RELATED APPLICATIONSThe present application is a division of co-pending U.S. utility patent application Ser. No. 12/031,490, filed Feb. 14, 2008 and entitled “Suture and Method for Repairing a Heart,” which claims priority from U.S. provisional patent application Ser. No. 60/889,921, filed on Feb. 14, 2007 and entitled “Suture and Method for Repairing a Heart,” the entire contents of each of which are expressly incorporated herein in their entirety.
FIELD OF THE INVENTIONThe present invention relates generally to medical devices, and more particularly, to implantable medical devices for treating diseases, disorders, and malformations of a heart
BACKGROUND OF THE INVENTIONThe function of the heart may be seriously impaired if any of the heart valves is not functioning properly. The heart valves may lose their ability to close properly due to disease or defects, such as (for example) by a mitral or tricuspid valve leaflet becoming partially or completely detached from a papillary muscle (e.g., by ruptured chordae tendinae) thereby resulting in prolapsing of the leaflet. The inability of the heart valve to close will cause a leak backwards, commonly referred to as regurgitation, through the valve. On the left side of the heart, regurgitation through the mitral valve may seriously impair the function of theheart1 since a portion of the heart stroke volume of blood will return from the left ventricle to the left atrium instead of passing through the aortic valve to the organs of the body. Accordingly, the damaged heart is required to work much harder to maintain adequate circulation, a condition that inevitably ends in heart enlargement and/or heart failure.
Repairing heart structures by means of surgery often involves the use of needle and thread for attaching tissue portions together or for attaching a prosthetic implant to tissue. A traditional surgical suture typically has a needle attached to one or both ends of a thread. In a common method for attaching a suture directly to tissue (i.e., when not directly attaching tissue to tissue or tissue to implants), one needle is passed through the tissue one or several times and advanced to about the middle of the thread. The thread may or may not be knotted at this point to prevent the thread from moving slidingly through the tissue. Whether knotted or not, the end result is that the thread is attached to the tissue.
While performing heart surgery, the above technique is often used in chordae tendinae replacement. A first end of a suture thread is attached to a papillary muscle inside the left ventricle of a heart. The appropriate length of the thread is determined, and the other end of the suture thread is stitched through one or more of the leaflets of the mitral valve for creating artificial chordae tendinae. This procedure can be performed for treating a regurgitant mitral valve when the reason for the regurgitation (i.e., leak) is prolapse of a mitral valve leaflet into the left atrium. However, attaching a thread (i.e., suture) to the papillary muscle can be cumbersome due to difficulties in accessing the surgical site, including limitations in physical and visual access. The limited visual access results from the relatively narrow space between the leaflets of a mitral valve. Furthermore, access to the desired portion of the heart can be difficult while performing conventional open-heart surgery (i.e., with a sternal split). Further difficulties can arise as a result of the difficult angles at which the instruments are held.
Due to the shortcomings associated with existing medical procedures, the attachment of artificial chordae can be time consuming and may often be inaccurate. Accordingly, a need exists for improved devices and methods for creating artificial chordae. To reduce the trauma to the patient, it is desirable that the devices and methods be adapted for use in a percutaneous or minimally-invasive procedure. The present invention addresses this need.
SUMMARY OF THE INVENTIONEmbodiments of the present invention provide devices and methods for securely attaching a thread to tissue without the need for conventional suturing, thereby eliminating the need for surgical instruments such as needle holders and forceps. Some embodiments are adapted for attaching thread to heart wall tissue; however, the features of the invention are also applicable to a wide variety of other medical procedures wherein it is desirable to securely anchor a suture thread or other structure to a portion of tissue without using a needle and forceps.
Embodiments of the invention include new devices and methods for creating artificial chordae and for repairing various other heart defects without suturing. In one variation, embodiments may be used to reduce dilation of a heart wall, such as in the left ventricle. In some embodiments of methods of use, these treatments are performed in a percutaneous manner by means of catheter access.
In one aspect, a suture device for repairing a human heart comprises a thread, an anchor, and a delivery system. The anchor is configured to engage tissue, such as tissue of an inner wall of the heart. The thread is attached to the anchor at one end and configured to be attached (via conventional suture tying, clipping, or otherwise) to heart tissue (such as valve leaflet tissue) at another end. The delivery system is configured to deliver the anchor in a delivery configuration, and to deploy the anchor into tissue at a desired location (such as at or adjacent papillary muscles of the heart). In some embodiments, the anchor comprises memory materials (such as Nitinol) and/or is biased toward the deployed state so that the anchor is configured to expand from a delivered state to a deployed state when ejected from a distal end of a sheath on the delivery catheter.
