US20040167539A1 - Mitral and tricuspid valve repair - Google Patents

Abstract

A novel approach to mitral or tricuspid valve repair involves the performance of an edge-to-edge fastening/securing of opposing heart valve leaflets through a catheter entering the heart. Thus, a device is introduced including a leaflet fastener applicator through a cardiac catheter or other suitable catheter. The leaflet fastener applicator and cardiac catheter can be formed into a kit. A gripper can be used to hold the heart valve leaflets while they are fastened.

Description

BACKGROUND OF THE INVENTION
• The invention relates to the repair of mitral and tricuspid valves exhibiting valve regurgitation. More particularly, the invention relates to apparatus and methods suitable for a less invasive repair of a mitral or tricuspid heart valve.[0001]
• Mitral regurgitation, i.e., backward leakage of blood at the mitral heart valve, results in reduced pumping efficiency. Furthermore, compensatory mechanisms such as hypertrophy and dilation of the ventricle suggest early treatment to prevent progressive deterioration of ventricular function. Diagnosis of mitral regurgitation can be performed using visualization with transesophageal echocardiography or by echocardiodiography. In particular, defective leaflet coaptation and the site and direction of the regurgitant flow can be examined to evaluate likely modes of failure.[0002]
• Mitral valve prolapse, i.e., myxomatous degeneration of mitral valve leaflets, is the most common cause of mitral regurgitation in North America. Rheumatic heart disease was the most common cause of mitral regurgitation in the U.S.A. thirty years ago and is still the most common cause of mitral regurgitation in developing countries. Chronic rheumatic heart disease results in retraction, deformity and rigidity of one or both mitral valve cusps as well as structural abnormalities in the commissures, chordae tendinae and papillary muscles. Ischemic mitral regurgitation (IMR), i.e., anemia of the valve tissue due to reduced arterial blood flow feeding the valve tissue, is the second most common cause of mitral valve regurgitation. Studies suggest that annular irregularities and posterior papillary muscle fibrosis with scarring of the underlying ventricular wall may be associated with IMR.[0003]
• Many cases of mitral regurgitation can be repaired by modifications of the original valve in a procedure generally referred to as valvuloplasty. These repair procedures typically involve a full sternotomy and quadrangular resection of the anterior leaflet, while on cardiopulmonary bypass. Repairs can also involve reattachment of chordae tendinae, which tether the valve leaflets, or removal of leaflet tissue to correct misshapen or enlarged valve leaflets. In some cases, the base of the valve is secured using an annuloplasty ring. Valves that are heavily calcified or significantly compromised by disease may need to be replaced.[0004]
• As an alternative to these repair techniques, an edge-to-edge suturing of the anterior and posterior mitral valve leaflets can be performed. Commonly referred to as a “bow-tie” repair, edge-to-edge suturing ensures leaflet coaptation without performing a quadrangular resection of the anterior leaflet. The bow-tie repair generally involves the use of a centrally located suture, although a suture can be placed close to a commissure, or multiple sutures can be used to complete the repair. A centrally placed suture creates a double orifice valve, which resembles a bow-tie.[0005]
• The bow-tie repair procedure has been applied using invasive procedures by placing the patient on extracorporeal circulation. An incision is made to provide access into the left atrium of the heart. Following suturing, the atrium is closed. Such repairs can result in a significant decrease in mitral regurgitation along with a corresponding increase in the ejection fraction.[0006]
SUMMARY OF THE INVENTION
• In a first aspect, the invention relates to a kit including a cardiac catheter and a leaflet fastener applicator. The cardiac catheter generally has suitable dimensions for deployment and insertion into a human heart in the vicinity of the mitral or tricuspid valve. The leaflet fastener applicator generally has a size allowing insertion through the cardiac catheter and is capable of holding portions of opposing heart valve leaflets.[0007]
• In another aspect, the invention relates to a method of repairing the mitral or tricuspid valve of a beating heart, the method including:[0008]
• a) inserting the distal end of a catheter into the heart to provide access to the valve; and[0009]
• b) fastening together portions of leaflets of the valve using a leaflet fastener applicator inserted through the catheter.[0010]
• In another aspect, the invention relates to a device including a catheter and a leaflet fastener applicator. The catheter has a proximal end, a distal end and suitable dimensions for insertion into a heart. The leaflet fastener applicator passes through the catheter such that an actuating element projects from the proximal end of the catheter while a fastening element projects from the distal end of the catheter.[0011]
• In another aspect, the invention relates to a heart valve leaflet fastener including two pairs of arms. Each pair of arms is of a suitable size for fastening heart valve leaflets together. The two pairs of arms are capable of fastening two adjacent leaflets.[0012]
• In another aspect, the invention relates to a heart valve gripper/fastener applicator including a gripper and a fastener applicator wherein the gripper and the fastener applicator extend from a single shaft.[0013]
• In another aspect, the invention relates to a heart valve leaflet fastener applicator including two opposing jaws. One of the jaws has a site for holding a tack, and the second jaw has a site for holding a cap.[0014]
• In another aspect, the invention relates to a gripper including a plunger that slides over an inner shaft, and arms having suitable dimensions for gripping heart valve leaflets. The plunger slides such that the interaction of heart valve leaflets with the plunger directs the leaflets toward the arms.[0015]
• In another aspect, the invention relates to a fastener applicator including a first shaft, a first portion of a button clip having a sharp projection for piercing a heart valve leaflet, a second shaft that slides over the first shaft, and a second portion of the button clip having an opening to engage the projection of the first portion of the button clip. The second portion of the button clip slides over the first shaft and not over the second shaft such that the second shaft can direct the second portion toward the first portion.[0016]
