comprises an occludingmember752 comprising aframe754 and abarrier756. In the illustrated embodiment theframe754 comprises a plurality of radially outwardly extendingspokes758. The device has a proximal end760 adistal end762 corresponding to aproximal hub764 and adistal hub766. Acentral hub768 is also preferably provided between theproximal hub764 anddistal hub766. A softdistal tip769 is also preferably provided at thedistal end762, and is connected todistal hub766. Theframe754 andbarrier756 form aproximal segment770 and adistal segment772. The designation proximal or distal is not intended to indicate any particular anatomical orientation or deployment orientation within the deployment catheter. Proximal anddistal segments770,772 are umbrellas which secure the septum primum and septum secundum on both sides, sealing the patent foramen ovale. The proximal anddistal segments770,772 have a generally concave inwardly facingsurface774 and convex outwardly facingsurface776. The device is shown in a collapsed state inFIG. 41. Deployment of thedevice750 preferably corresponds to the deployment discussed above with reference toFIGS. 33-34.
• Referring toFIGS. 42-43 and45, a variation of the closure device is shown. Theclosure device800 comprises aframe804 and abarrier806. In the illustrated embodiment theframe804 comprises a plurality of radially outwardly extendingspokes808. The device has a proximal end810 adistal end812 corresponding to aproximal hub814 and adistal hub816. Theframe804 andbarrier806 form aproximal segment820 and adistal segment822. The designation proximal or distal is not intended to indicate any particular anatomical orientation or deployment orientation within the deployment catheter. Proximal anddistal segments820,822 are umbrellas which secure the septum primum and septum secundum on both sides, thus sealing the patent foramen ovale. The proximal anddistal segments820,822 have a generally flat inwardly facingsurface824 and an angled outwardly facingsurface826. Thedevice800 is shown in a collapsed position inFIG. 45. Deployment of thedevice800 preferably corresponds to the deployment discussed above with reference toFIGS. 33-34.
• Referring toFIGS. 44A-C, aclosure device1400 is preferably positioned within a septal defect to be occluded, such as a patent foramen ovale or an atrial septal defect. In a patent foramen ovale application, thedistal end1402 of thedelivery catheter1404 is positioned at or near thepatent foramen ovale120. The position may be confirmed using fluoroscopy, echocardiography, or other imaging. Thedevice1400 is initially in a collapsed state incatheter1404. The actuator1408 (shown inFIG. 44C) is thereafter proximally retracted or rotated, as with a torque rod, to place and expand theclosure device1400 at thepatent foramen ovale120.
• As will be apparent fromFIG. 44B, proximal retraction or rotation on theactuator1408 while resisting proximal movement ofproximal hub1410 such as by using the distal end of thecatheter1404 will cause thedistal hub1412 to be drawn towards theproximal hub1410. Theclosure device1400 engages the septa walls thereby closing the patent foramen ovale.
• The actuator may then be locked with respect to the proximal hub and severed or otherwise detached to enable removal of the deployment catheter and proximal extension of the actuator. Locking of theactuator1408 with respect to theclosure device1400 may be accomplished in a variety of ways, such as by using interference fit or friction fit structures, adhesives, a knot or other techniques depending upon the desired catheter design, as discussed herein. After thedevice1400 is locked in placed, thecatheter1402 is detached from thedevice1400 and removed from the patient. SeeFIG. 44. Thedevice1400 can also be captured and retrieved at any time during the procedure as long as it is not detached from the delivery catheter.
• With reference toFIG. 46, an alternative embodiment of the closure device is shown. Theclosure device850 comprises a proximalinflatable balloon852 and a distalinflatable balloon854 joined together at acentral hub856. Thedevice850 may also comprise a frame, comprising a plurality of supports. Thedevice850 is preferably expanded by inflating theballoons852,854 via an inflation catheter by inserting inflation fluid throughinflation lumen858. Thecentral hub856 is positioned within the patent foramen ovale, while theproximal balloon852 is preferably positioned in the right atrium and thedistal balloon854 is positioned in the left atrium, to occlude the patent foramen ovale.
• Any modifications to the device to accommodate these various aspects of the closure device as discussed herein may be readily accomplished by those of skill in the art in view of the disclosure herein.
• Tack Embodiments
• With reference toFIGS. 47 and 48, alternative embodiments are shown. In these embodiments, the patent foramen ovale is simply held together by positioning adevice900,950 to hold the septum primum116 andseptum secundum118 together. In a first embodiment, thedevice900 comprises aproximal end906 and adistal end908, having aproximal anchor910 and adistal anchor912. Alternatively, adevice950 comprises aproximal end956 and adistal end958. The device has a screw-like configuration and comprises a coiled wire or threadedscrew960. Theproximal end906,956 is preferably positioned in the right atrium, while thedistal end908,958 is positioned in the left atrium. Thedevice900,950 includes adetachment zone914,964. The device may also be provided with a sleeve, as has been discussed with previous embodiments.
• Preferably, thedevice900,950 is formed of a metal such as stainless steel, Nitinol, Elgiloy, or others which can be determined through routine experimentation by those of skill in the art. The wire may also be biodegradable. Wires having a circular or rectangular cross-section may be utilized depending upon the manufacturing technique. In one embodiment, a circular cross section wire is cut such as by known laser cutting techniques from tube stock. The closure device is preferably an integral structure, such as a single ribbon or wire, or element cut from a tube stock.