In one arrangement, the anchor is configured for attachment at or adjacent papillary muscle tissue, and the thread is configured to be coupled to the anchor and attached to a leaflet for creating an artificial chordae tendinae. The delivery system includes a sheath or other structure for delivering the anchor in a collapsed condition to the desired deployment location.
In another embodiment, a method for repairing a human heart comprises gaining access to the inner portion of a human heart and deploying a suture anchor. A thread is then attached to tissue and coupled to the anchor. The thread may be foreshortened to a desired length and then locked in the foreshortened position. This method may be used for replacing chordae tendinae, for treating dilation of a left ventricle, or for other heart treatments.
In another embodiment, a method of treating mitral valve regurgitation comprises performing open heart surgery for gaining direct access to the left atrium and the mitral valve. An anchor is deployed along or adjacent to the papillary muscle, and an elongate member (e.g., thread) is attached at a first end to the anchor and at a second end to a mitral valve leaflet. If desired, the length of the elongate member may be adjusted to close a gap in the mitral valve, and the thread is then knotted or otherwise locked to the mitral valve leaflet to maintain the desired length.
In another embodiment, a method of treating an enlargement of a left ventricle of a heart comprises accessing the inside of a heart (e.g., through surgical incision) and deploying multiple anchor members at locations along the left ventricular muscular wall. Threads extending from the anchor members are connected to a lock. The threads are shortened to pull the anchors, and therefore the muscular wall, into closer proximity to the lock and to the other anchors. The threads are then locked in the shortened condition to maintain the anchors in closer proximity, thereby reducing the size of the left ventricle. In one embodiment, the lock is located within the left ventricle. In another embodiment, the lock is located within a different chamber of the heart, such as the right atrium or the right ventricle. In another embodiment, the lock is located outside of the heart, such as, for example, at or adjacent the apex of the heart.
In another aspect, a method of treating an enlargement of a ventricle of a heart comprises accessing the inside of a heart via a percutaneous or surgical incision, deploying anchors in the left ventricular muscular wall wherein suture threads extend from the anchors, and connecting the suture threads to a lock. The anchors are allowed to grow into the tissue such that they are securely attached to the heart wall. After sufficient time, the inside of the heart may be re-accessed by means of catheter-based technology for localizing the lock, and the suture threads are then foreshortened and locked.
BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 shows a cross-sectional view of a human heart with a device according to an embodiment of the invention deployed therein;
FIG. 2A illustrates a device comprising an anchor, an elongate member, and hooks according to an embodiment of the invention;
FIG. 2B illustrates a device comprising an anchor and an elongate member according to a further embodiment of the invention;
FIG. 2C illustrates a device comprising an anchor and an elongate member according to a further embodiment of the invention;
FIG. 3A depicts a device comprising an anchor and rod-like elongate member according to a further embodiment of the invention;
FIG. 3B depicts a device similar to that ofFIG. 3A with a magnetic connector secured thereto according to an embodiment of the invention;
FIGS. 4A and 4B illustrate an expandable anchor, in unexpanded and expanded configurations, respectively, according to an embodiment of the invention;
FIGS. 5A through 5D illustrate a method of delivering the device wherein a delivery system comprises a sheath for maintaining the anchor in the collapsed position during advancement according to an embodiment of the invention;
FIG. 6 illustrates an embodiment of the invention during implantation wherein a suture thread is stitched through the anterior mitral valve leaflet to create replacement chordae tendinae;
FIG. 7 illustrates a device wherein suture is stitched through the mitral valve annulus for pulling the papillary muscle closer to the annulus, thereby relieving strain on the chordae tendinae according to an embodiment of the invention;
FIG. 8A illustrates anchors are configured for engaging the inner wall of the left ventricle and aneurysms according to an embodiment of the invention;
FIG. 8B illustrates the device ofFIG. 8A after foreshortening and locking the threads for reshaping the left ventricle according to an embodiment of the invention;