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a side view of one embodiment of a cardiac catheter.[0017]
• FIG. 2 is a perspective view of the proximal end of the cardiac catheter of FIG. 1.[0018]
• FIG. 3 is a side view of a suture knot securing two leaflets together.[0019]
• FIG. 4 is a side view of a knot pusher.[0020]
• FIG. 5 is a perspective view of sutured heart valve leaflets being secured with a suture clip with a portion of a cardiac catheter cut away to expose structure within the catheter.[0021]
• FIG. 6 is a perspective view of endoscopic scissors being used to cut a suture.[0022]
• FIG. 7 is a perspective view of heart valve leaflets secured with attached wires that have suture attached at one end.[0023]
• FIG. 8 is a side view of heart valve leaflets each pierced by a barbed needle where the barbed needles are attached to each other with suture.[0024]
• FIG. 9 is an enlarged view of a barbed needle of FIG. 8.[0025]
• FIG. 10 is a side view of a push rod useful for the deployment of the barbed needles of FIG. 8.[0026]
• FIG. 11 is a side view of barbed needles with flexible wire attached to the needle.[0027]
• FIG. 12 is a side view of heart valve leaflets with the barbed needles of FIG. 11 piercing the heart valve leaflets and a push rod gripping the suture connecting the two barbed needles.[0028]
• FIG. 13A is a side view of a fastener with a corresponding applicator inserted between two heart valve leaflets prior to deployment.[0029]
• FIG. 13B is a side view of the fastener and applicator of FIG. 13A with arms extended on either side of the heart valve leaflets.[0030]
• FIG. 13C is a side view of the fastener and applicator of FIG. 13 A where the arms are being pushed together to grab the leaflets.[0031]
• FIG. 13D is a side view of the fastener and applicator reaching a locked position where the leaflets are held firmly in place.[0032]
• FIG. 13E is a side view of the leaflets secured in place by the fastener of FIG. 13A after the applicator is removed.[0033]
• FIG. 13F is a sectional view of the engagement mechanism used to secure and detach the fastener of FIG. 13A from the applicator used to deploy the fastener.[0034]
• FIG. 14A is a perspective view of a gripper/fastener with spring loaded arms being deployed from a cardiac catheter with a portion of the cardiac catheter cut away to expose structure within the catheter.[0035]
• FIG. 14B is a perspective view of the gripper/fastener of FIG. 14A with two spring loaded arms being free of the cardiac catheter with a portion of the cardiac catheter cut away to expose structure within the catheter.[0036]
• FIG. 14C is a perspective view of the spring loaded fastener of FIG. 14A deployed holding heart valve leaflets following release of the deployment device with a portion of the cardiac catheter cut away to expose structure within the catheter.[0037]
• FIG. 14D is a perspective view of an alternative embodiment of the arms of the spring loaded fastener where the arms are curved.[0038]
• FIG. 15 is a side view of a needle fastener with a suction based gripper.[0039]
• FIG. 16 is side view of a gripper mounted adjacent a fastener applicator being directed toward heart valve leaflets.[0040]
• FIG. 17 is an enlarged perspective view of the gripper and fastener applicator of FIG. 16.[0041]
• FIG. 18A is a sectional side view of the gripper of FIG. 17.[0042]
• FIG. 18B is an exploded side view of an alternative embodiment of the gripper of FIG. 18A, the alternative embodiment being based on a cam, where the rod and moveable jaw have been removed from the remainder of the gripper.[0043]
• FIG. 18C is a side view of the embodiment shown in FIG. 18B.[0044]
• FIG. 18D is a view down the end of the shaft from the proximal end toward the jaws, where the ball of the cam is shown in both an open and closed position.[0045]
• Fiqs.[0046]19A-C are sectional views of the fastener applicator of FIG. 17 where the section in FIG. 19B is taken at a right angle relative to the sections in FIGS. 19A and 19C. Hidden structures are shown with phantom lines.
• FIG. 19D is a side view of the tack and cap of FIG. 19A secured together, shown in phantom.[0047]
• FIG. 20 is a side view of a gripper with a plunger used to direct the leaflets to gripper arms.[0048]
• FIG. 21 is a side view of an alternative embodiment of a gripper with spring loaded arms and a balloon plunger that directs the leaflets to the spring loaded arms.[0049]
• FIG. 22 is a side view of hooks used as gripper elements.[0050]
• FIG. 23 is a side view of a spring fastener with a suction based gripper.[0051]
• FIG. 24 is a side view of heart valve leaflets secured with a spring fastener of FIG. 23.[0052]
• FIG. 25 is a perspective view of a portion of a clip button held by a deployment device, the clip button being useful for fastening heart valve leaflets.[0053]
• FIG. 25A is a perspective view of the tip of a first applicator.[0054]
• FIG. 26 is a perspective view of the clip button of FIG. 25 and associated deployment devices, with the two portions of the clip button aligned.[0055]
• FIG. 27 is a front view of a first portion of the clip button of FIG. 26.[0056]
• FIG. 28 is a side view of the first portion of the clip button of FIG. 26.[0057]
• FIG. 29 is a side view of the second portion of the clip button of FIG. 26.[0058]
• FIG. 30 is a rear view of the second portion of the clip button of FIG. 26.[0059]
• FIG. 31 is a side view of the second portion of the clip button of FIG. 26 rotated[0060]90 degrees relative to the view in FIG. 29.
• FIG. 32 is a side view of the two portions of the clip button of FIG. 26 fastened together.[0061]
• FIG. 33 is a sectional side view of a spring loaded ring in a loaded position.[0062]
• FIG. 34 is a sectional side view of the spring loaded ring of FIG. 33 in an extended position.[0063]
• FIG. 35 is a side view of a crimp ring in an uncrimped position.[0064]
• FIG. 36 is a side view of the crimp ring of FIG. 35 following crimping.[0065]
• FIG. 37 is a perspective view of a ring fastener being positioned with an applicator toward heart valve leaflets, where a portion of the cardiac catheter is cut away to permit the visibility of structure within the catheter.[0066]
• FIG. 38 is a perspective view of the applicator of FIG. 37 following deployment of the ring fastener.[0067]
• FIG. 39 is a side view of one embodiment of an automatic suture device positioned near heart valve leaflets.[0068]
• FIG. 40 is a side view of the automatic suture device of FIG. 39 gripping the heart valve leaflets with needles.[0069]
• FIG. 41 is a sectional view of one of the needles of the automatic suture device of FIG. 39.[0070]
