US20050107810A1 - Devices and methods for heart valve repair - Google Patents

Abstract

Methods and devices provide constriction of a heart valve annulus to treat cardiac valve regurgitation and other conditions. Embodiments typically include a device for attaching a cinching or tightening apparatus to a heart valve annulus to reduce the circumference of the annulus, thus reducing valve regurgitation. Tightening devices may include multiple tethered clips, multiple untethered crimping clips, stabilizing devices, visualization devices, and the like. In one embodiment, a plurality of tethered clips is secured circumferentially to a valve annulus, and the tether coupling the clips is cinched to reduce the circumference of at least a portion of the annulus. Methods and devices may be used in open heart surgical procedures, minimally invasive procedures, catheter-based procedures, and/or procedures on beating hearts or stopped hearts.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS
• This application is a division of and claims the benefit of priority from U.S. patent application Ser. No. 10/461,043 (Attorney Docket No. 016886-000310US), filed Jun. 13, 2003, which claimed the benefit under 35 USC 119(e) of U.S. Provisional Application Nos. 60/388,935 (Attorney Docket No. 016886-000300US), filed on Jun. 13, 2002; 60/429,288 (Attorney Docket No. 016886-000700US), filed on Nov. 25, 2002; 60/445,890 (Attorney Docket No. 016886-000800US), filed on Feb. 6, 2003, and 60/462,502 (Attorney Docket No. 016886-001100US), filed on Apr. 10, 2003, the full disclosures of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
• 1. Field of the Invention
• The present invention relates generally to medical methods and devices. More particularly, the invention relates to methods and devices for circulatory valve repair, especially for the repair of heart valves, such as repair of the mitral or tricuspid valve for treating mitral or tricuspid regurgitation.
• Four valves in the heart direct blood flow through the heart in a forward direction. On the left side of the heart, the mitral and aortic valves direct oxygenated blood from the lungs to the aorta for distribution to the body. On the right side of the heart, the tricuspid and pulmonary valves direct de-oxygenated blood from the body to the pulmonary arteries for distribution to the lungs.
• The four heart valves consist of moveable leaflets that open and close in response to differential pressures on either side of the valve. The mitral valve, for example, has two leaflets while the tricuspid valve has three. The components of the mitral valve assembly include a mitral valve annulus, an anterior leaflet, a posterior leaflet, two papillary muscles which are attached at their bases to the interior surface of the left ventricular wall, and multiple chordae tendineae, which are cord-like structures that couple the mitral valve leaflets to the papillary muscles. The other heart valves have similar supporting structures, though each is somewhat unique.
• If a functional problem occurs in one or more heart valves, cardiac function is often adversely affected. Such valve problems may be classified as either stenosis, in which a valve does not open properly, or insufficiency (also known as regurgitation), in which a valve does not close properly. Mitral regurgitation, for example, is typically caused by dysfunction of the mitral annulus, subvalvular apparatus, or direct injury to the valve leaflets. Severe mitral regurgitation is a serious problem which, if left untreated, can adversely affect cardiac function and compromise a patient's quality of life and longevity. In cases where an atrioventricular valve becomes regurgitant due to damage to the valve supporting structures, papillary muscles, leaflets or annular geometry, the fraction of blood in the ventricle that is actually moved forward with each beat is reduced. To compensate, the ventricular cavity enlarges in an attempt to maintain forward output. By enlarging, the heart attempts to maintain the same absolute volume of forward flow by ejecting a reduced percentage of a larger volume. This enlargement of the ventricle is accompanied by an enlargement of the supporting structures and annulus of the valve, resulting in separation of the valve leaflets at their point of co-aptation during ventricular systole and further leaking of blood retrograde across the valve. This continues the cycle of ventricular enlargement, annular dilatation and regurgitation and subsequent loss of forward output and progressive heart failure. Other heart valve problems often cause similarly grave sequelae.
• Treatment of heart valve stenosis or regurgitation, such as mitral or tricuspid regurgitation, often involves an open-heart surgical procedure to replace or repair the valve. Repair of a regurgitant valve such as the mitral valve is often performed in preference to replacement. Such procedures generally require a large incision into the thorax of the patient (a thoracotomy), sometimes requiring a median sternotomy (cutting through the middle of the sternum). Such procedures routinely include a corrective procedure called an annuloplasty, designed to restore the valve annulus shape, strengthen the annulus, and allow better leaflet co-aptation as a part of the repair. Such open heart procedures also usually involve placing the patient on a cardiopulmonary bypass machine for sustained periods so that the patient's heart and lungs can be artificially stopped during the procedure. Finally, valve repair and replacement procedures are typically technically challenging and require that a relatively large incision be made through the wall of the heart to access the valve. Due to the highly invasive nature of open heart valve repair or replacement, many patients, such as elderly patients, patients having recently undergone other surgical procedures, patients with comorbid medical conditions, children, late-stage heart failure patients and the like, are often considered too high-risk to undergo heart valve surgery and are committed to progressive deterioration and cardiac enlargement. Often, such patients have no feasible alternative treatments for their heart valve conditions.
• Therefore, it would be advantageous to have methods and devices for repairing a mitral valve to treat mitral regurgitation in a less invasive manner than is available through current techniques. In some instances, it may be advantageous to provide for repair of a mitral valve, as well as other heart valves, through minimally invasive incisions or intravascularly. In other cases, it may be beneficial to use improved devices and methods in an open heart surgical procedure, on either a beating heart or a stopped heart. In beating heart procedures, including both minimally invasive and intravascular access procedures, it would be useful to provide for stabilization of the valve annulus while any procedure is being performed. In such beating heart procedures, it would be further useful to provide systems for the direct observation of the valve annulus from within a heart chamber to facilitate performing desired interventions. Moreover, it would be still further desirable if the apparatus and systems of the present invention were useful for treating not only the annulus of heart valves, but also other natural and created holes in tissue which require strengthening or closing. Improved devices and methods would ideally be relatively simple and easy to use and would enable durable, long-lasting mitral valve repair, either in a minimally invasive or open heart procedure, for many patients who are not candidates for more conventional procedures. At least some of these objectives will be met by the present invention.
• 2. Description of the Background Art
• Published U.S. Application 2002/0163784A12 describes a port for providing access to a beating heart to perform diagnostic and therapeutic procedures, including a stapled annuloplasty procedure. Published U.S. Application 2002/0042621 describes a heart valve annuloplasty system with constrictable plication bands which are optionally attached to a linkage strip. Published U.S. Application 2002/0087169 describes a remote controlled catheter system which can be used to deliver anchors and a tether for performing an annuloplasty procedure. Other patent publications of interest include WO01/26586; US2001/0005787; US2001/0014800; US2002/0013621; US2002/0029080; US2002/0035361; US2002/0042621; US2002/0095167; and US2003/0074012. U.S. patents of interest include U.S. Pat. Nos. 4,014,492; 4,042,979; 4,043,504; 4,055,861; 4,700,250; 5,366,479; 5,450,860; 5,571,215; 5,674,279; 5,709,695; 5,752,518; 5,848,969;5,860,992; 5,904,651; 5,961,539; 5,972,004; 6,165,183; 6,197,017; 6,250,308; 6,260,552; 6,283,993; 6,269,819; 6,312,447; 6,332,893; and 6,524,338. Publications of interest include De Simone et al. (1993)Am. J. Cardiol.73:721-722 and Downing et al. (2001)Heart Surgery Forum, Abstract7025.
BRIEF SUMMARY OF THE INVENTION
• Methods and devices provide heart valve repair for mitral valve regurgitation and other heart valve conditions. Embodiments typically include a device for attaching a cinching or tightening apparatus to a heart valve annulus to reduce the circumference of the annulus, thus reducing valve regurgitation. Tightening devices include multiple tethered clips, multiple tethered or untethered crimping (deformable) clips, apparatus for delivering such clips, apparatus for selectively deforming clips onto the tether, systems for stabilizing the valve annulus during interventions, systems for viewing the valve annulus during an intervention, and the like.
• As used hereinafter, the term “clips” is intended to refer to a wide variety of tissue anchors or fasteners which are able to (1) penetrate and fix to tissue, particularly into the fibrous tissue of a heart valve annulus and (2) provide for a secure attachment to a tether. Usually, the clips will initially be slidably received over the tether, e.g., through eyelets as described in greater detail hereinafter. Particular ones of the clips, however, may be fixedly secured to the tether even at the outset of the procedure. For example, often at least a first clip will be fixed to a lead end of the tether, where the first clip will be initially deployed into the annulus and will serve as an anchor at one end of the tether which is deployed about the annulus. Usually the remaining clips, including a series of intermediate clips and at least one terminal clip, will remain slidably secured over the tether until one of more of those clips is crimped or otherwise fixed to the tether during the interventions, as described in more detail below.
• While the methods of the present invention are directed particularly at constricting a valve annulus, particularly for the treatment of valve regurgitation, the apparatus of the present invention may find broader applications. In particular, the clip deploying apparatus of the present invention may be used whenever it is desired to deliver a plurality of sequential clips, either in a straight line or in a curved line, in order to tighten tissue or optional to tether portions of tissue which are separate or which have been traumatically severed. Thus, the apparatus claimed herein are not meant to be limited in any way by the exemplary methods in which they are being used.
• Generally, in accordance with the principles of the present invention, a plurality of tethered clips is secured circumferentially to a valve annulus, and the tether coupling the clips is cinched to reduce the circumference of at least a portion of the annulus. Optionally, at least a terminal clip may be deformed, such as by crimping, to secure the clip(s) to the tether, and the tether may pass through one, two or more eyelets on each clip. Methods and devices may be used in open heart surgical procedures, minimally invasive procedures and/or procedures on beating hearts or stopped hearts. Furthermore, a heart valve may be accessed by any suitable route, such as any veinous access route, through any incision(s) in the heart wall and/or atrial septum, through any heart chamber and/or through the aorta.