• In another preferred embodiment, with reference toFIGS. 49-51, aclosure device1000 comprising a closure member is shown. The device comprises aproximal end1002 and adistal end1004, and acircular proximal section1006 and circulardistal section1008, which are connected via acenter strut1010, forming an integral structure. Thecenter strut1010 preferably contains a closure orthrombotic material1011. Aloop1012 is provided for holding and retrieving thedevice1000. The proximal anddistal sections1006,1008 act like springs, and maintain stability and help to squeeze the patent foramen ovale.
• Thecenter strut1010 rests within thepatent foramen ovale120 for occluding thechannel122, engaging the septum primum116 and theseptum secundum118. Theproximal section1006 is preferably positioned in the right atrium, while thedistal section1008 is positioned in the left atrium.
• Preferably, thedevice1000 is formed of a metal such as stainless steel, Nitinol, Elgiloy, or others which can be determined through routine experimentation by those of skill in the art. The wire may also be biodegradable. Wires having a circular or rectangular cross-section may be utilized depending upon the manufacturing technique. In one embodiment, a circular cross section wire is cut such as by known laser cutting techniques from tube stock. The closure device is preferably an integral structure, such as a single ribbon or wire, or element cut from a tube stock.
• Thethrombotic material1011 may include DACRON™, or others which can be determined through routine experimentation by those of skill in the art.
• Channel-Filling Embodiments
• With reference toFIG. 52, there is illustrated another preferred embodiment of the present invention. Aclosure device1050 comprising a porous sponge or sponge-like material is shown. Alternatively, theclosure device1050 may comprise a fluid-filled bag with a porous or semi-porous other covering. In some embodiments, theclosure device1050 has a generally cylindrical shape. In some embodiments, the sponge is at least as large as the defect to be filled. In some embodiments,tether1055 extends throughclosure device1050 and is used to attachclosure device1050 todelivery catheter1504.FIG. 53 illustrates the sponge-like closure device1050 positioned at a patent foramen ovale. The sponge expands upon placement to close the defect and is secured in place by the septum primum116 andseptum secundum118.
• In some embodiments, the sponge or sponge-like material may comprise collagen, PE, PTFE, Poly Vinyl Acetate (Ivalon), or Ethyl Vinyl Acetate. In some embodiments, the material may be bioresorbable. In some embodiments, the sponge promotes tissue ingrowth for more complete sealing of a septal defect, such as a patent foramen ovale.
• With reference toFIG. 54, ananchor device1060 is illustrated. Theanchor device1060 comprises aframe1062 having a plurality ofretention elements1064 provided thereon. In some embodiments, the frame may be perforated, while in other embodiments, the frame is solid.
• In some embodiments, theanchor device1060 may be comprised of a plurality of laser cut strips1065, as shown inFIG. 55. The laser cut strips comprise a laser-cut body1066 which can be twisted to revealanchors1068. A detailed view of thebody1066 and anchors1068 is shown inFIG. 56. By linking together a plurality of the laser cut strips1065, a lattice of anchoring surfaces can be formed. The lattice of anchoring surfaces can also be placed within or through a patent foramen ovale.
• As shown inFIG. 57, theanchor device1060 may be used with the sponge-like closure device1050 to form an anchoredsponge closure device1070. The anchors may be used to further secure the sponge-like closure device in place.FIG. 58 illustratesclosure device1070, whereinanchor devices1060 secure the sponge-like closure device1050 at a defect.
• Referring toFIG. 59A-C, a preferably method is shown of deploying theclosure device1500 within a septal defect, such as a patent foramen ovale. In a patent foramen ovale application, thedistal end1502 of thedelivery catheter1504 is positioned at or near thepatent foramen ovale120, as shown inFIG. 59A. The position may be confirmed using fluoroscopy, echocardiography, or other imaging. Thedevice1500 is initially in a collapsed state withincatheter1504. Thedevice1500 may be releasably attached to anactuator1508. Thedistal end1502 of thedelivery catheter1504 is advanced between the septum primum116 andseptum secundum118 as shown, and theposterior portion1510 is advanced out of thedistal end1502 of thedelivery catheter1504, as shown inFIG. 59B. The intermediate section and posterior sections are then delivered, as shown inFIG. 59C. After optimal positioning and sealing is achieved, thedevice1500 can then be detached from thedelivery catheter1504.
• Any of the closure devices disclosed herein may also be coated with a therapeutic substance, such as an anti-thrombogenic drug. The therapeutic substances are typically either impregnated into the device or carried in a polymer that coats the device. The therapeutic substances are released from the device or polymer once it has been implanted in the vessel. The device may be impregnated with at least one drug or coated with at least one drug by any known process in the art. The drug may be carried in a volatile or non-volatile solution. As used in this application, the term “drug” denotes any compound which has a desired pharmacological effect, or which is used for diagnostic purposes.
• Furthermore, the closure devices as disclosed herein are preferably asymmetrical. As has been discussed, the axis of a patent foramen ovale tends to be at an angle, and almost parallel to the septal wall. Accordingly, asymmetrical closure devices will be effective in closing septal defects having non-longitudinal axes, such as a patent foramen ovale.
• As a post implantation step for any of the closure devices disclosed herein, a radiopaque dye or other visualizable media may be introduced on one side or the other of the closure device, to permit visualization of any escaped blood or other fluid past the closure device. For example, in the context of a patent foramen ovale application, the closure device may be provided with a central lumen or other capillary tube or aperture which permits introduction of a visualizable dye from the deployment catheter through the closure device and into the space on the distal side of the closure device.
• While particular forms of the invention have been described, it will be apparent that various modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is not intended that the invention be limited, except as by the appended claims.