• FIG. 42 is sectional view of the automatic suture device of FIG. 39 with an ultrasonic welder positioned for placement at its ultimate welding position.[0071]
• FIG. 43 is a side view of an alternative embodiment of an automatic suture device.[0072]
• FIG. 44 is a perspective view of the automatic suture device of FIG. 43.[0073]
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• Methods have been developed for performing less invasive mitral valve repairs. While the discussion focuses on the repair of mitral heart valves, the repair approaches can be used for the repair of tricuspid valves using straightforward modification of the described procedures and instruments. In particular, the repairs can be performed on a beating heart such that the patient does not have to be placed on cardiopulmonary bypass.[0074]
• Access into the heart for mitral valve repair is obtained by securing a passageway from the exterior of the body into the body and into the heart to provide access into the left atrium or left ventricle. With suitable instruments inserted through the passageway, the mitral leaflets are grabbed, and the edges of the leaflets are secured together. The gripping and securing or fastening procedures can be performed simultaneously in some embodiments of the invention, or they can be performed separately. A suitable method of visualization may be used to guide the manipulations. Manipulations to the mitral valve can be conducted under ultrasound or fluoroscopy to show correct placement of the devices and of the repair and to verify effectiveness of the repair.[0075]
• One approach to introduce the instruments into the heart involves the direct introduction of a passageway through the wall of the heart. To introduce the passageway or a cardiac catheter into the body, a small incision is made in the chest. Instruments generally used to position catheters can be used to guide the cardiac catheter to the heart and into the heart wall, as described further below. Use of properly selected instruments for the introduction of the cardiac catheter reduces the amount of trauma to the heart. Upon completion of the mitral valve repair, the instruments are removed through the cardiac catheter, the cardiac catheter is removed, and the incision in the heart wall is repaired, for example, with suture.[0076]
• Alternatively, the instruments can be introduced into the heart by a vascular approach. In these approaches, a catheter is introduced into an artery or vein and directed into the heart. These vascular approaches are described further below.[0077]
• Suitable gripping and fastening instruments have appropriate dimensions to fit through the cardiac catheter into the heart. In general, the instruments have a tubular section or shaft between a distal end and a proximal end. The tubular section may be flexible. The distal end of the instrument is inserted through the cardiac catheter into the heart. The gripping and/or securing/fastening elements are located at the distal end of the instrument. One or more actuating elements are located at the proximal end.[0078]
• In some embodiments, a single element performs the gripping and fastening functions. In other words, a fastening element grips the tissue during the fastening process such that a separately identifiable gripping element is not present. For example, suture can be placed through each leaflet such that tightening of the suture draws the two portions of the leaflets together.[0079]
• Alternatively, the gripping and fastening elements can be distinct, separate instruments. For certain embodiments, functionally distinct gripping and fastening elements can be integrated into a single instrument such that a single tubular section is needed. Alternatively, the distinct gripping and fastening elements can be located on separate instruments, each having a separate tubular section. If the gripping and fastening elements are located on separate instruments, the tubular sections of the instruments can have suitable dimensions such that the two tubular sections can be inserted simultaneously through a single cardiac catheter. Alternatively, one or more additional cardiac catheters can be introduced into the heart to provide separate instrument passageways for the gripping and fastening instruments and any other instruments used to facilitate the procedure. Also, one or more additional cardiac catheters can be used to provide a means of direct visualization.[0080]
• Instruments[0081]
• The mitral valve repair device generally includes a gripper/fastener applicator instrument, and may include a cardiac catheter or other suitable catheter. The cardiac catheter generally has an elongated tubular section and proximal and distal ends each with an opening. For example, the cardiac catheter can be a catheter introducer used for standard intravascular placement or a similar instrument. An embodiment of a[0082]cardiac catheter126 is displayed in FIG. 1.Proximal end102 includesopening104, as shown in FIG. 2, through which a gripper/fastener applicator instrument is introduced.Proximal end102 preferably includes ahemostasis valve106 to prevent blood from flowing out of the cardiac catheter. Standard designs used in the catheter art can be used for the hemostasis valve.
• [0083]Tubular section108 of cardiac catheter100 preferably is flexible so that it can be guided through the body to the desired location. Generally,tubular section108 has a length from about 4 cm to about 15 cm and a diameter from about3 mm (9 French (F)) to about 10 mm (30 F), more preferably from about 3 mm (9 F) to about 8 mm (24 F). However,tubular section108 can be selected to have a suitable length appropriate for the specific procedure used.Tubular section108 preferably has atapered end110 to assist with introduction of cardiac catheter100 into the heart.
• The gripper/fastener applicator instrument can have one functional element that accomplishes both the gripping and fastening operations simultaneously (e.g., FIG. 19), or two functional elements with one element performing the gripping and a second performing the fastening (e.g., FIG. 17). Two functional elements can be integrated together on a single instrument, or they can operate together as two separate instruments through the cardiac catheter(s). One or more cardiac catheters can be used, as needed or desired. Specific embodiments are described below.[0084]
• A first type of gripper/fastener applicator has one functional device that accomplishes both gripping and fastening functions. Several embodiments of the first type of gripper/fastener applicator can be based on attachment of suture that is tied off to secure. the leaflets together.[0085]