• In one aspect of the invention, a method for constricting a valve annulus comprises introducing a plurality of clips to a heart valve annulus, the clips being coupled with a tether, securing individual clips at circumferentially spaced-apart locations about at least a portion of the annulus, and cinching the tether to circumferentially tighten the annulus. At least a first clip at a lead end of the tether is usually fixed to the tether, and the remaining clips are usually slidably coupled to the tether to facilitate cinching. Often, all of a series of intermediate clips and at least a single terminal clip will be introduced to the annulus prior to cinching by applying tension to the free end of the tether. After the proper amount of tension is applied, the terminal clip(s) will then be crimped onto or otherwise fixed to the tether to maintain the desired degree of annular constriction. Of course, it may be desirable to crimp or otherwise fix two or more clips at the lead end of the tether and/or two or more clips at the terminal end of the tether to help assure that the tether will not loosen. In some instances, it may even be desirable to deform or otherwise fix each and every clip to the tether after the desired level of cinching has been achieved. In general, however, the methods of the present invention will not rely on cinching a clip immediately after that clip is placed in order to placate tissue between adjacent clips. Deforming the portion of the at least one clip may involve applying force to at least one eyelet on the clip to reduce the inner diameter of the eyelet and secure the tether within the eyelet. Some embodiments may involve deforming two eyelets on a clip to secure the tether within each of the two eyelets.
• In some embodiments, introducing the plurality of clips comprises advancing a tethered clip applicator through an incision in a wall of the heart to a desired location for treating the heart valve annulus. For example, the applicator will be introduced through an incision in the left atrial wall of the heart in some embodiments, to a location at or near the posterior or anterior commisure of the mitral valve annulus. Some embodiments further include placing an instrument introduction device through the incision in the wall of the heart, and the clip applicator is advanced through the instrument introduction device. Optionally, such embodiments may also include securing the introduction device to the heart wall before the advancing step. In some embodiments, the instrument introduction device comprises a valve, a diaphragm and/or a hemostatic barrier for allowing passage of the clip applicator and any other devices while preventing outflow of blood from the heart. In one embodiment, for example the clip applicator is generally an elongate hand-held applicator, insertable through the introduction device.
• In some embodiments, securing the individual clips comprises securing a first tethered clip to the heart valve annulus and securing a plurality of subsequent tethered clips at circumferentially spaced-apart locations about at least a portion of the annulus. In some cases, the first clip is pre-secured the tether. In other cases, securing the first tethered clip to the valve annulus includes deforming a portion of the first tethered clip to secure it to the tether. Alternatively, a portion of the first tethered clip may be deformed after securing the clip to the annulus to secure the first clip to the tether. In still other embodiments, a portion of the first tethered clip may be deformed before securing the clip to the annulus to secure the first clip to the tether. In some embodiments, the plurality of subsequent tethered clips are slidably coupled with the tether. Optionally, such embodiments may further include deforming a portion of at least a second clip to secure the second clip to the tether.
• In some embodiments, cinching generally involves applying tensile force to the tether. A method may further include deforming a portion of at least one of the plurality of subsequent tethered clips after the cinching step to secure the at least one partially-deformed clip to the tether. For example, deforming a portion of the at least one clip may involve deforming a last clip of the subsequent tethered clips. Optionally, such embodiments may further include deforming at least a penultimate clip of the subsequent tethered clips.
• Some embodiments also include securing a tether anchor, coupled to the tether, to the valve annulus adjacent a last clip of the individual clips. For example, securing the tether anchor may involve securing a rivet to the valve annulus. Such embodiments may also include deforming a portion of the last clip around the rivet to secure the tether to the rivet and secure the last clip to the annulus. Optionally, a portion of a penultimate clip may also be deformed around the rivet to secure the tether to the rivet and secure the penultimate clip to the annulus.
• Some embodiments of the method further involve visualizing the heart valve using at least one visualization device. For example any one of (or combination of) an ultrasound device, an angioscopic device, a transesophageal echocardiogram device and a fluoroscopic device may be used for visualization. In some embodiments, an ultrasound device comprising a gel-containing cone for enhancing ultrasound visualization may be used. Some embodiments may involve using a real-time Doppler ultrasound device to visualize a regurgitant flow across the heart valve during at least the cinching step. Optionally, such methods may also include visualizing a reduction in the regurgitant flow during the cinching step and selecting an amount of cinching based on the reduction in the regurgitant flow in real time. Particularly useful visualization may be accomplished using optical viewing elements disposed directly in the heart chamber, typically adjacent to the valve annulus or other target tissue being treated. Particularly in beating heart procedures, such optical visualization will be accomplished using a transparent element to exclude blood, such as a lens, a solid optically transparent block, or most preferably a transparent inflatable balloon which may be inflated with a transparent inflation medium. By engaging such balloon against the surface to be visualized, direct and highly accurate visualization of the annulus may be accomplished. In some embodiments, the optical or other visualization device is coupled with a device for introducing and securing the clips, such as the clip applicator.
• As mentioned above, the introducing, securing and cinching steps may be performed as part of any suitable procedure, from any suitable access route, and the like. For example, the may be performed as part of an open heart surgical procedure, with or without stopping the heart, through one or more minimally invasive incisions and/or intravascularly. Furthermore, any suitable cardiovascular valve may be treated, such as the mitral valve, tricuspid valve or the like.
• In another aspect, a method for inhibiting heart valve regurgitation comprises: introducing a plurality of crimping clips to a heart valve annulus; securing individual crimping clips at circumferentially spaced-apart locations about at least a portion of the annulus; and crimping at least one of the clips to circumferentially tighten the annulus. Crimping clips may generally be tethered or untethered, but in one embodiment the crimping clips are slidably coupled with a tether, and the method further includes cinching the tether to circumferentially tighten the annulus. Cinching typically involves applying tensile force to the tether. In some embodiments, crimping a tethered clip secures the crimped clip to the annulus and to the tether. In some embodiments, for example, crimping a clip comprises compressing at least one eyelet in the clip, the tether running through the eyelet. In some embodiments, the clips each have two eyelets and the tether runs through the two eyelets on each clip.
• In some embodiments, crimping comprises crimping a first clip before the cinching step to secure the first clip to the annulus and the tether and crimping at least a last clip after the cinching step to secure the last clip to the annulus and the tether. Various embodiments may further include crimping at least a penultimate clip to secure the penultimate clip to the annulus and the tether. Crimping may further involve crimping at least the last clip around a tether anchor to secure the last clip to the tether anchor and secure the tether anchor to the annulus.
• In many embodiments, at least the introducing and securing steps are performed using an elongate, hand-held, surgical device. The surgical device may include an actuator at or near its proximal end for performing at least the securing step. In some embodiments, for example, the actuator may include, but is not limited to a trigger, a handle, a plunger, a squeeze-activated device and a syringe-grip device.
• In yet another aspect, a method for inhibiting heart valve regurgitation comprises securing a flexible cord about at least a portion of the annulus of the valve and cinching the flexible cord to reduce the annular circumference. As with the above procedures, such a method may be performed as part of an open heart surgical procedure, with or without stopping the heart, through one or more minimally invasive incisions, intravascularly, or via any other suitable approach.
• In some embodiments, securing and cinching are performed through a small incision in a wall of the heart. Such embodiments may further include placing an instrument introduction device in the heart wall through the incision before performing the securing and cinching steps. This method may further include securing the instrument introduction device to the wall. The instrument introduction device may include, for example, a valve for allowing passage of one or more surgical instruments while preventing outflow of blood from the heart through the valve. The method may optionally further include introducing at least one surgical instrument into a chamber of the heart through the instrument introduction device. For example, at least one elongate, hand-held instrument may be introduced for performing the securing and cinching steps.
• As described above, in any of the above methods, one or more visualization devices may be used, such as ultrasound and/or transesophageal echocardiogram devices. Also as mentioned above, the methods may be used to operate on any suitable cardiovascular valves, such as a mitral, tricuspid, aortic or pulmonary valve.
• In still further embodiments of the methods of the present invention, a heart valve annulus of a beating heart is constricted by first stabilizing the heart valve annulus. After the annulus is stabilized, individual clips are secured at circumferentially spaced-apart locations about at least a portion of the annulus. A tether passed through the clips may be cinched in order to circumferentially tighten the annulus. Stabilization of the beating heart is very beneficial in both minimally invasive and intravascular (closed-chest) procedures.