FIG. 8C illustrates an embodiment of the invention wherein the threads are captured and held in a locking mechanism located outside the left ventricle;
FIG. 8D illustrates an embodiment of the invention wherein the threads are captured and held in a locking mechanism located in the right ventricle along the interventricular septum;
FIG. 9 illustrates a further embodiment of the invention wherein the anchor of the suture is deployed inside a papillary muscle and the elongate member (e.g., thread) is locked inside the right atrium close to the annulus of the mitral valve, thereby closing the papillary muscle to the annulus and relieving tension on the chordae tendinae;
FIG. 10A illustrates a further embodiment of the invention wherein the anchor is located just below the mitral valve in the left ventricle wall and the locking mechanism is located in the right ventricle on the septum, thereby pulling the posterior leaflet from lateral towards the septum and shortening the antero-posterior diameter (also called septo-lateral distance) for repairing a mitral valve leak;
FIG. 10B depicts an embodiment of the invention wherein the anchor is located close to the mitral valve in the ventricular septum and the thread is running through the coronary sinus and the elongate member (e.g., thread) is locked inside the coronary sinus, in the orifice of or just outside the coronary sinus orifice, thereby pulling the posterior leaflet from lateral towards the septum and shortening the anterior-posterior diameter for repairing a mitral valve leak;
FIG. 11 depicts an anchor deployed in a heart according to an embodiment of the invention;
FIGS. 12A-12D depict a method for deploying a device according to an embodiment of the invention;
FIG. 13A is a perspective view of a suture deployment device according to an embodiment of the invention;
FIGS. 13B and 13C are top and side views, respectively, in partial cross section of the distal portion of the suture deployment device ofFIG. 13A;
FIG. 14A is a front view of a heart, in cross section, with a suture deployment device advanced to a valve leaflet to deploy a suture according to an embodiment of the invention;
FIGS. 14B-14D are side views, in cross section, of the distal end of the suture deployment device ofFIG. 14A deploying a suture through valve leaflet tissue;
FIG. 14E is a front view of the heart, in cross section, fromFIG. 14A with the suture deployment device having a suture secured to the valve leaflet;
FIG. 15 is a front view of a heart, in cross section, with a suture, anchor, and elongate member deployed therein according to an embodiment of the invention;
FIG. 16A is a side view of a suture securing and cutting catheter for use in securing suture according to an embodiment of the invention;
FIGS. 16B-16D are exploded and assembled views of the distal portion of the suture securing and cutting catheter ofFIG. 16A;
FIGS. 17A and 17 B are front views of a heart, in cross section, with a suture securing and cutting catheter advancing a suture clip along suture lines and an elongate member to form a replacement chordae tendinae according to an embodiment of the invention;
FIG. 17C is a front view of the heart ofFIGS. 17A-17B with the suture clip deployed and excess suture removed to form a replacement chordae tendinae according to an embodiment of the invention; and
FIGS. 18A-18B are front views of a heart, in cross section, with a suture delivery catheter deploying suture through papillary muscle tissue according to an embodiment of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTSWith reference toFIG. 1, adevice10 according to the invention is depicted deployed within aheart12. Theheart12 has four chambers, known as theright atrium14,right ventricle16, leftatrium18, and leftventricle20. In the particular embodiment depicted, thedevice10 is deployed in theleft ventricle20. Theheart12 has a muscularouter wall22, with an interatrial septum24 (not visible inFIG. 1) dividing theright atrium14 and leftatrium18, and a muscularinterventricular septum26 dividing theright ventricle16 andleft ventricle20. At the base of theheart12 is the apex28.
Blood flows through thesuperior vena cava30 and theinferior vena cava32 into theright atrium14 of theheart12. Thetricuspid valve34, which has threeleaflets36, controls blood flow between theright atrium14 and theright ventricle16. Thetricuspid valve34 is closed when blood is pumped out from theright ventricle16 to the lungs. Thereafter, thetricuspid valve34 is opened to refill theright ventricle16 with blood from theright atrium14. Lower portions andfree edges42 ofleaflets36 of thetricuspid valve34 are connected viatricuspid chordae tendinae44 topapillary muscles46 in theright ventricle16 for controlling the movements of thetricuspid valve34. Blood from theright ventricle18 is pumped through thepulmonary valve38 to thepulmonary artery40 which branches into arteries leading to the lungs.