• Referring to FIG. 3,[0086]sutures120 placed through therespective valve leaflets122,124 can be tied outside of the body.Sutures120 can be positioned using a needle or needles that are passed through leaflets and withdrawn throughcardiac catheter126. A knot pusher130 (FIG. 4) can be used to push a knot tied outside of the body to the leaflets such that the knot pulls the leaflets together. Variations on the design of the needle and the knot pusher can be used to accomplish the same purposes. Alternatively, rather than tying a knot, asuture clip132 can be used to fastensutures120, as shown in FIG. 5.Suture clip132 is pushed into place up toleaflets122,124 with aclip pusher134.Suture clip132 is shaped such that suture can be fed throughclip132 only in one direction. Oncesutures120 are tied or clipped,suture120 can be cut withendoscopic scissors136, as shown in FIG. 6, or other similar device.
• Another suture based gripper/fastener embodiment is depicted in FIG. 7. Instead of passing suture through each leaflet, the[0087]suture150 can be secured to the edge ofleaflets122,124 with a piece ofwire152 at one end ofsuture150.Wire152 can be sharpened spiral or coiled wire, such as a pacemaker lead.Wire152 can be crimped on the edge of aparticular leaflet122,124. As described above, the suture can be tied outside the heart, the knot can be pushed to the leaflets, and thesuture150 can be cut.
• Another embodiment of a single element gripper/fastener applicator involves the use of barbed needles. Referring to FIG. 8, a[0088]barbed needle200 penetrates eachleaflet122,124. If the repair requires further securing of the leaflets, additional needles may be deployed.Barbed needles200 are connected to each other bysuture206. Eachneedle200 can include a plurality of barbs208 (FIG. 9).Barbed needles200 can be deployed individually with a push rod210 (FIG. 10). Pushrod210 generally hasreleasable jaws212 for holdingbarbed needles200 during deployment.Jaws212 are activated bylever214 at thehandle end216 ofpush rod210. Alternatively, suitable push rods or other mechanical trigger actuators, such as spring activated mechanisms, can be used to deploybarbed needles200.
• In order to use a short enough piece of[0089]suture206 to hold the leaflets closed while having enough flexibility to deploybarbed needles200, the embodiment in FIG. 8 can be modified as shown in FIG. 11. Eachbarbed needle222 has awire224 extending fromneedle222.Suture226 connects the twowires224.Barbed needles222 can be deployed in the same way as depicted in FIG. 8. Referring to FIG. 12,push rod210 withjaws212 or a similar device can be passed into the heart throughcardiac catheter126 to grabsuture226. Pushrod210 is rotated to windsuture226 and ultimately to windwires224. The winding ofwires224 drawsbarbed needles222 closer together, resulting inleaflets122,124 being drawn closer together.Wires224 preferably are made of material, such as stainless steel, which is malleable enough that they can be wound together with forces transmitted through the suture yet resilient enough that the wires do not unwind from the load transmitted byleaflets122,124.
• Alternatively, suture can be connected directly to each barbed needle and looped around the other needle. Pulling each suture then draws each barb to the other. Additional knots can be pushed down from outside the body through[0090]cardiac catheter126 to secure the two sutures together.
• In other embodiments of a single element gripper/fastener applicator, a gripping/fastener applicator device is deployed and later released using an applicator. For example, referring to FIG. 13A, a deploying[0091]wand250 is inserted throughcardiac catheter126.Outer sleeve254 holdsgripper arms256,258,260,262 in place againstinner core264. Deployingwand250 is inserted betweenleaflets122,124. Referring to FIG. 13B,outer sleeve254 is pulled away fromgripper arms256,258,260,262 to permit gripper arms to extend once theouter sleeve254 no longer holds them in place.
• With[0092]gripper arms256,258,260,262 extending on both side ofleaflets122,124,inner core264 is pulled inward andouter sleeve254 is pushed outward in the direction of arrow266 (FIG. 13C), such that arms are being pushed together to grab the leaflets. Referring to FIG. 13D,gripper arms256,258,260,262 holdleaflets122,124 in place. The position ofgripper arms256,258,260,262 alonginner core264 is locked in place by stops270.Gripper arms256,258,260,262 are extended beyond an equilibrium position such that restorative forces tend to pull gripper arms towardinner core264. Referring to FIG. 13E, end272 ofinner core264, while gripping andfastening leaflets122,124, is released from the remaining portions ofinner core264 by disengaging a locking mechanism thereby securing the leaflets with the fastening device.Inner core264 is removed throughcardiac catheter126. The locking mechanism can have any of a variety of conventional structures, so as to grip and fastenleaflets122,124. One embodiment of a suitable locking mechanism is depicted in FIG. 13F. Pivoting latches280 lock intoflanges282.Wires284 can be used to releaselatches280 fromflanges282.Gripper arms256,258,260,262 generally have a length from about 2 mm to about 10 mm.Inner core264 generally has a diameter from about 1 mm to about 8 mm.
• A similar embodiment of the invention is depicted in FIG. 14. In single element gripper/[0093]fastener applicator300,arms302,304,306,308 are spring loaded. Asarms302,304,306,308 are pushed free of theend310 of cardiac catheter126., they extend due to the spring loading feature. In FIG. 14B, gripper/fastener applicator300 is depicted witharms302,306 extended.Arms302,306 have pointedtips314,316 that can pierceleaflets122,124. As depicted in FIG. 14C, oncearms304,308 are free of thecardiac catheter126,arms304,308 extend on one side of the leaflets to graspleaflets122,124 along witharms302,306, which extend on the other side ofleaflets122,124.Arms304,308 haveclasps322,324 that engage pointedtips314,316 such thatarms302,304,306,308 firmly graspleaflets122,124 therebetween. Grasper/fastener applicator300 is released fromapplicator326 by rotatingknob328 such thatknob328 passes throughpassageway330 withinbase332. In an alternative embodiment,arms302,304,306,308 are curved as depicted in FIG. 14D.
• The second type of gripper/fastener applicator has two distinct elements, a gripper element and a fastener applicator element. The gripper element and the fastener applicator element can be located at the respective distal ends of two distinct shafts. For certain embodiments the gripper element and the fastener applicator elements can be integrated on a single shaft and may be adapted to move relative to one another as appropriate for the procedure that is being performed, i.e., gripping or fastening. In this way, a single shaft can be guided through the cardiac catheter.[0094]