• The valve annulus may be stabilized in a variety of ways. Usually, stabilization will involve engaging the annulus with at least a first stabilizing ring which is typically in the case of a mitral valve disposed beneath the valve leaflets to engage an intersection between the leaflets and the interior ventricular wall. Usually, the stabilization ring will be introduced from the left atrium, together with the other interventional tool(s), to a location at the valve commisure. A curved or C-shaped component of the stabilizer will then be deployed beneath the valve annulus. Preferably, a second stabilization ring will be introduced to a location above the valve annulus, where the first and second stabilizing rings will typically have similar or congruent geometries permitting clamping of the valve annulus therebetween. Optionally, either or both of the stabilizing rings may be further provided with a vacuum source, microhooks, adhesives, or the like to assist in engaging and capturing the tissue of and surrounding the valve annulus. Still further optionally, the stabilization ring disposed above the valve annulus may be adapted to deliver clips directly to the tissue, thus in some cases eliminating the need for a separate clip applier as described elsewhere in this application. Alternatively, of course, the clips may be successively applied from an applicator, as described elsewhere herein, which is advanced around at least a portion of the valve annulus while the valve annulus remains stabilized. When using a separate clip applicator, the stabilizing ring or other stabilization apparatus may provide a template to guide the applicator around the annulus as clips are applied. In most cases, the stabilization device will also shape the annulus to a geometry compatible with the applicator. After the clips are delivered, the rings or other stabilizing device will be removed, and the tether cinched to constrict the annulus as described elsewhere herein.
• In yet another aspect of the method of the present invention, valve annulus may be constricted in a beating heart while directly viewing at least a portion of the valve annulus from within the atrium (left atrium in the case of the mitral valve). Individual clips are secured at circumferentially spaced-apart locations about at least a portion of the valve annulus while annulus remains under direct viewing. After the clips are properly placed, as confirmed by direct viewing, the tether may be cinched through the clips to circumferentially tighten the annulus, as generally described elsewhere in the application. Such direct viewing may be accomplished using an ultrasonic imaging element, for example one placed on a clip applier. More preferably, however, direct viewing may be accomplished by engaging a transparent element against the valve annulus and optically viewing the annulus through said element. Usually, the transparent element comprises an inflatable balloon which is inflated with a transparent inflation medium. Optical viewing may then be performed from within the inflated balloon using a fiberoptic scope, a CCD (charged coupled device), other type of camera, or the like.
• In yet another aspect, a device for applying tethered clips to a heart valve annulus comprises a shaft having a proximal end and a distal end and a plurality of clips slidably coupled to a tether. The tethered clips are carried by the shaft; and the device further includes a clip applier at or near the distal end of the shaft for securing the clips to the annulus and at least one actuator at or near the proximal end of the shaft for causing the device to advance the clips and for activating the clip applier to secure the clips to the annulus. Optionally, the means for selectively advancing and securing the clips may further comprise a pusher coupled with the actuator for advancing the clips and at least one slot in an inner surface of the shaft for guiding the clips.
• In some embodiments, the clip applier comprises a clip crimping member. Also in some embodiments, the at least one actuator includes means for tensioning and cinching the tethered clips to reduce the circumference of the valve annulus. The actuator itself may comprise any suitable device(s), such as but not limited to a trigger, a handle, a plunger, a squeeze-activated device, a syringe-grip device and/or any suitable foot-operated device.
• In some embodiments, each of the plurality of clips includes at least one eyelet, and the tether passes through the eyelet of each clip. Optionally, in some embodiments, each clip includes two eyelets, and the tether passes through both eyelets of each clip. In such embodiments, the device may further include means for crimping the at least one eyelet of any of the plurality of clips such that a clip with a crimped eyelet is secured to the tether.
• In some embodiments, the shaft comprises an elongate, hand-held shaft. Optionally, the shaft may be introducible into a patient through a minimally invasive incision. In these or other embodiments, a tether anchor may be coupled to the tether and carried by the shaft. For example, the tether anchor may comprise a rivet. The tether anchor may be coupled with at least a last clip of the tethered clips such that crimping the last clip secures the last clip to the tether anchor and the tether anchor to the tether. In some embodiments, the tether anchor is further coupled with a penultimate clip, such that crimping the penultimate clip secures the penultimate clip to the tether anchor and the tether anchor to the tether.
• The tether itself may comprise any material or configuration. In some embodiments, for example, the tether comprises at least one of a suture material, a Teflon strip, a band, a filament, a wire and a strap. Embodiments including tethers may optionally also include means for cinching the tethered clips to reduce the circumference of the valve annulus.
• In another aspect, a device for applying tethered clips to a heart valve annulus comprises: a shaft having a proximal end and a distal end, a plurality of clips slidably coupled to a tether, the tethered clips carried by the shaft; a clip applier at the distal end of the shaft for securing the clips to the valve annulus; and tensioning means for providing tension to the tether to cinch the tether, thus reducing a diameter of the valve annulus. In some embodiments, the clip applier comprises means for partially deforming at least one of the clips to secure the deformed clip(s) to the tether. In some embodiments, the tensioning means allows for tensioning of the tether while the clips are being secured to the valve annulus. Optionally, the device may further include cutting means at the distal end of the shaft for cutting an end of the tether after the clips have been secured and cinched.
• In still another aspect or the invention, a device for treating heart valve regurgitation includes: a shaft having a proximal end and a distal end; a rotatory cord applicator at a location near the distal end, for securing a cord to the annulus of the valve; and means for cinching the cord to reduce the circumference of the valve. The shaft, for example, may comprise an elongate, handheld shaft. In some embodiments, the means for selectively advancing and securing the clips comprises a cable member coupled with the shaft. The cord may comprise any of a number of suitable materials or combinations of materials, including but not limited to a length of suture material, a length of Teflon strip, a wire, a band, and/or the like.
• In another aspect, a device for applying crimping clips to a heart valve annulus comprises: an elongate, handheld shaft having a proximal end and a distal end; a plurality of crimping clips carried by the shaft; and means for selectively advancing individual clips, securing the individual clips to the annulus, and crimping each individual clip to tighten at least a portion of the valve annulus. In some embodiments, the means for selectively advancing and securing the clips comprises a cable member coupled with the shaft. As mentioned above, these crimping clips may be either tethered or untethered. Thus, some embodiments further include a tether for connecting the plurality of clips for circumferentially tightening at least a portion of the valve annulus.
• In embodiments including a tether, the at least one actuator may include means for cinching the tethered clips to reduce the circumference of the valve annulus. In some embodiments, each of the plurality of crimping clips includes at least one eyelet, and the tether passes through the at least one eyelet of each clip. In some embodiments, each clip includes two eyelets, and the tether passes through both eyelets of each clip. In some embodiments, crimping the at least one eyelet of any of the plurality of clips such that a clip with a crimped eyelet is secured to the tether. More generally, any of the various features described above may be suitably used with tethered or untethered crimping clips in various embodiments.
• The present invention still further provides devices for applying tethered clips to an annulus, where the device includes a shaft, a tether, a plurality of clips, and a clip applier at or near a distal end of the shaft. In particular, the tether will have at least two parallel segments, where the segments may be separate or may be simply two ends of a tether which has been folded over itself. The clips slidably receive both segments of the tether, where the clips are arranged successively on the tether. The clip applier is adapted to secure the clips individually and usually successively to the annulus while the clips remain on the tether. The use of the tether having at least one additional segment is beneficial since it provides a redundancy, i.e., if either of the segments is severed or compromised, the other remains. Moreover, in the specific embodiments, each of the clips includes at least one eyelet for receiving the tethers, preferably including two eyelets so that each segment is received in a separate eyelet. The portion of the clips surrounding the eyelets will preferably be deformable to provide for crimping of both eyelets around both tether segments, again providing for redundancy.
• Apparatus according to the present invention still further includes an annular fastener. The annular fastener comprises a tether and a plurality of clips on the tether. The tether includes at least a pair of parallel segments, generally as described above, and the clips include a pair of spaced-apart eyelets, where one tether segment is received in each of the eyelets on each clip. Usually, a terminal clip will be provided on the fastener, where the terminal clip is fixed to a leading end of the tether, and may or may not include two eyelets. Usually, there will be at least two clips on the tether, more usually at least ten clips, often at least 15 clips, and sometimes as many as 30 or more. Additionally, at least a portion of the clips will be deformable in the region to permit crimping.
• The present invention also provides systems comprising any of the clip delivery devices described herein. In a first instance, the system comprises a clip applier device in combination with a stabilization device which is adapted to capture and immobilize the target valve or other annulus. Typically, the stabilization device comprises a pair of rings which are adapted to clamp opposed faces of the annulus. More typically, the clamps will be adapted to clamp over and under a heart valve annulus.
• Alternatively, systems according to the present invention may comprise any of the clip delivery devices in combination with a visualization device adapted to directly view a valve annulus in a heart chamber. The visualization device may comprise an ultrasonic imaging transducer, but will more typically comprise an optical viewing element disposed in a transparent element. Usually, the optical viewing element is a fiberoptic scope or a CCD, and the transparent viewing element comprises a transparent balloon inflatable with a transparent inflation medium.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a side view of the left side of an upper body of a patient, showing an incision and a device for mitral valve repair in accordance with an embodiment of the invention.