After exiting the lungs, the newly-oxygenated blood flows through thepulmonary veins48 and enters theleft atrium18 of theheart12. Themitral valve50 controls blood flow between theleft atrium18 and theleft ventricle20. Themitral valve50 is closed during ventricular systole when blood is ejected from theleft ventricle20 into theaorta52. Thereafter, themitral valve50 is opened to refill theleft ventricle20 with blood from theleft atrium18. The mitral valve has two leaflets (anterior leaflet54aandposterior leaflet54p), lower portions andfree edges56 of which are connected viamitral chordae tendinae58 topapillary muscles60 in theleft ventricle20 for controlling the movements of themitral valve50. Blood from theleft ventricle20 is pumped by power from the musculature of theheart wall22 and the muscularinterventricular septum26 through theaortic valve62 into theaorta52 which branches into arteries leading to all parts of the body.
With reference now toFIGS. 2A-2C, for purposes of illustration, various embodiments of atreatment device10 are shown. In the depicted embodiments, thetreatment device10 generally comprises ananchor70 and anelongate member72. Theanchor70 provides a mechanism for attaching the device to an inner heart wall or other deployment site without requiring the use of a suturing needle. Theelongate member72 is coupled to theanchor70, such as by being looped therethrough or by other attachment thereto. In various applications, as will be described in more detail below, theelongate member72 may be used for replacing a damaged or ruptured chordae tendinae or may be used for pulling a heart wall inward to reduce dilation of a heart wall. Features of anchors and elongate members according to various embodiments of the invention will be described in more detail below.
In the particular embodiment ofFIG. 2A, theelongate member72 comprises athread74 terminating at eitherend76 in hooks or needles78. Thethread74 passes through a hoop-like structure80 on theanchor70. The hooks or needles78 on the free ends76 of thethread74 provide a physician or other user with the ability to penetrate tissue in the heart or elsewhere for fixing the free ends76 of theelongate member72.
Note that thethread74 or other elongate member could terminate at free ends76 without hooks, as depicted inFIG. 2B, which could be useful where one or more of the free ends76 are to be passed through tissue using adetachable needle82 or similar suturing device. Also, anelongate member72, such as one ormore threads74, could be secured permanently or through other methods to theanchor70, such as being secured directly and fixedly to theattachment point84 depicted inFIG. 2C.
A thread portion of adevice10, such as thethread74 depicted inFIGS. 2A-2C, may be formed of various materials, including PTFE (polytetrafluoroethylene, aka Goretex®), polypropylene (e.g. Prolene), or other suture materials such as Ti-crone or Ethibond. The hooks or needles could be attached to the threads according to known techniques, including techniques applied by suture material producers.
FIG. 3A depicts a further embodiment of the invention, wherein theelongate member72 comprises a rod-like structure86. In the particular embodiment depicted, the rod-like structure86 is generally cylindrical, although other configurations are also possible. The rod-like structure86 may be solid or hollow, depending on the particular configuration and application. The rod-like structure86 may be generally rigid or may be generally flexible, or may be configured to be partially rigid but still have some flexibility so that it acts as a shock-absorbing structure when under compression.
FIG. 3B depicts a further embodiment of the invention, wherein theelongate member72 comprises a rod-like structure86 having amagnet88 secured at thefree end76. Themagnet88 might be used to pick up the elongate member72 (in the form of arod76 or thread, etc.) at a later point of time, e.g., after the anchor has been deployed and grown solid into the tissue and the user desires to pull hard on theelongate member72. Themagnet88 might be used to change an attached part of a device after a long time has passed, such as where the attached part is degenerated and has to be changed (e.g. a lock or a valve). Themagnet88 may also be used as a guiding aid, for instance when homing in and locking an elongate member (such as a thread) in a lock under open or percutaneous operations when the heart is beating and full of blood.
With reference now toFIGS. 4A and 4B, for purposes of illustration a particular embodiment of ananchor portion100 is described in more detail. Theanchor portion100 comprises atubular body102 having adistal end104 and aproximal end106, with a plurality ofelongated prongs108 located on thedistal end104 and acoupling member110 located on theproximal end106. In the illustrated embodiment, thecoupling member110 takes the form of a loop.
Theelongated prongs108 may be configured to self-expand from the compressed configuration ofFIG. 4A to a “flowered” or expanded configuration ofFIG. 4B. This expansion may be achieved with a self-curvingarea112 that deflects theelongated prongs108 radially outward from the center of the generallytubular body102. Theprongs108 may be pointed and/or barbed to facilitate penetration of and engagement with the muscular wall of the heart.