• An embodiment of a distinct gripper and a fastener applicator integrated onto a single shaft is depicted in FIG. 15. Gripper/[0095]fastener applicator340 has aspiral needle342, which spirals aroundinner catheter344. The first step involves applying suction through an internal lumen ofinner catheter344 by way of openings346 to grasp and position a leaflet againstinner catheter344. Once the leaflets are grasped by suction,spiral needle342 is advanced and rotated. Rotation of outer sleeve343 results in the passage ofspiral needle342 throughleaflets122,124.Spiral needle342 is mounted on outer sleeve343 that rotates aroundinner catheter344. The outer sleeve can be threaded to provide appropriate pitch and number of rotations. To hold the leaflets in place,spiral needle342 is disengaged from outer sleeve343 by disengaging a clamp or the like at theend345 of outer sleeve343. If desired, the needle can be crimped to ensure permanent attachment. The suction based gripper of FIG. 15 can be used also with other types of fasteners.
• Referring to FIGS.[0096]16-17,device400 includes agripper402 and afastener applicator404 that extend from ashaft406.Gripper402 andfastener applicator404 can be adjacent each other, as shown in FIG. 17. Alternatively,gripper402 andfastener applicator404 may move relative to each other by sliding in a tube, track, or similar mechanisms. The relative position ofgripper402 andfastener applicator404 can be reversed. In FIG. 17, withfastener applicator404 in a distal withdrawn position,gripper402 can grableaflets122,124. Then,fastener applicator404 can be opened in the withdrawn position and slid forward to apply a tack on captured leaflet edges. Therefore,gripper402 preferably is oriented relative toleaflets122,124 as shown in FIG. 16.
• One embodiment of[0097]gripper402 is depicted in FIG. 18A. In this embodiment,claw gripper412 has opposingjaws414,416, which meet atserrated edges418,420 in a closed orientation.Serrated edges418,420 assist with the gripping of theleaflets122,124. The extension ofrod422 alters the relative position ofjaws414,416 by moving alever424.Rod422 extends throughshaft406 to the distal end ofshaft406 such that a physician can manipulaterod422 outside of the patient. The length ofjaws414,416 should be appropriate for the jaws to reachleaflets122,124 at the maximum anticipated spacing betweenleaflets122,124. If desired,grippers412 can be used with a shaft separate from a shaft holding a fastener applicator element.Grippers412 are designed to gripleaflets122,124 as depicted in FIGS. 16, 17 and18.
• As an alternative to the lever mechanism shown in FIG. 18A, a cam can be used to rotate the jaw, as depicted in FIGS.[0098]18B-D. In particular,jaw411 rotates aroundpivot413. Rotation ofrod415 causesball417 to change position relative to the position ofrod415.Ball417 fits intotrack419 in the end ofjaw411. Also,ball417 fits into a notch in an off center position in the end ofrod415 such that rotation ofrod415 movesball417 up or down. Lowering of the ball results in the opening ofjaw411 relative tojaw421.Rod415 is rotated usinglever423, as shown in FIG. 18D. Generally a half rotation ofrod415 results in motion ofjaw411 from a closed position to its open. position.
• As depicted in FIG. 17,[0099]fastener applicator404 applies a fastener, such as a tack. Further details aboutfastener applicator404 can be seen in FIG. 19.Fastener applicator404 holdstack424 andcap426 in separate housings for deployment. Whenjaws428,430 are opened by the movement oflever432 in the direction shown by thearrow431 in FIG. 19A,rod434 slidestack424 withintrack436 to aposition aligning cap426 withtack424, as shown in FIGS. 19B and 19C.Jaws428,430 rotate relative to each other by way oflever arm438 or other mechanical link, such as a cam. Whenjaws428,430 subsequently are closed,tack424 engagescap426, as shown in FIG. 19D, thereby fasteningleaflets122,124.Jaws428,430 can be opened to releasetack424 and fastenedleaflets122,124.
• While the above grippers and fastener applicators can be used for an atrial or ventricular approach, other designs for the gripper are particularly adapted for gripping leaflets from an atrial approach. Referring to FIG. 20,[0100]gripper438 includesgraspers440 used to grasp eachleaflet122,124. To push the leaflets towardgraspers440, plunger446 includes two ormore arms450,452. In an alternative embodiment depicted in FIG. 21, aballoon plunger454 is used.Balloon plunger454 is deflated for delivery and removal of the instrument throughcardiac catheter126 and inflated within the heart for use to guide the leaflets to thegraspers440.
• With either embodiment of the plunger,[0101]shaft456 can be pulled to draw spring loadedgraspers440 towardplunger446 or454 to gripleaflets122,124 withingrasper440. Alternatively,plunger446 or454 can pushleaflets122,124 towardgraspers440. In any case, asplunger446 or454 reaches a certain position relative tograspers440 so thatgraspers440 are within reach ofleaflets122,124,shaft456 is pulled back to retractgraspers440, which claspleaflets122,124 betweengraspers440 andgrasper tube441. Onceleaflets122,124 are clasped,plunger446,454 can be removed. Afterleaflets122,124 are fastened,graspers440 can be released by extendingshaft456 such thatgripper438 can be withdrawn.Graspers440 should be less than about 10 mm in length.Graspers440 can be curved.
• Another approach to grasping the leaflets from the atrial side is depicted in FIG. 22.[0102]Hooks470,472 are deployed throughcardiac catheter126 to grableaflets122,124.Hooks470,472 preferably havesharp tips480,482 without barbs. Withleaflets122,124 held in place, a variety of fasteners, as described throughout, can be used to fastenleaflets122,124. Onceleaflets122,124 are fastened securely, hooks470,472 can be released and removed by pushinghooks470,472 to release therespective leaflets122,124 androtating hooks470,472 such that they do not grableaflets122,124 when withdrawn.
• Once one embodiment of grasper is holding the leaflets, another type of grasper generally can be substituted for that grasper to hold the leaflets. A wider variety of graspers are suitable for grasping already held leaflets. In this way, a fastener applicator can be used with a more appropriate grasper, if desired. Furthermore, multiple grippers can be used to grasp the leaflets to be fastened. For instance, a hook as shown in FIG. 22 can be used to grab one leaflet while jaws such as shown in FIGS.[0103]18A-D can be used to grab the other leaflet. As another example, two sets of jaws can be used, each grabbing one leaflet.