• FIG. 2A is a cut-away view of a heart, viewed from the base of the heart, with the atria cut away to view the valves, and a device for mitral valve repair in accordance with an embodiment of the invention.
• FIG. 2B is a perspective view of a distal end of a device for mitral valve repair in accordance with an embodiment of the present invention.
• FIG. 2C is a perspective view of multiple tethered clips according to an embodiment of the present invention.
• FIG. 3A is a top view of a mitral valve, with several clips placed in the mitral valve annulus, and a device for mitral valve repair in accordance with an embodiment of the invention.
• FIG. 3B is a top view of the mitral valve ofFIG. 3A, with clips in place along the length of the mitral valve annulus.
• FIG. 3C is a top view of the mitral valve of FIGS.3A-B, with clips in place along the length of the mitral valve annulus and with suture connecting and tightening the clips to reduce the circumference of the annulus.
• FIG. 3D is a schematic illustration of a heart valve stabilization device which may be used in the methods of the present invention.
• FIG. 3E is a schematic illustration showing where the atrial clamp and ventricular clamp of the stabilization ofFIG. 3D will be located on a mitral valve annulus.
• FIG. 3F illustrates an exemplary clip of the present invention which has been secured in a mitral valve annulus using the stabilization device ofFIGS. 3D and 3E.
• FIG. 3G illustrates an alternative construction for a stabilization device, where the atrial ring comprises a mechanism for delivering clips to the valve annulus while the valve remains stabilized with the stabilization device.
• FIG. 4A is a perspective view of an instrument introduction device for introducing a device through a heart wall in accordance with an embodiment of the invention.
• FIG. 4B is a perspective view of an instrument introduction device as inFIG. 4A in position in a section of a heart wall, with an instrument in place in accordance with an embodiment of the invention.
• FIG. 5A is a perspective view of a heart with a small incision in the wall of the left atrium.
• FIG. 5B is a perspective view of a heart as inFIG. 5A, with an instrument introduction device through the wall and an instrument placed through the device in accordance with one embodiment of the invention.
• FIG. 6 is a perspective view of a device for treating a heart valve in accordance with an embodiment of the present invention.
• FIG. 7A is a side view of a distal end of a heart valve treatment device having an attached ultrasound transducer as in an embodiment of the present invention.
• FIG. 7B is a side view of an ultrasound transducer and a gel-filled cone for enhancing ultrasound visualization in accordance with one embodiment of the present invention.
• FIG. 7C illustrates an optical viewing device useful in the methods of the present invention and comprising a fiberoptic scope.
• FIG. 7D is an enlarged view of the distal end of the device ofFIG. 7C, shown with the optical viewing scope in position within an optically transparent balloon.
• FIG. 8 is a perspective view of clips and a tether in accordance with one embodiment of the present invention.
• FIG. 9 is a side view of a surgical device for repairing a cardiovascular valve according to one embodiment of the present invention.
• FIGS. 10A and 10B are perspective views of a crimping clip and a tether in accordance with one embodiment of the present invention.
• FIG. 11 is a perspective view of a distal end of a surgical device according to one embodiment of the present invention.
• FIG. 11A is a close-up view of the distal end assembly of the device shown inFIG. 11.
• FIG. 12 is a perspective view of a distal end assembly of a surgical device in the process of closing a clip, according to one embodiment of the present invention.
• FIG. 12A is a perspective view of a distal end assembly as inFIG. 12, shown after closing the clip and in the process of retracting according to one embodiment of the present invention.
• FIG. 13 is a top, sectional view of a distal end assembly of a surgical device in the process of advancing a clip, according to one embodiment of the present invention.
• FIG. 14 is a transverse sectional view of a portion of a distal end assembly of a surgical device, according to one embodiment of the present invention.
• FIG. 15 is a side, sectional view of a distal end assembly of a surgical device in the process of dispensing a clip from a retainer of the device into a nose piece of the device, according to one embodiment of the present invention.
• FIG. 16 is a side, sectional view of a portion of a distal end assembly of a surgical device showing multiple clips in the retainer of the device, according to one embodiment of the present invention.
• FIG. 17 is a side view of the inside of the shaft of a distal end assembly of a surgical device showing a longitudinally stacked clip design, according to one embodiment of the present invention.
• FIG. 18 is a side view of the inside of the shaft of a distal end assembly of a surgical device showing a longitudinally stacked clip design, according to one embodiment of the present invention.
• FIG. 19 is a perspective view of the inside of the shaft of a distal end assembly of a surgical device showing a longitudinally stacked clip design, according to one embodiment of the present invention.
• FIG. 20 is a perspective view of a distal end assembly of a surgical device showing a transversely stacked clip design, according to one embodiment of the present invention.
• FIG. 21 is a side, sectional view of a distal end assembly of a surgical device showing a transversely stacked clip design, according to one embodiment of the present invention.
• FIG. 22 is a perspective view of the inside of the shaft of a distal end assembly of a surgical device showing a transversely stacked clip design, according to one embodiment of the present invention.
• FIG. 23 is a perspective view of a distal end assembly of a surgical device showing a clip crimping feature of the device, according to one embodiment of the present invention.
• FIG. 24 is a side view of a distal end assembly of a surgical device showing a tether cutting feature of the device, according to one embodiment of the present invention.
• FIGS. 25 and 26 illustrate a surgical device employing the clip advance and deployment mechanism ofFIGS. 11-24 together with a tether tensioning mechanism.
DETAILED DESCRIPTION OF THE INVENTION
• Generally, the present invention provides methods and devices for repairing a heart valve, such as the mitral valve, to treat heart valve regurgitation or insufficiency. Although the following description focuses on the treatment of mitral valves, various embodiments may be used to treat other cardiovascular valves, such as tricuspid, aortic and/or pulmonary valves. Furthermore, various embodiments of devices and methods of the invention may be used in open heart surgical procedures, minimally invasive surgical procedures, or both. Although minimally invasive valve repair may be advantageous in some circumstances, in other cases it may be advantageous to perform an open procedure. If the heart is to be stopped, for example, it may be advantageous to perform an open procedure to reduce the amount of time the patient is placed on cardiopulmonary bypass. The devices and methods of the invention themselves may also reduce the overall duration of a valve repair procedure, thus reducing the time the patient is on cardiopulmonary bypass.
• Generally, devices and methods of the invention involve coupling one or more devices with a valve annulus and using the devices to reduce the circumference of the annulus to reduce valve regurgitation. In some embodiments, methods involve securing a flexible cord about at least a portion of the annulus of the valve and cinching the flexible cord to reduce the annular circumference. Some embodiments, for example, involve placing multiple tethered anchoring devices into the mitral valve annulus. The tether is then tightened, applying force to the anchoring devices, to reduce the circumference of the mitral valve annulus. In some embodiments, clips may be crimped to reduce the annular circumference. Such crimping clips may be used with or without a tether in various embodiments. In other embodiments, a tethering device such as a rotatory cord may be applied to a valve annulus to tighten the annulus. Other embodiments may involve one or more other suitable techniques. Therefore, the following description is provided for descriptive purposes only and should not be interpreted to limit the scope of the invention as set forth in the claims.
• Referring now toFIG. 1, apatient10 undergoing valve repair according to various embodiments of the invention may require neither cardiopulmonary bypass nor a large skin incision. In other embodiments, an open heart surgical procedure, cardiopulmonary bypass or both may be employed. In some embodiments, an endotracheal tube may be used to ventilate patient10 (not shown) while allowing the patient's left lung to collapse to allow better access to the heart. Asmall incision14 may be made in the left thorax of the patient, to admit a mitralvalve repair device16. In one embodiment, for example, an incision of between about 0.5 and about 5 inches, and preferably between about 1 and about 3 inches, may be made in the fifth intercostal space ofpatient10. Any other minimally invasive incisions may alternatively be used in various embodiments. In other embodiments, any suitable open heart surgical incisions and procedures may be used, either on a beating heart or on a stopped heart using cardiopulmonary bypass. Alternatively, some devices and methods may be used intravascularly.
• At any suitable time before or during a mitral valve repair procedure, an imaging device may be placed in or on the patient to monitor the progress of the procedure. For example, in some embodiments a 3-dimensional, transesophageal echocardiogram device and/or a fluoroscopic C-arm may be used for visualization. After a skin incision is made, one or more various devices may then be used to navigate a path between the skin incision and the patient's heart. For example, an imaging devices such as an angioscope, as well as cutting and/or suturing devices may be used. Cutting and/or suturing devices may then be used to make a small incision in the left atrium, for example at the left atrial appendage. In one embodiment, an incision and a purse string suture will be used to gain access to the left atrium. Any suitable access methods or devices may be used, however, to gain surgical access to the mitral valve (or other valve to be repaired). As noted briefly above, methods of the present invention may typically be performed on a beating heart, thus eliminating the need for cardiopulmonary bypass. It is contemplated, however, that many embodiments will also be suitable for use in open-heart surgery techniques and/or in conjunction with use of cardiopulmonary bypass.
• In some embodiments,repair device16 will then be advanced into the left atrium through the incision, purse string suture, or other access site. In other embodiments, as described further below, an instrument introduction device may be inserted into the incision in the heart wall and may be secured to the wall, such as with suture material. At or near the distal end ofrepair device16, one or more repair actuators (not shown inFIG. 1) will be used to repair the mitral valve. For example, in various embodiments, repair actuators may include a device for applying a cord to a valve annulus, such as a rotatory device for applying a cord such as a suture or Teflon strip. A repair actuator may also include a suture cutter, a suture tightening device, a clip application device, a fastener application device, an imaging device, or any other suitable device or combination thereof.