Theanchor portion100 may be formed from various materials and/or combinations thereof. In one embodiment, theanchor portion100 is formed from a single tube of shape memory material, such as, for example, Nitinol. During manufacture, the shape memory material (or other material forming the anchor portion100) may be cut using a mechanical or laser cutting tool. After cutting the tube, the expanded or flowered shape can be imparted to the memory of the shape memory material with techniques known in the art (e.g. heat setting the shape). Note, however, that theanchor100 is not limited to construction from Nitinol or other shape memory materials, and could be formed from any number of materials, including metals, plastics, composite structures, etc.
All or part of the surface of theanchor portion100, including theprongs108, may be configured to promote tissue growth onto and even into its surface. In one example this growth is achieved by providing a relatively rough and/or porous surface along theanchor portion100. Another example is to have one ormultiple holes114 drilled through theanchor portion100 and itsprongs108, allowing scar tissue fibrocytes to grow through theseholes114 and thereby add strength to the fixation. Additionally, biological coatings of the types known in the art can be included on the surface of theanchor portion100 to promote healing and tissue growth.
With reference toFIGS. 5A-5D, a method of deploying ananchor100 will be described in more detail. As shown inFIG. 5A, ananchor portion100 is secured within adistal end portion120 of ananchor delivery catheter122. Thedistal end portion120 includes adistal end sheath124 that surrounds theanchor portion100 and maintains theanchor portion100 in a compressed configuration during delivery to a treatment site. Theanchor delivery catheter122 may also includes an expandable structure such as anexpandable balloon126, which in the embodiment depicted is positioned around a portion of thedistal end sheath124.
Using the illustrated delivery system, the anchor delivery catheterdistal end portion120 containing theanchor portion100 is advanced through a chest wall and through the cardiac tissue (or through other delivery routes) into a desired heart chamber. When theanchor portion100 and surroundingdistal end sheath124 are advanced just in front of the orifice of the valve to be treated (such as a mitral valve or a tricuspid valve), theexpandable balloon126 can be expanded, as depicted inFIG. 5B. Theexpandable balloon126 when expanded may be just a little smaller than the valve orifice, but larger than the distance between chordae tendinae and allow advancement of the anchor delivery catheterdistal end portion120 past the chordae tendinae and other sub-valvular structures by preventing the anchor delivery catheterdistal end portion120 from becoming entangled within or otherwise passing between such structures in an undesired manner.
When the anchor delivery catheterdistal end portion120 is advanced such that theanchor portion100 is properly positioned at a desired target location within the heart, thedistal end sheath124 opening remains in contact with the target location while theanchor portion100 is pushed distally with respect to thedistal end portion120 by means of pushing on therod86 or72 at the proximal end of thedelivery catheter122, as illustrated inFIGS. 5C and 5D. As theanchor portion100 is exposed to the tissue, theprongs108 expand outwardly. In some embodiments, the expansion of theprongs108 to tissue may advantageously pull theanchor portion100 out of theanchor delivery catheter122 andouter sheath126 and dig into the tissue by its inherent force. A light push forward on thedelivery catheter122 can enable a continuous tissue contact of thedelivery catheter orifice124 to ensure tissue contact with theprongs108
After being released from theouter sheath126, theprongs108 on theanchor portion100 may continue to expand, bending back around towards the generallytubular body102 while grabbing nearby heart tissue. This tissue-engaging action by theprongs108 can help to maintain theanchor portion100 in a stable position within the heart that resists movement due to heart beats, blood flow, and similar actions. In this respect, theanchor portion100 may at least partially “self-deploy” within the heart, requiring little or no extra pressure from theanchor delivery catheter122 to anchor within the muscular wall of the heart. Note that althoughFIGS. 5C and 5D depict theexpandable balloon126 in a deflated condition during deployment (which may be preferable in some applications), the expandable balloon126 (if present) may alternatively be left inflated during deployment of theanchor portion100.
In the embodiments ofFIGS. 5A-5D, theelongate member72 took the form of an elongated rod-like structure86 secured to theanchor portion100 via an anchor portion connection in the form of a screw-like connection130. The elongated rod-like structure86 can be relatively thick and configured to transmit axially rotational movement along its length. When the user desires to remove the elongated rod-like structure86, the user can rotate a proximal portion of the elongated rod-like structure86 (or a proximal portion of a wire secured to the proximal end of the elongated rod-like structure86, wherein the wire may be positioned outside of the patient's body), thereby causing a corresponding rotation of the distal portion of the elongated rod-like structure86 and the screw-like connection130 to theanchor portion100. This rotation will essentially unscrew the screw-like connection130, thereby disconnecting the elongated rod-like structure86 from theanchor portion100.