• With respect to fastener applicators, a spring fastener embodiment is depicted in FIGS.[0104]23-24.Leaflets122,124 are drawn intocavities500,502 with suction similar to that applied by the device in FIG. 15. Vacuum is applied by way oflumen504.Spring506 is pushed and rotated usingrotating shaft508.End510 ofspring506 catches a leaflet such that rotating thespring506 causesspring506 to spiral throughleaflets122,124 as shown in FIG. 24,fastening leaflets122,124 together. Afterspring506 is placed through the leaflets, vacuum is released andlumen504 is withdrawn.
• Referring to FIGS.[0105]25-32, another embodiment of a fastener applicator uses afastener clip button540 which includes afirst portion542 and asecond portion544. Referring to FIGS. 27 and 28,first portion542 includesspikes546 extending from afirst surface548 ofbase550.Base550 hasnotches552 at the edge ofsecond surface554 at a position rotated 90 degrees relative to spikes546. The center ofbase550 has anopening556 withwings558 oriented towardnotches552.Second surface554 includesindentations560adjacent opening556 oriented towardspikes546.
• Referring to FIGS.[0106]29-31,second portion544 includesperforations566 which have a diameter equal to or slightly smaller than spikes546.Tabs568 extend fromfirst surface570 ofbase572.Tabs568 includelips574 that can engagenotches552.Base572 includes anopening578 withwings580.Base572 is slightly noncircular to allow fortabs568.
• FIG. 32 displays[0107]first portion542 engaged withsecond portion544. Whenportions542,544 are engaged,spikes546 engageperforations566 andtabs568 engagenotches552. The leaflets are positioned in the separation betweenbase550 andbase572.
• Referring to FIG. 25, to deploy[0108]clip button540,first portion542 is positioned withfirst applicator580.First applicator580 includes acentral core582 with aknob584 at the end of thecentral core582, as shown in FIG. 25A.Knob584 engagesindentations560 when first portion is positioned onfirst applicator580, and can pass throughwings558 when oriented accordingly for removal offirst applicator580.First applicator580 also includestubular portion588, which slides overcentral core582. Whenknob584 engagesindentations560 andtubular portion588 engagesfirst surface548,first portion542 is held firmly byfirst applicator580. Preferably,first portion542 is placed in position near the leaflets prior to grasping of the leaflets by a gripper. Once grasped, the leaflets can be pierced withspikes546 offirst portion542.
• After[0109]spikes546 are inserted through the leaflets,tubular portion588 can be removed throughcardiac catheter126. Then,second applicator590 can be slid overcentral core582, as shown in FIG. 26.Second applicator590 is used to engagesecond portion544 withfirst portion542.Second applicator590 can pushsecond portion544 into place, or, alternatively,second applicator590 can holdsecond portion544 using a fastener such as threads or a clamp, asfirst portion542 is pulled against it. Aftersecond portion544 engagesfirst portion542,second applicator590 is removed throughcardiac catheter126.Central core582 is removed by firstrotating knob584 such thatknob584 passes throughwings558 and580.Clip button540 remains fastened to the mitral valves leaflets.
• Another embodiment of a fastener uses a deformable ring. Different variations of the ring are available. A first embodiment of a spring loaded ring is depicted in FIGS. 33 and 34. Spring loaded[0110]ring600 has afirst spike632 at the end ofcrescent portion604.Second spike606 is initially located incavity608 withincrescent portion604.Spring610 is located betweensecond spike606 andsurface612. Abutton lock614 holdssecond spike606 withincrescent portion604 until deployment of spring loadedring600. When thelock614 is released,first spike602 andsecond spike606 pierce the leaflets and secure them together. Alternative embodiments of the spring loaded ring can employ dual springs with a spike being propelled by each spring. If desired, the spikes can be retractable such that the ring is used to hold the leaflets while another fastening approach is used to secure the leaflets.
• Referring to FIGS. 35 and 36,[0111]crimp ring630 includespoints632,634 and handles636,638. Betweenhandles636,638 is anotch641.Notch640 provides a weak location for bendingpoints632,634 toward each other, as shown in FIG. 36.Crimp ring630 is placed near the grasped leaflet. Then, handles636,638 are rotated away from each other to place thecrimp ring630 in the closed crimped position shown in FIG. 36 withpoints632,634 piercing respective leaflets.
• Rings such as spring loaded[0112]ring600 andcrimp ring630 can be applied with anapplicator640, as depicted in FIGS. 37 and 38.Ring642 is brought up toleaflets122,124 and deformed to pierceleaflets122,124.Applicator641 can include leverarms650 and/or other implements to assist with deployment ofrings600 or630. For example, for spring loadedring600, eitherlever arms650 or another implement releases lock614. Forcrimp ring630, leverarms650 hold handles636,638 and rotate handles to crimp the ring to bringpoints632,634 toward each other.
• An automatic suture device can be used as a fastener. One embodiment of an automatic suture device is described in U.S. Pat. No. 5,417,700, to Egan, incorporated herein by reference. Referring to FIGS.[0113]39-42,suture device658 includeshollow needles660,662, which can rotate to pierceleaflets122,124. Suture664 (FIG. 42) is threaded through channel666 (FIG. 41) withinhollow needles660,662. Suture664 can be secured with an ultrasonic weld formed betweenweld anvil668 andwelding horn670. Suture664 can be pulled tight prior to welding.
• An alternative embodiment of an automatic suture device is shown in FIGS. 43 and 44. The[0114]suture device700 includes a curved needle702. Needle702 has apoint704 and ablunt end706. Needle702 lies within slot708.Suture710 is threaded throughchannel712. Suture710 exitschannel712, crosses to the opposite opening into slot708, circumscribes slot708 and attaches to needle702 atblunt end706.
• [0115]Suture710 is pulled, which rotates needle702, impalingleaflets122,124 withpoint704. Needle702 is rotated about360 degrees such that needle702 has passed throughleaflets122,124. Following complete rotation of needle702,suture710 is threaded throughleaflets122,124. Withdrawal ofsuture device700 through the catheter introducer pullssuture710 throughleaflets122,124. Suture710 can be tied, as described above with respect to FIG. 3, to secureleaflets122,124. Alternatively, asuture clip132 can be used to securesuture710, as shown in FIG. 5.