• In many embodiments, the repair actuators will be generally configured to attach one or more fasteners to the mitral valve annulus and to tighten the fasteners to cinch, or tighten, the mitral valve annulus, thus decreasing the overall circumference of the mitral valve and reducing mitral regurgitation. In other embodiments, however, a fastener or other device may be placed across the valve, a device may be placed to bolster or increase the bulk of the valve annulus, or the like. Therefore, the invention is in no way limited to including fasteners, sutures, or the like.
• Referring now toFIG. 2A,repair device16 is shown in relation to a cross-section of aheart20.Heart20 is viewed from the perspective of the base of the heart (roughly, the top or cephalic part of the heart), as if the right and left atria were removed. The pulmonary26, aortic28, tricuspid24 and mitral22 valves are shown, as well as themitral valve annulus21 and the anterior commisure23 andposterior commisure25 ofmitral valve22.
• Repair device16 suitably includes anelongate shaft32, aproximal actuator27, and several distal repair actuators. In one embodiment, as shown more clearly inFIG. 2B, repair actuators include aclip applicator31, a series ofclips34 connected by atether36, arivet35 also connected to tether36, and arivet holder37. As already discussed,repair device16 may include more, fewer, or different distal repair actuators in various embodiments, without departing from the scope of the invention. Further discussion of the distal features of one embodiment ofrepair device16 are discussed further below in relation toFIGS. 11-25. Furthermore, any parts of repair device or devices to be used in mitral valve repair may be made radiopaque to facilitate imaging.
• As shown inFIG. 2B,elongate shaft32 may include a bent or otherwise shaped portion near its distal end.Repair device16 may also comprise any suitable means for applyingclips34, such asclip applicator31 in the form of an adjustable jaw. In some embodiments,elongate shaft32 includes a lumen for containingclips34,tether36 and/or other elements for applying or cinchingclips34 or the like.
• Referring now toFIG. 2C,repair device16 may generally be configured to hold a plurality ofclips34, for example withinshaft32. In some embodiments, for example, clips34 may be housed in a cartridge-like configuration which may fit withinelongate shaft32.Clips34 may be made of any suitable material, such as Nitinol™ (NiTi), stainless steel, titanium, or the like. Additionally, clips34 may have any suitable configuration and size for attaching to a portion of the mitral valve such as the mitral valve annulus. Although V-shaped, hingedclips36 with prongs are shown, U-shaped clips, T-shaped clips, multiply-bent clips, straight clips and/or the like may be used in various embodiments. In some embodiments, at least the mostdistal clip34n, typically a first clip to be placed invalve annulus21, may be coupled with an end oftether36. More than one clip may be coupled as well, in various embodiments. Coupling of one ormore clips34 withtether36 may be accomplished by any suitable means. In one embodiment, for example, aradiopaque tether anchor39 is used to anchortether36 to afirst clip34. In other embodiments, attachment may be made with adhesive, solder, knotting of the tether or the like.Subsequent clips34 are then typically suspended ontether36. Theclips34 may be attached to tether36 of may be freely suspended thereon.
• In some embodiments, clips34 will be configured as double-clips or crimping clips. Such crimping clips, for example may be configured similarly to two V-shaped clips, connected together at the bottom of the V. Each crimping clip may be attached to valve annulus tissue at two locations, adjacent to one another, and the clip may be crimped, to squeeze, pinch, or pleat annular tissue within the clip. Thus, multiple crimping clips may be applied circumferentially to an annulus to crimp, or tighten, tissue along the annulus, thereby tightening the annulus and reducing regurgitation. In some embodiments, such crimping clips will be used without a tether, while in other embodiments they will be coupled with a tether to provide for further annulus tightening. As withclips34 described above, such crimping clips may have any suitable size, shape and configuration and are not limited to V-shaped double clips.
• Tether36 generally runs between afirst clip34, or a device coupled withfirst clip34, through each of a plurality ofsubsequent clips34, to rivet35.Tether36 may be coupled with each clip by any suitable means. For example, inFIG.2B tether36 runs through a hole or eye in eachclip34. In other embodiments,tether36 may be tied, attached with adhesive, wrapped, or otherwise attached to each clip. Generally,repair device16 will be configured to placesuccessive clips34 along amitral valve annulus21, attaching eachclip34 to the annulus, for example by usingclip applicator31. Thus, after oneclip34 is attached, anotherclip34 will be fed or will naturally fall or otherwise be positioned withinclip applicator31 for application to the valve annulus.
• Tether36, which couples clips34 and rivet35 together may be any suitable substance for coupling and/or tightening multiple fastening devices. For example, in someembodiments tether36 will be conventional, durable suture material, having a diameter between about 1 mm and about 3 mm, and preferably about 2 mm. In other embodiments, a pre-shaped Teflon strip having a diameter between about 1 mm and about 6 mm, and preferably between about 2 mm and about 5 mm, may be used. Those skilled in the art will recognize that any suitable suturing, coupling, tensioning or similar devices may be used to tether and/or add tension between clips34.
• With continued reference toFIG. 2C, in some embodiments, a second tether anchor is coupled withtether36 and clips34 to better allow tether to be cinched. In one embodiment, second tether anchor comprises arivet35, ormultiple rivets35.Rivet35 is positioned near the proximal end ofclips34, whilefirst tether anchor39 is positioned near the distal end.Rivet35, for example, may include a hollow bore, through whichtether36 runs, and may be positioned to fit within one or moreproximal clips34a-b. In some embodiments, crimpingproximal clips34a-bto attach them to a valve annulus will also close theclips34a-baround rivet35 to securerivet35 to tether. For example, in one embodiment allclips34 other thanproximal clips34a-bwill be secured to a valve annulus.Tether36 will then be cinched, by applying tensile force to tether36 in a proximal direction (arrows). Once a desired amount of cinching force is achieved,proximal clips34a-bmay be crimped to securetether36 withinrivet35 and to secureproximal clips34a-boverrivet35 and to the valve annulus. In various embodiments, rivet35 may be preloaded or pre-inserted into one or moreproximal clips34a-b. In other embodiments, rivet35 may be moved into contact with proximal clip(s)34a-b, by an advancing device or the like. In still other embodiments, anysuitable rivet holder37 may be used to hold andplace rivet35 to allowrivet35 to act as a tether anchor. In one embodiment, forexample rivet holder37 may be a simple arm-like device. In other embodiments,rivet holder37 may be a forceps-like device used to place andrelease rivet35 at a desired location.
• Generally,tether36 may be coupled with eachclip34 or other attachment device, and withrivet35, and one end oftether36 then runs proximally back towardsproximal actuator27. In one embodiment, an end oftether36 runs throughshaft32 ofrepair device16 to a location at or near handle, so that a surgeon or other physician using the device may use thetether36 to apply force or tension toclips34,rivet35 and the like. In other embodiments, other suitable tethering and/or tightening devices may be used.
• With reference toFIG. 8, another embodiment of aclip100 andtether104 is shown. In some embodiments, clips100 may include two ormore eyelets102, rather than only one eyelet. In such embodiments,tether104 may run through both eyelets on eachclip100. In one embodiment,tether104 runs through oneeyelet102 of eachclip100, forms a loop around the far end of the first (or most distal)clip100a, and a parallel segment then runs back through theother eyelet102 of eachclip100. In some versions, both ends oftether104 may then be pulled proximally to cinch the tethered clips100. In general, tethering each clip through two or more eyelets may be advantageously stronger and more durable that tethering each clip through one eyelet. In alternative embodiments, various forms of securing devices may also be used, such as a washer or dowel-like securing device around tether to run througheyelets102 of thefirst clip100a. Furthermore,tether104 may be secured at or around afirst clip100aor other clips via any suitable means. For example, two tethers may be tied distal to thefirst clip100aor the like.
• With reference now toFIGS. 10A-10B, some embodiments include one or more crimpingclips120. Crimpingclips120 may be used in some embodiments withtethers124 and in other embodiments without tethers. In some embodiments, for example, atether124 may run through twoeyelets122 on each crimpingclip120. In anuncrimped clip120, as shown inFIG. 10A,tether124 passes relatively freely througheyelets122. Thus, for example,tether124 may be pulled througheyelets122 of theuncrimped clip120 to cinch multiple clips to help reduce the diameter of the valve annulus. When desired, such as after cinching,clip120 can be crimped, as shown inFIG. 10B. Crimpingclip120 involves deflectingeyelets122 is some way so as to reduce their inner diameter. In some embodiments, for example, a surgical device for placing crimpingclips120 includes a pusher, bar or other device for pressing a portion ofclip120 to depress or deflecteyelets122. When the inner diameter ofeyelets122 is reduced, theeyelets122 will tend to trap orsecure tether124 inside the inner diameter, thus securingtether124 in place. Thus, crimpingclips120 may be secured to a valve annulus and further secured to tether124 via crimping. Many other suitable configurations, shapes, sizes and the like are contemplated for crimping clips other than those shown inFIGS. 10A-10B.
• Referring again toFIG. 2A,proximal actuator27 ofrepair device16 generally includes any suitable device (or devices) for manipulating and actuating the distal repair actuators.Proximal actuator27 generally allows a surgeon or other physician to manipulaterepair device16 and activate one or more of the distal features to perform a procedure. In one embodiment,proximal actuator27 includes two or more gripper devices that act like a scissor mechanism. Alternatively, otherproximal actuators27 may include a trigger, a handle, a plunger, a squeeze-activated device, a syringe-grip device and/or any other device for moving and activating distal features/actuators ofdevice16. In some embodiments,proximal actuator27 may include a tether holder, tether cinching means, a clip adjuster, attachment for an imaging device and/or the like.
• Referring toFIG. 9, for example, an alternative embodiment of asurgical device110 is shown, having a distal end with means for applying aclip100 and a proximal end comprising ahandle113 and atrigger112.Trigger112 may be moved proximally (arrow) to perform a function, such as advancing and/or applying aclip100. Alternatively, trigger112 and handle may be replaced by a thumb- or finger-activated plunger device, a syringe-grip type device, a squeeze-activated device, or any other device or combination. Generally, any suitable proximal actuator is contemplated.