Theelongate member72, such as the elongated rod-like structure86 depicted, can also serve to retract theanchor portion100 back into thedistal end sheath124 during or after deployment thereof. For example, in the event that the user is not satisfied with the initial deployment of theanchor portion100, the user can pull on the elongated rod-like structure86 while holding still or even advancing thedistal end sheath124. As theanchor portion100 is drawn back into thedistal end sheath124, inward pressure on theprongs108 from thedistal end sheath124 will cause theprongs108 of theanchor portion100 to collapse inwardly, thereby collapsing theanchor portion100 back to its delivery (i.e., predeployment) condition as theanchor portion100 is pulled back into thedistal end sheath124. The user can then redeploy theanchor portion100 in a new position, or can remove theanchor portion100 entirely from the patient.
Note that the anchor portion can be implanted without having the elongate member attached thereto during the implantation procedure. In such embodiments, the elongate member could be secured to the anchor portion after the anchor portion is deployed. In another embodiment, the anchor portion can be deployed with an elongate member secured thereto, but then after the implantation a surgeon or other user could remove the original elongate member and replace it with a substitute elongate member. Also, if a relatively stiffelongated member86 with ascrew attachment130 to the anchoringportion100 is used, a thread elongatedmember72 may be attached to the anchoring portion permanently while the stiffelongated member86 is detached.
FIG. 6 depicts an embodiment of a chordae tendinae replacement procedure using adevice10 according to an embodiment of the invention, wherein ananchor100 is shown after deployment in apapillary muscle60, thereby completing the first stage of the implantation procedure. The twofree ends76 of thesuture threads74 can then be passed (via, e.g., needles78) through a leaflet (which is aposterior leaflet54pin the particular embodiment depicted) of the mitral valve50 (or other tissue, depending on the particular application) by the surgeon or other user. After determination of the length of the hereby created chordae tendinae, thethreads74 are knotted or locked by other fixation means like a suture clip or locking mechanism. Note that the device could be used to replace chordae tendinae of theposterior leaflet54pand/oranterior leaflet54aof themitral valve50, or of any other leaflet of other valves.
With reference toFIG. 7, in ischemic heart disease caused by clogged arteries to the heart muscle, apapillary muscle60 may have moved away from themitral valve annulus51 and thereby be pulling the corresponding leaflet down into the ventricle. The twoleaflets54a,54pcan no longer meet properly, and regurgitation through thevalve50 may occur. In such a case, the anchor can be deployed at or adjacent to the papillary muscle, and one or more of the suture ends76 may be attached to the valve annulus51 (instead of to thevalve leaflets54a,54p), thereby shortening the distance between the displacedpapillary muscle60 and theannulus51 and thereby allowing theleaflets54a,54pto meet again and thevalve50 to again be competent.
FIGS. 8A and 8B depict a method of treating myocardial infarction, a condition which occurs regularly after blockage of the arteries, resulting in heart muscle cell death. As a result thereof, in many cases a weakening of a portion of theheart wall22 or other structure may occur, with a corresponding bulge or other structural deformation to the heart portion. For example, in aheart12 having a weakening of theheart wall22 in the areas adjacent theleft ventricle20, a considerable dilation or bulge can occur in the leftventricular wall area23. With each heart contraction in systole, theleft ventricle20 will bulge outwards instead of properly contracting, causing less blood to leave into the aorta and thereby causing low cardiac output and heart failure. The current invention may be used to treat this condition. As illustrated inFIG. 8A, in one method of usemultiple anchors100 may be deployed in the leftventricular wall area23. Thesuture threads74 can be collected in the center by means of a knot or other locking mechanism (such as a suture clip140) and eachthread74 may be pulled inwards toward the center until the bulging is adequately reduced. Thesuture threads74 or other elongate members are then locked via the knot or other locking mechanism to maintain theleft ventricle20 in the reshaped condition, as depicted inFIG. 8B.