• All of the devices described above can be constructed from standard biocompatible materials including a variety of metals, such as stainless steel and titanium, and polymers, such as polysulfone. The materials can be selected as appropriate for a particular application. Furthermore, the fasteners can be coated with a surface modifier such as polytetrafluoroethylene (PTFE), i.e., Teflon®, or an antimicrobial coating, such as silver metal or a silver compound. Antimicrobial metal coatings are further described in copending and commonly assigned U.S. patent application Ser. No. 08/974,992 to Ogle et al., entitled “Medical Article with Adhered Antimicrobial Metal,” incorporated herein by reference.[0116]
• Surgical Procedure[0117]
• In preferred embodiments of the procedure, the repairs are performed on a beating heart. Alternatively, the heart can be stopped during the procedure. Cardioplegia, i.e., stopped cardiac contraction, can be induced by certain chemicals such as cold potassium-containing solutions that are introduced into the myocardium. The chemical induction of cardioplegia requires the isolation of the heart and ascending aorta from the rest of the patient's vascular system. Procedures using cardioplegia are less desirable since they require cardiopulmonary bypass, which increases patient risk factors.[0118]
• For cardiac catheter based embodiments, one or more access points are used along the patient's chest, generally positioned between adjacent ribs. The access points provide access to the heart. Incisions are made to initiate the access points. Trocar sheaths, such as those used for the performance of laparoscopic procedures, can facilitate use of the access points as described in published PCT application WO 94/18881 to Stanford Surgical Technologies, Inc., incorporated herein by reference. Alternatively, soft tissue retractors, such as those used in pediatric open chest procedures can be utilized to facilitate use of the access points. Suitable location of the access point(s) can be determined based on the approach appropriate for the gripper/fastener applicator to be used.[0119]
• Once the heart is accessed, a guide wire can be inserted through the wall of the heart either near the apex of the heart into the left ventricle or near the top of the heart into the left atrium. A dilator can be slid over the guide wire to expand the opening into the heart. Suitable guidewires and dilators are available from Daig Corp., Minnetonka, Minn. A cardiac catheter with a hemostasis valve, described above, is deployed over the dilator. The cardiac catheter provides access. into the heart to deliver the repair device or devices.[0120]
• Alternatively, a cardiac catheter can be inserted through an incision in the wall of the heart at the desired location. As during normal cannulation, a purse string suture can be applied at the point where the cardiac catheter enters the heart to reduce any bleeding. The suture can be applied, for example, using a piece of suture with a needle on both ends. The needles can be manipulated using forceps or the like. After the desired stitching is performed, the needles can be cut off using endoscopic scissors. Additional cardiac catheters can be placed near or into the heart, as desired.[0121]
• Once the cardiac catheter is in place, the gripper/fastener instruments can be directed at the mitral or tricuspid valve to perform the repair. All of the instruments are designed such that the appropriate manipulations by the appropriate health care professional are performed at the proximal end of the cardiac catheter.[0122]
• Following completion of the bow-tie repair, the cardiac catheter is removed. The procedures used to deploy the cardiac catheter preferably minimize the damage to the heart muscle by separating the tissue without significantly tearing the tissue. Nevertheless, stitches or staples can be used to close the incision at the point where the cardiac catheter was inserted. Once access to the heart has been closed, the incision providing access into the chest cavity is closed.[0123]
• Alternatively, a less invasive, percutaneous vascular approach can be used. There are two, alternative, percutaneous vascular approaches to positioning the catheter for the medical procedure. One is to introduce the catheter into the femoral artery by a standard introducer sheath and advance it up the aorta, across the aortic valve into the left ventricle and then position its tip under the mitral annulus. This is commonly referred to as the “retrograde” approach.[0124]
• The other approach, commonly referred to as the transseptal approach, is to introduce a transseptal sheath apparatus, a long single plane curve introducer, into the right femoral vein and advance it through the inferior vena cava into the right atrium. A puncture is then made through the fossa ovalis in the intraatrial septum, and the apparatus is advanced into the left atrium where the trocar and dilator of the apparatus is removed, leaving the sheath in position in the left atrium. Once the valve is accessed, the repair can be completed as described above.[0125]
• Edge-to-edge mitral valve repair provides a simple and effective repair technique relative to complex and surgically demanding approaches of chordal shortening, resectioning, chordal transposition or artificial chordae replacement. The edge-to-edge repair is particularly effective with severe isolated mitral regurgitation or in association with coronary artery bypass surgery. The present approach provides the benefits of the edge-to-edge repair without the trauma of open heart surgery and cardiopulmonary bypass. Thus, the procedure can be accomplished concomitant with coronary artery bypass graft (CABG) or as a stand alone outpatient procedure in a cardiac catheterization laboratory. The advantages include reduced cost, hospitalization and patient recovery times. With minimal trauma to the patient, it may be desirable to perform the repair earlier before the disease has progressed to a serious level. Thus, more repair procedures may be performed, preventing further progression of the disease, obviating the need for more serious invasive procedures.[0126]
• The instruments described above may be distributed in the form of a kit. Generally, the kit includes a fastener applicator and a suitable cardiac catheter or other catheter for a vascular approach. The kit may also include a suitable gripper for use with the fastener applicator. Alternatively, the kit may include only a fastener (fastener applicator) and/or a gripper. The kit preferably includes instructions for the performance of mitral and/or tricuspid valve repair. In particular, the instructions can describe the particular use of the fastener applicator and/or the grippers.[0127]
• Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.[0128]