• Referring now toFIG. 3A, arepair device16 is shown applyingclips34 to amitral valve annulus21. In some embodiments, afirst clip34 may be placed and attached to thevalve annulus21 at or near the anterior commisure23 and subsequent clips may be placed and attached in a direction moving along theannulus21 towards theposterior commisure25. In other embodiments, it may be advantageous to start at or near the posterior commisure25 and move towards theanterior commisure23. In still other embodiments, clips34 may be started at a location apart from either commisure.
• FIG. 3B shows the same mitral valve with clips in place and attached to themitral valve annulus21 from theanterior commisure23 to theposterior commisure25. Furthermore, theclips34 are coupled withtether36 andrivet35 is coupled toclips34 viatether36. One end oftether36 is shown exiting themitral annulus21, clips34, and rivet35. Typically, this free end oftether36 would be contained withinrepair device16 and would be accessible for use in applying tensile force to tether36 in a proximal direction (arrows). For example, as explained above, the free end oftether36 may run through repair device to a location outsidepatient10, to allow a physician to apply tension to tether36.
• InFIG. 3C,tether36 has been used to apply tension (arrows) to and betweenclips34 to apply force tomitral annulus21. The force generated will generally be inwardly directed force, towards the center of themitral valve22, as is shown by arrows A. This force will also tend to pullclips34 towards one another, causing the circumference of themitral valve22 to decrease and, thus, helping to decrease mitral regurgitation. As mentioned above, in some embodiments it is possible to crimp one ormore clips34 before applying tension to tether36. Crimping may more securely attach aclip34 to the annulus, may secure aclip34 to tether36, or both.
• When the methods of the present invention are performed on beating hearts, either in minimally invasive procedures through ports or otherwise as described herein, or via an intravascular (closed chest) approach, it will be desirable to be able to stabilize and/or locate the valve annulus. It is important that the clips be applied to the fibrous tissue of the annulus and in particular that they not be delivered into the leaflet tissue or the tissue of the atrial wall, neither of which will provide the desired purchase for holding the clip. An exemplary method for achieving such stabilization utilizes a clamping device, such asdevice200 illustrated inFIG. 3D. Clampingdevice200 includes an upper oratrial ring202 and a lower orventricular ring204, typically adapted for placement above and below the annulus of the mitral valve. Therings202 and204 will typically be formed from an elastic material having a geometry selected to engage and optionally shape or constrict the valve annulus. For example, the rings may be formed from shape memory alloy, such as nitinol, from a spring stainless steel, or the like. In other instances, however, the rings could be formed from an inflatable or other structure can be selectively rigidized in situ, such as a gooseneck or lockable element shaft.
• Thedevice200 will be introduced to the left atrium of a beating heart, either transeptally or through an incision in the heart wall, as described hereinafter in connection with the clip appliers of the present invention. Once in the atrium, the lower or ventricular ring will be introduced through the mitral valve opening, with acorner206 of the ring typically being engaged against a commisure. Theventricular ring204 may be adjusted so that it lies at a junction between the valve leaflet L and the ventricular wall VW, as illustrated inFIG. 3E. The upper oratrial ring202 may then be clamped down onto the upper surface of the annulus VA, typically by sliding anouter shaft210 down over aninner shaft212. Thus, the annulus will be circumferentially clamped between the rings, again as observed inFIG. 3E. Such clamping will stabilize the annulus relative to the remainder of the beating heart, thus facilitating subsequent clip application. For example, the clip appliers described elsewhere herein may be used to introduceindividual clips156, as illustrated inFIG. 3F. Alternatively, theatrial stabilization ring202 could be replaced with acircular clip applier220, as shown inFIG. 3G. A stabilization device employing such a clip applier could be used to simultaneously stabilize the annulus and deliverclips222 using a clip driver, such as aballoon224.
• Although not illustrated, in some instances it may be desirable to provide a third stabilization element on the exterior of the heart, optionally between the coronary sinus CS and circumflex artery CF or within the coronary sinus.
• With reference now toFIG. 4A, some embodiments of the invention include aninstrument introduction device48 for facilitating introduction and manipulation of one or more instruments through a heart wall to perform a surgical procedure on a heart valve. In some embodiments, such adevice48 includes anouter surface52, aninner surface54, ahollow member56 coupled between the surfaces and avalve50 coupled withhollow member56. Generally,device48 may have any suitable size and configuration and may be made of any suitable material or combination of materials.Device48 is typically placed through a small incision on a heart wall, such thathollow member56 is disposed within the heart wall,outer surface52 is disposed on the outer surface of the heart wall, andinner surface54 is disposed on the inner surface of the heart wall.Valve50 comprises a one-way valve which allows one or more instruments to be introduced throughdevice48 into a heart chamber but which prevents blood from escaping out of the heart chamber throughvalve50.
• Referring now toFIG. 4B,instrument introduction device48 is shown within a section of aheart wall60 and with asurgical instrument58 extending throughvalve50 andhollow member56. In some embodiments,device48 may be removably attached toheart wall60 by a surgeon, for example by a purse-string suture or other means. Generally,device48 not only protects against blood loss during a surgical procedure but also reduces trauma toheart wall60 from manipulation ofsurgical instruments58. Thus,device48 and its various component parts may have any configuration, size and the like for achieving such effects in a heart valve surgery and any suitable configuration is contemplated. A suitable introduction device is described inco-pending application 60/462,502, the full disclosure of which is incorporated herein by reference.
• With reference now toFIG. 5A, aheart40 is shown from a left, side view, showing the outer surface of theleft ventricle44 and theatrium42. As shown, many methods of the invention may be performed via a minimallyinvasive incision46 in the left atrial wall. In some embodiments, as described above and as shown inFIG. 5B,instrument introduction device48 may be placed through theincision46, into a position within the wall of the heart. Oncedevice48 is in place, one or moresurgical instruments58 may be placed throughdevice48 to perform a surgical procedure. In fact,multiple instruments58 may be used one at a time, introducing each instrument throughdevice48 in some embodiments.
• With reference now toFIG. 6, one embodiment of adevice62 for performing minimally invasive heart valve repair suitably includes a thin, tubular,handheld shaft72, coupled at its proximal end with aconnector74 which in turn is coupled with anactuator76.Shaft72 may have any suitable shape, size and configuration to allow convenient manipulation ofdevice62 by a surgeon to perform a surgical valve procedure. In one embodiment, for example,shaft72 is shaped like a thin wand or pencil-like apparatus which may be held and manipulated with one hand of a surgeon and may be inserted into a chamber of the heart through a small, minimally invasive incision or introduction device.Shaft72 will typically be used to place and secure one or more tethering clips70 or other tethering devices in a valve annulus, such as the mitral valve annulus, and may also be used to cinch connected tethering devices to tighten the valve. In one embodiment, acable75 runs longitudinally through all or a part ofshaft72 and continues throughconnector74 or a similar housing toactuator76.Actuator76 may then act throughcable75 to advanceclips70 throughshaft72 and/or to applyclips70 to a valve annulus or other area on or around a valve. Thus, adevice62 as shown inFIG. 6 may includeshaft72 for manipulating and positioning with one hand of a surgeon and a coupledactuator76 for use by the other hand of the surgeon or by another person, such as an assistant. Athin shaft72 will typically be easy to manipulate and position, to enhance the accuracy and convenience valve surgery procedures.
• With reference now toFIG. 7A, asurgical device80 for surgically treating a heart valve may suitably include anultrasound transducer82 at or near the distal end of the device for enhancing visualization of avalve annulus83, other surgical site, surgical instruments and/or the like. For example,ultrasound transducer82 may comprise a distal tip which may be removably or permanently attached to the distal end ofsurgical device80. The embodiment inFIG. 7A also includesmultiple rivets81, which may be included to further enhance coupling of the tether and clips. In another embodiment,ultrasound transducer82 may be coupled withdevice80 near the distal end at a different location, may be permanently integrated intodevice80 and/or the like. Anysuitable ultrasound transducer82 may be used.
• In another embodiment, and with reference now toFIG. 7B, visualization of a heart valve surgical site and heart valve procedure may be enhanced by use of aconventional ultrasound transducer84 coupled with a gel-filled or fluid-filledcone86.Cone86 may have any suitable shape, size and overall configuration and may be filled, or partially filled, with any suitable gel or fluid for enhancing transmission of ultrasound signals fromtransducer84. Generally,transducer84 andcone86 may be coupled together via complementary coupling surfaces88 or any other suitable means. Oncetransducer84 andcone86 are coupled,cone86 may then be used to contact a surface of a heart to begin ultrasound visualization. The gel or fluid incone86 allows for efficient ultrasound transmission and visualization without requiring placement of gels or fluids directly onto heart tissue. Thus,ultrasound transducer84 may be used to effectively aid visualization of the heart without introducing unwanted gels, fluids, or the like into or onto the heart.
• Referring now toFIGS. 7C and 7D, in many instances it will be preferable to perform some or all of the interventional steps of the methods of the present invention under direct optical viewing. One apparatus for performing such direct optical viewing is thebubble scope250 illustrated inFIGS. 7C and 7D. Thescope250 includes asheath252, an inflatable, opticallytransparent balloon254 at a distal end of the sheath, afiberoptic scope256, an inflation tube orlumen258, ascope seal260, and aninflation port262 open to the interior of theballoon254.Scope256 is advanced distally through a lumen of thesheath252 so that the scope extends through theseal260, as illustrated inFIG. 7D. The seal around the scope permits inflation of the balloon through the inflation lumen, with an optically transparent medium entering through theinflation port262. The opticallytransparent balloon254 is preferably formed from an elastic material so that it can be engaged against the valve annulus or other interior cardiac surface and conform against said surface clip applier and other tools used in performing the methods of the present invention. Once in place inside the heart chamber, such as the left atrium above the mitral valve, theballoon254 may be engaged against a surface to be treated, against the distal end of the clip applier or both. Thebubble scope250 may thus be used to initially position the clip applier, optionally to observe the delivery of the clip, and finally to observe clip placement to confirm it is proper.