FIG. 8C illustrates an alternative configuration for treating a weakenedheart wall area23, wherein thethreads74 are pulled and locked at a location outside of theheart wall22. In the particular embodiment depicted, thesuture clip140 is positioned at the apex28.
FIG. 8D illustrates a further embodiment of the invention, wherein thesuture threads74 are passed through theventricular septum26 and into theright ventricle16. Thesuture threads74 are then collected on the opposite (i.e., right ventricle) side of theventricular septum16, and eachthread74 may be pulled until the bulging is overcome. Thesuture threads74 can then be locked in the desired position by means of a locking mechanism, such as thesuture clip140 depicted. A similar treatment may also be applied to papillary muscles that have dislocated outwards due to myocardial infarction, thereby causing the mitral valve to leak. A thread or threads may be passed through the papillary muscle and then through the ventricular septum. As the thread or threads are tightened, they will cause inwards movement of the papillary muscle and thereby cause the mitral valve to be competent again, at which point the thread or threads can be locked on the right side of the septum by means of a locking mechanism, e.g., a knot or other fixation mechanism.
With reference now toFIG. 9, another alternative embodiment is illustrated wherein theanchor100 is deployed inside apapillary muscle60, and the elongate member72 (e.g., suture thread74) is locked via asuture clip140 inside theright atrium14, e.g., at a location close to theannulus51 of themitral valve50, thereby pulling thepapillary muscle60 toward theannulus51 and relieving pressure on thechordae tendinae58. Such a suture arrangement could treat left ventricular bulging, papillary muscle displacement and mitral regurgitation simultaneously.
With reference toFIG. 10A, another alternative embodiment is illustrated wherein ananchor100 is deployed in theheart wall22 just below themitral valve50, and the suture thread74 (or other elongate member) is locked via asuture clip140 in theright ventricle16 on theinterventricular septum26, with tension in thesuture thread74 pulling the posteriormitral leaflet54pfrom lateral towards theinterventricular septum26 and thereby shortening the antero-posterior diameter of themitral valve annulus51 to repair a mitral valve leak. Similarly (not shown) an anchor may be deployed in the heart wall adjacent the left atrium, just above or otherwise adjacent the mitral valve, adjacent to or in the mitral valve annulus, and the suture thread (or other elongate member) can be locked via a suture clip in the right atrium on the atrial septum, with tension in the suture thread pulling the posterior mitral leaflet from lateral towards the atrial septum and thereby shortening the antero-posterior diameter of the mitral valve annulus to repair a mitral valve leak.
With reference toFIG. 10B, yet another embodiment is illustrated wherein theanchor100 is located adjacent themitral valve50. The particular embodiment ofFIG. 10B depicts anchor deployment in theinterventricular septum26, although other deployment locations (such as in theheart wall22 in an area adjacent an upper portion of the left ventricle20) are also within the scope of the invention. Theanchor100 may be deployed by means of a catheter (such as thedelivery catheter122 fromFIGS. 5A-5D) from inside thecoronary sinus25. With the catheterdistal end120 positioned in a distal portion of the coronary sinus (or other desired deployment location) and the opening of thedistal end sheath124 held against the inner wall of the coronary sinus, theanchor100 can be advanced out of thedistal end sheath124 so theprongs108 are exposed to the coronary sinus wall and released to dig into theleft ventricular wall22 through the coronary sinus wall. Theelongate member72 in the form of asuture thread74 passes from theanchor100 and runs along the inside of the coronary sinus and extends out from theostium27 of thecoronary sinus25 into the right atrium, thereby at least partially encircling themitral valve annulus51. Thefree end76 of thesuture thread74 is locked in or outside of thecoronary sinus25 by means of a suture knot or lock (not shown), pulling the mitralvalve posterior leaflet54pfrom lateral towards theinteratrial septum24 and thereby shortening the antero-posterior diameter of themitral valve annulus51 to repair a mitral valve leak.
Those skilled in the art will appreciate that the treatments described herein may demand robust attachment strength. For example, when treating dilation of the left ventricle, the forces on the threads and the anchors are large due to the high blood pressure in the left ventricle and the high wall stress due to the large diameter of the bulging sack. In such cases, a two stage procedure might be preferred. For two-stage procedures (i.e., procedures where the anchor is deployed separately from the elongate member), the device may be provided with a coupling member to attach and/or release the elongate member to/from the anchor. The coupling member provides a point of attachment for connecting an elongate member, such as a suture thread, to the anchor during a second or later implantation stage. During the second stage, the thread portion may be delivered into the heart by means of a catheter-based technique, similar to that described above with respect toFIGS. 5A-5D. However, in the second stage of a multi-stage delivery, the elongate member is delivered into the heart using a delivery catheter and is subsequently coupled to the previously-deployed anchor or to a first part of another elongate member already attached to a coupling member of the pre-deployed anchor.