Claims (19)

1-7. (canceled)

8. A system for closing a patent foramen ovale with an overlapping septum primum and a septum secundum, comprising:

a delivery catheter having a lumen extending therethrough;

a closure device configured for being configured for placement in the opening in the heart and for collapsible containment within the lumen, the closure device comprising:

a wire;

an anterior section;

a posterior section;

at least one loop;

at least one wing configured to anchor the device into heart tissue; and

a tether extending through the at least one loop, the tether configured to releasably retain the closure device with the delivery catheter.

9. The system for closing a patent foramen ovale ofclaim 8, wherein the tether extends through the lumen and is detachable from the at least one loop.

10. The system for closing a patent foramen ovale ofclaim 8, wherein the closure device is self-expandable.

11. The system for closing a patent foramen ovale ofclaim 8, wherein the wire, anterior section, posterior section and at least one loop are integral.

12. The system for closing a patent foramen ovale ofclaim 8, wherein the wire comprises Nitinol.

13. The system for closing a patent foramen ovale ofclaim 8, wherein the wire comprises stainless steel.

14. The system for closing a patent foramen ovale ofclaim 8, the wings extending beyond the overlapping septum primum and a septum secundum of the patent foramen ovale to provide additional support to closure device.

15. The system for closing a patent foramen ovale ofclaim 8, further comprising a material attached to the closure device configured to facilitate cellular in-growth.

16. A system for closing a defect in a human heart, comprising:

a wire frame having expandable anterior and posterior sections, wherein the wire frame is biased to be expanded such that the anterior and posterior sections engage tissue on opposite sides of the defect, and the wire frame is configured to be retrieved by collapsing the wire frame;

at least one loop in the anterior section of the wire frame;

at least one wing configured to anchor the device into heart tissue; and

a tether passing through the at least one loop; and

a delivery catheter having a lumen for delivering the wire frame in a collapsed configuration to the defect.

17. The system ofclaim 16, wherein the posterior section includes a plurality of loops extending radially outwardly.

18. The system ofclaim 16, further comprising a material on at least a portion of the wire frame configured to promote tissue growth.

19. The system ofclaim 18, wherein the material is formed of a relatively porous material for permitting ingrowth of collagen or fibrous tissue into the material.

20. The system ofclaim 16, comprising a plurality of loops in the anterior section of the wire frame and a plurality of tethers passing through the loops.

21. A tissue opening occluder for placement in an area formed by overlapping atrial septa of a patent foramen ovale (PFO), the overlapping atrial septa forming a PFO tunnel, the PFO tunnel having a generally planar geometry along a length of the tunnel from the left atrium to the right atrium, the tissue opening occluder comprising:

a planar support structure sized and configured to be deployed into position within the PFO tunnel between the overlapping atrial septa with a planar portion of the planar support structure configured to be generally parallel with a tissue wall extending along a length of the PFO tunnel from the left atrium to the right atrium, the planar portion comprising a first substantially planar tissue engaging side and a second substantially planar tissue engaging side, the planar portion having a flat configuration defined between the first and second substantially planar tissue engaging sides;

at least one wing configured to anchor the device into heart tissue; and

a material supported by the planar support structure and sized and configured to be positioned within the PFO tunnel between the overlapping atrial septa, the material promoting tissue growth to anchor the occluder in intimate contact with a tissue wall.

22. The tissue opening occluder ofclaim 21, wherein the material is porous.

23. The tissue opening occluder ofclaim 21, wherein the support structure is made of metal wire.

24. The tissue opening occluder ofclaim 21, wherein the planar support structure further comprises at least one loop selectively attachable to a tether.

25. The tissue opening occluder ofclaim 21, wherein the planar support structure further comprises wings configured to anchor the support structure into heart tissue.

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