• Referring now toFIG. 11, adistal end140 of asurgical stapling device141 for repair of cardiovascular valves is shown. As mentioned above,distal end140 may have any of a variety of configurations, shapes, sizes, functions and the like in various embodiments of the invention. The following description, therefore, is provided for exemplary purposes only, to help describe one embodiment of a surgical device, and should not be interpreted to limit the scope of the invention as it is set forth in the claims.
• That being said, and with reference now toFIG. 11A, one embodiment of adistal end assembly140 suitably includes a distal end portion ofshaft142, ananvil144, atether146 havingparallel segments146aand146b, anose piece148, guideslots150, astaple mandrel152, aleaf spring154, one ormore staples156, and aretainer belt158. Again, other embodiments may include fewer or additional elements. Also, for the purposes of this description the terms “staple” and “clip” are interchangeable and generally refer to any fastener, anchor, or piece that may be attached to a valve. Generally, the features shown inFIG. 11A may be used to apply a plurality ofstaples156, tethered with one or more tethers orcables146, to a valve annulus. Tether146 may include but is not limited to a strip, band, filament, wire, strap or any other connective element. In one embodiment,staples156 are applied along the annulus of the a heart valve. One ormore tethers146 is pre-threaded through the eyelet (or eyelets) of each staple156 and runs from the distal end assembly ofdevice140 to the its proximal end.
• Oncestaples156 are secured to the tissue,tether146 is pulled from the proximal end ofdevice140 to cinchstaples156 and thereby reduce the annular diameter. Tension may be adjusted ontether146 while using ultrasound Doppler flow guidance or direct visualization in real time to allow the annulus to expand for precise adjustment of the annular correction. After an optimal size of the annulus is achieved, one or more final staples are dispensed and crimped (usingcrimp bar184 described with reference toFIG. 20) by the device. This step locks thetether146 tension by securing thetether146 to the final staple(s)156. Thetether146 is then cut at the point beyond the last staple by a sliding blade190 (FIG. 20) within the device or by any other suitable means.Shaft142, withnose piece148 and guide slots15, acts tolongitudinally guide staples156 toward the distal end assembly ofdevice140 to be applied to a valve annulus.Anvil144 pushesstaples156 forward/distally to be dispensed.
• Referring now toFIG. 12, a perspective view ofdistal end assembly140 is shown in the process of closing aclip156, withanvil144 pushingclip156 forward.FIG. 12A then showsdistal end assembly142 afterclip156 is closed, withanvil144 in the process of retracting. Generally, guide slots (not shown) along the length of the surgical device are continuous with the ramps and guideslots150 innose piece148. In operation, a user activates an proximal actuator (not shown) which drives a ratchet to rotate retainer belt158 (FIG. 15) such that a surface containing the set of staples translates distally. This activation of actuator also pushesanvil144 distally.
• Referring now toFIGS. 13 and 13A, retainer bumps160 onretainer belt158 contact generally fit aroundstaples156 and function to keepstaples156 in position while moving the staples distally. As the belt advances during the actuation process,staples156 are guided forward by theguide slots150 on each side of the inner diameter of the devices guideshaft157.
• Referring toFIG. 15, the mostdistal staple156 moves to the distal end, up aramp162, and is dispensed intoguide slots150 innose piece148 which are in continuity with the ramp and the guide slots in the device shaft.
• Once thedistal staple156 is moved intonose piece148,anvil144 moves forward (or distally) to movestaple156 distally until it bumps againststaple mandrel152 on the distal end of nose piece148 (FIG. 11A).Leaf spring154 generally pushes upward level with the top ofstaple mandrel152, but when an unclosed staple slides over them,leaf springs154 are deflected downward away from the top ofstaple mandrel152.Staple156 is retained within the plane ofguide slots150 innose piece148. In one embodiment, the inner surface of the distal end ofanvil144 is U shaped and the inner surfaces of the lateral prongs are curved outward. These outwardly curved lateral prongs act as ramps for the proximal-lateral aspect ofstaple156. Asanvil144 is advanced, the prongs can ramp over the lateral surfaces of the staple legs distally as well as inwardly (FIGS. 12 and 12A). The prongs bend the outer staple legs around the staple mandrel resulting in a closed staple as shown inFIGS. 12 and 12A. Oncestaple156 is closed, its lateral surfaces are not captured by the outside guide slot so it is and the staple is free to translate move transversely. As shown inFIG. 12A,anvil144 retracts when an actuation lever is released, and the leaf springs push staple156 up and out overstaple mandrel152.
• In one embodiment, as shown inFIGS. 17-19,staples156 are stacked longitudinally insideshaft142. Acompression spring166 pushes on acompression bloc164 to advancestaples156 forward as they are dispensed. The mostdistal staple156 is pushed through a staple dispensing opening170 (FIG. 18) by a staple dispensingpush plate168.
• In another embodiment, as shown inFIGS. 20-22,staples156 are stacked transversely.Staple guide slots150 in thenose piece148 allow onestaple156 to be pushed from the staple stack at a time. As the staples are used up, the stack decreases in height. Astaple stack spring180 maintainsstaples156 in position. Tether146 is threaded through the eyelets ofstaples156 and wraps around acable pulley182 so it can slide freely longitudinally as well as transversely through the stack ofstaples156. Free cable motion is important for making fine adjustments of cable tension throughstaples156 once they have been delivered to tissue. The free sliding of the cables through the undispensed staples also allows for newly dispensed staples to slide freely in position to be stapled to the tissue.
• Referring now toFIG. 23, afterstaples156 other than one or more final staples have been secured to tissue and cable tension and position have been adjusted (if necessary), one or morefinal staples156 are then dispensed and stapled to the tissue. In addition to bending the legs of thefinal staples156 inward to secure thefinal staples156 to annulus tissue, in one embodiment the eyelets of the final staples are crimped down tosecure cable146 to thefinal staples156. This crimping may be achieved by acrimp bar184, as shown inFIG. 23, which may be advanced forward (distally) to apply pressure against eyelets186 (or “holes”) of a clip. The pressure applied bycrimp bar184 closeseyelets186 to a degree sufficient to securetether146 withineyelets186, thus securingstaple156 to tether. In some embodiments,crimp bar184 is fitted within a central slot inanvil144. In closing the legs of non-termination staples,crimp bar184 is retracted in the central slot. To attach afinal staples156, a user activates a proximal actuator which drivescrimp bar184 to protrude forward. Alternatively, the switch may also be self-activated by the device when the final staple (or staples) is ready to be secured to tissue. Whenanvil144 advances to close the legs, the protrudingcrimp bar184 pressesstaple eyelets186 against the staple mandrel to crimp it tight on the cable to lock the cable to the staple.
• With reference now toFIG. 24, some embodiments of the device include acable cutter190 for cutting tether orcable146—once it is cinched to reduce the diameter of the valve. In some embodiments, once thefinal staple156 is applied, tension is applied to cable and staple eyelets are crimped, a switch (e.g., crank304 inFIG. 25) is activated to drive a spring loadedtether cutter190 forward to cutcable146. In other embodiments, a user may manually activatecutter190. Generally, any suitable means for cuttingcable146 may be used in the present invention.
• The various features ofdistal end assembly140 described above may be made from any suitable materials and combinations of materials. For example,nose piece148 andhousing142, in one embodiment, may be made from materials such as but not limited to stiff polymers such as polycarbonate, nylon, acrylonitrile butadiene styrene (ABS), polypropylene, PEEK, PVDF or urethane. In another embodiment,nose piece148 may be made from one or more stainless steel materials such as 17-4, 304, or 316 steel.Staple mandrel152,anvil144,crimp bar184, andcutter190 in one embodiment are made from a hard stainless steel such as hardened 17-4 steel and/or 440 steel. Alternatively, these features may be made from tungsten carbide or any other suitable material, such as softer stainless steels coated with titanium nitride to increase surface hardness. Leaf springs154 and compression springs166 in one embodiment may be made from a polymer like PEEK, nickel titanium, or stainless steel, but other materials may alternatively be used.Staple retainer belt158 may be made out of flexible polymers such as high flex PVDF, PTFE, nylons, polyethylene, polyurethane, polyester, isoprene, silicones and/or the like. Generally, any of these materials, combinations of these materials, or any other suitable materials or combinations not mentioned here may be used to manufacture one or more of the elements of a surgical device for repairing cardiovascular valves according to the invention.
• Anexemplary stapling device141 is illustrated inFIG. 25 where theshaft142 is connected to a pistolgrip handle assembly300. Theassembly300 includes atrigger302 for advancing and deployingindividual clips156 and optionally a crank304 for actuating the tether cutter190 (FIG. 24). Of particular interest, atether tensioning mechanism310 may be provided to take-up thetether segments146aand146b, as best seen inFIG. 26. The tensioning mechanism includes aspool312 which is mounted to spin freely to releasetether146 as the device dispenses the tether as thestaples156 are deployed. When desired, however, the mechanism can be switched to permit thetether146 to be “reeled” back over thespool312 to pull back and tension the deployed tether, i.e., to apply a constricting force to the staples surrounding the valve annulus. Usually, the mechanism will have a ratchet (not shown) to assist in manually turning of thespool312 to reel in the tether, and optionally the mechanism will include a tension control or measurement mechanism (not shown). Thus, immediately prior to crimping a terminal clip, thetether146 can be cinched to a preselected tension with the tensioning mechanism.
• Although the foregoing is a complete and accurate description of the present invention, it should be emphasized that the description provided above is for exemplary purposes only that variations may be made to the embodiments described without departing from the scope of the invention. For example, various embodiments of the invention may be used to repair a valve other than the mitral valve, such as the tricuspid valve. In other embodiments, clips may be eliminated and a rotatory cord such as a suture alone may be used. Other embodiments may include only a single, larger clip or fastener. Thus, the above scope of the invention as described in the appended claims.