Claims (35)

What is claimed is:

1. A kit comprising a cardiac catheter and a leaflet fastener applicator, said cardiac catheter having suitable dimensions for deployment and insertion into a human heart in the vicinity of the mitral or tricuspid valve, said leaflet fastener applicator having a size allowing insertion through said cardiac catheter and being capable of holding portions of opposing heart valve leaflets.

2. The kit ofclaim 1 wherein said fastener applicator comprises opposing jaws, one of said jaws having a site for holding a tack and the second of said jaws having a site for holding a cap.

3. The kit ofclaim 1 wherein said fastener applicator comprises a stapler.

4. The kit ofclaim 1 wherein said fastener applicator comprises a needle and suture, which passes through a leaflet.

5. The kit ofclaim 1 wherein said fastener applicator comprises sets of opposing arms where each set has suitable dimensions for holding a heart valve leaflet.

6. The kit ofclaim 1 wherein said fastener applicator comprises a ring.

7. The kit ofclaim 1 wherein said fastener applicator comprises a clip button including a first element with spikes and a second element that clips onto said first element.

8. The kit ofclaim 1 further comprising a gripper, said gripper including a tube having a proximal end and a distal end, opposing gripper arms at said distal end of said tube, and an actuator at said proximal end of said tube such that motion of said actuator changes the relative position of said gripper arms.

9. The kit ofclaim 1 further comprising a gripper, said gripper having a suitable opening for the application of suction to a heart valve.

10. The kit ofclaim 1 further comprising instructions describing use of said cardiac catheter and said leaflet fastener applicator.

11. A method of repairing a valve of a beating heart, said method comprising:

a) inserting the distal end of a catheter into the heart to provide access to said valve; and

b) fastening together portions of leaflets of said valve using a leaflet fastener applicator inserted through said catheter.

12. The method ofclaim 11 wherein the catheter is inserted through an opening in the wall of said beating heart.

13. The method ofclaim 11 wherein the catheter is introduced into the heart by way of a blood vessel.

14. The method ofclaim 11 wherein said fastening of said opposing leaflets comprises placement of a sharp projection through said leaflets.

15. The method ofclaim 11 wherein said fastening of said leaflets comprises suturing together said opposing leaflets.

16. The method ofclaim 11 further comprising gripping said leaflets with a gripper prior to fastening said leaflets.

17. The method ofclaim 16 wherein said gripper comprise a tube having a proximal end and a distal end, opposing gripper arms at said distal end of said tube, and an actuator at said proximal end of said tube such that motion of said actuator change the relative position of said gripper arms.

18. The method ofclaim 16 wherein said gripper has a suitable opening for the application of suction to a heart valve.

19. The method ofclaim 11 further comprising inserting a wire through said wall of said heart to initiate an opening through which said cardiac catheter is inserted.

20. The method ofclaim 11 further comprising making an incision in the wall of the heart for said insertion of said catheter.

21. A device comprising a catheter and a leaflet fastener applicator, said catheter having a proximal end, a distal end and suitable dimensions for insertion into a heart, said leaflet fastener applicator passing through said catheter such that an actuating element projects from said proximal end of said catheter while a fastening element projects from said distal end of said catheter.

22. The device ofclaim 21 wherein said actuating element comprises a length of suture extending to said distal end of said leaflet fastener applicator.

23. The device ofclaim 21 wherein said actuating element comprises a lever that controls the delivery of a fastener.

24. The device ofclaim 21 further comprising a gripper inserted through said cardiac catheter such that gripping appendages project from said distal end and an actuating element projects from said proximal end, where said actuating element controls said gripping appendages.

25. A heart valve leaflet fastener comprising two pairs of arms, each pair having a suitable size for fastening heart valve leaflets and said two pairs of arms capable of fastening two adjacent leaflets.

26. The heart valve leaflet fastener ofclaim 26 wherein said arms flex relative to a central core, and wherein said fastener has a locked position where each said pair of arms meet under tension.

27. The heart valve leaflet fastener ofclaim 26 wherein one of said arms of each pair includes a projection for piercing a leaflet.

28. A heart valve gripper/fastener applicator comprising a gripper and a fastener applicator wherein said gripper and said fastener applicator extend from a single shaft.

29. The gripper/fastener ofclaim 28 wherein said gripper comprises two opposing jaws.

30. The gripper/fastener ofclaim 28 wherein said fastener comprises two opposing jaws, one of said jaws having a site for holding a tack and the second of said jaws having a site for holding a cap.

31. A heart valve leaflet fastener applicator comprising two opposing jaws, one of said jaws having a site for holding a tack and the second of said jaws having a site for holding a cap.

32. The heart valve leaflet fastener applicator ofclaim 31 wherein said jaw having a site for holding a tack further comprises a slot wherein a tack can be shifted to a position opposite said site for holding a cap.

33. A gripper comprising a plunger that slides over an inner shaft and arms having suitable dimensions for gripping heart valve leaflets, said plunger slides such that interaction of heart valve leaflets with said plunger directs said leaflets toward said arms.

34. The gripper ofclaim 33 wherein said plunger is a balloon plunger that can be inflated and deflated.

35. A fastener applicator comprising a first shaft, a first portion of a button clip having a sharp projection for piercing a heart valve leaflet, a second shaft that slides over said first shaft, and a second portion of said button clip having an opening to engage the projection of said first portion of said button clip, said second portion of said button clip sliding over said first shaft and not over said second shaft such that second shaft can direct said second portion toward said first portion.

Images