Claims (36)

1. A device for applying tethered clips to an annulus, the device comprising:

a shaft having a proximal end and a distal end;

a plurality of clips slidably coupled to a tether, the tethered clips delivered by the shaft;

a clip applier at or near the distal end of the shaft for securing the clips to the annulus; and

at least one actuator at or near the proximal end of the shaft for causing the device to advance the clips and for activating the clip applier to secure the clips to the annulus.

2. A device as inclaim 1, wherein the clip applier comprises:

a pusher coupled with the actuator for advancing the clips; and

at least one slot in an inner surface of the shaft for guiding the clips.

3. A device as inclaim 2, wherein the clip applier further comprises a clip crimping member.

4. A device as inclaim 3, wherein the at least one actuator includes means for cinching the tethered clips to reduce the circumference of the valve annulus.

5. A device as inclaim 1, wherein the at least one actuator is selected from the group consisting of a trigger, a handle, a plunger, a squeeze-activated device, a syringe-grip device and a foot-operated device.

6. A device as inclaim 1, wherein each of the plurality of clips includes at least one eyelet, and the tether passes through the at least one eyelet of each clip.

7. A device as inclaim 6, wherein each of the plurality of clips includes two eyelets, and the tether has parallel segments passing through both eyelets of each clip.

8. A device as inclaim 6, farther comprising means for crimping the at least one eyelet of any of the plurality of clips such that a clip with a crimped eyelet is secured to the tether.

9. A device as inclaim 1, wherein the distal end of the shaft comprises a curved tip.

10. A device as inclaim 1, wherein the shaft is introducible into a patient through a minimally invasive incision.

11. A device as inclaim 1, further comprising a tether anchor coupled to the tether and carried by the shaft.

12. A device as inclaim 11, wherein the tether anchor comprises a rivet.

13. A device as inclaim 11, wherein the tether anchor is coupled with at least a last clip of the tethered clips such that crimping the last clip secures the last clip to the tether anchor and the tether anchor to the tether.

14. A device as inclaim 13, wherein the tether anchor is further coupled with a penultimate clip, such that crimping the penultimate clip secures the penultimate clip to the tether anchor and the tether anchor to the tether.

15. A device as inclaim 1, wherein the tether is selected from the group consisting of a suture material, a Teflon strip, a band, a filament, a wire and a strap.

16. A device for applying tethered clips to an annulus, the device comprising:

a shaft having a proximal end and a distal end,

a tether having at least two parallel segments;

a plurality of clips which slidably receive both segments of the tether, wherein said clips are arranged successively on said tether, and

a clip applier at or near the distal end of the shaft for securing clips to the annulus while said clips remain on said tether.

17. A device as inclaim 16, wherein the clips each include a pair of spaced-apart eyelets, wherein one segment is received in each eyelet of the pair.

18. A device as inclaim 17, wherein the clips are deformable in the region of the eyelets to permit crimping.

19. An annular fastener comprising:

a tether comprising first and second segments, and

a plurality of clips, each clip comprising first and second tether-receiving elements, wherein one segment is received in each of the tether-receiving elements on each clip.

20. An annular fastener as inclaim 19, further comprising a terminal clip which is fixed to a leading end of the tether.

21. An annular fastener as inclaim 19, wherein the plurality of clips includes at least three clips.

22. An annular fastener as inclaim 19, wherein the clips are deformable in the region of the tether-receiving elements to permit crimping.

23. A system comprising:

a device as inclaim 1; and

a stabilization device adapted to capture and immobilize the annulus relative to the remainder of the heart.

24. A system as inclaim 23, wherein the stabilization device comprises a pair of rings which are adapted to clamp opposed faces of the annular surface.

25. A system as inclaim 24, wherein the device is adapted to clamp over and under a heart valve annulus.

26. A system comprising:

a device as inclaim 16, and

a stabilization device adapted to capture and immobilize the annulus relative to the remainder of the heart.

27. A system as inclaim 26, wherein the stabilization device comprises a pair of rings which are adapted to clamp opposed faces of the annulus.

28. A system as inclaim 26, wherein the device is adapted to clamp over and under a heart valve annulus.

29. A system comprising:

a device as inclaim 1; and

a visualization device adapted to directly view a valve annulus in a heart chamber.

30. A system as inclaim 29, wherein the visualization device comprises an ultrasonic imaging transducer.

31. A system as inclaim 29, wherein the visualization device comprises an optical viewing element disposed in a transparent element.

32. A system as inclaim 31, wherein the transparent element comprises a transparent balloon inflatable with a transparent inflation medium.

33. A system comprising:

a device as inclaim 16; and

a visualization device adapted to directly view a valve annulus in a heart chamber.

34. A system as inclaim 33, wherein the visualization device comprises an ultrasonic imaging transducer.

35. A system as inclaim 33, wherein the visualization device comprises an optical viewing element disposed in a transparent element.

36. A system as inclaim 34, wherein the transparent viewing element comprises a transparent balloon inflatable with a transparent inflation medium.

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