With reference now toFIG. 11, ananchor portion100 is shown some time after anchor deployment into themuscular heart wall22 of the left ventricle20 (i.e., after the first stage of the implantation procedure). After implantation in theheart12,endocardial tissue150 has grown over the exposedtubular portion152 of theanchor portion100 that is protruding from themuscular wall22 into theleft ventricle20, preferably leaving only theanchor coupling member110 exposed within theleft ventricle20. Simultaneously, inside theheart wall22 around the embedded portions of the anchor portion100 a scarring healing takes place, wherein fibrocytes create strong scarring tissue surrounding theprongs108, thereby integrating them with the muscle of theheart wall22 to create a very strong attachment. It has been found that adequate tissue overgrowth on the exposed areas of theanchor portion100 and the scar healing around theprongs108 may occur in two or three weeks. However, the amount of time required may depend on various factors, such as the location of theanchor portion100 within theheart12, the surface features or coatings of theanchor portion100, and finally the health status and other characteristics of the patient.
Thecoupling member110 provides a point of attachment for connecting an elongate member72 (such as thesuture threads74 and rod-like members86 previously described embodiments) during a second or later implantation stage. Note thatFIG. 11 does not depict an elongate member (such as asuture thread74 or rod-like member86 from earlier embodiments) as being present—the reason being that the elongate member is to be attached as a second or later stage of a multi-stage procedure. While a user may be able to couple the elongate member to the previously-deployed anchor portion by simply searching around the patient's heart, additional techniques can be used to facilitate this procedure. For example, both the coupling member on the anchor and an attachment mechanism of the thread portion may be magnetized, thereby allowing the two to be drawn together when in close proximity. In still another example, a vacuum-assisted connection can be used to facilitate connection of the elongate member to the anchor. As another example, anchor lines could be used, such as where an anchor line (e.g., a suture thread) is left secured to the coupling member of the anchor during the first implantation stage (i.e., anchor deployment) and left within the patient for use during the second stage (i.e., attaching the elongate member to the anchor). During the second implantation stage, the locking mechanism of the elongate member portion can be advanced along the guide element (e.g., originally-deployed suture thread or wire, etc.) until the locking mechanism reaches the coupling member of the previously-deployed anchor.
During the second or later stage, theelongate member72 may be delivered into the heart using a multi-stage procedure similar to that depicted inFIGS. 12A-12D, wherein ananchor portion100 is deployed in the first stage, and then theelongate member72 is advanced to the site and connected to theanchor portion70 in situ.
InFIG. 12A, ananchor deployment catheter160 is shown having adistal end162 advanced to a desired deployment site within theleft ventricle20. Theanchor portion100 is positioned at the anchor deployment catheterdistal end162, and more specifically is contained within the anchor deployment catheterdistal end162. Theanchor portion100 includesmultiple anchor members108 configured to expand outward and embed within the heart tissue when released from theanchor deployment catheter160, which can be accomplished by pushing theanchor portion100 out of theanchor deployment catheter160 and/or withdrawing theanchor deployment catheter160 from around theanchor portion100.
InFIG. 12B, theanchor portion100 has been deployed, with theanchor members108 embedded into the heart tissue in the lower portion of theleft ventricle20 adjacent the apex28. Theanchor portion100 has atop portion152 having ananchor connector110 configured to received a mating connector from an elongate member which will be deployed in the second stage (discussed below). Theanchor portion100 also includes ananchor line opening164, which is a loop or lumen through which ananchor line166 can be passed. Theparticular anchor line166 depicted inFIG. 12B is a line of suture that passes into the patient and into theheart12, passes through theanchor line opening164, and then passes back out of theheart12 and the patient to form a double suture line. As theanchor deployment catheter160 is removed from theheart12, theanchor line166 is left trailing from theanchor portion100 and out of theheart12 and patient. While allowing theanchor portion100 to heal in over some time, the free ends of the anchor line might also be left under the skin of the patient and then retrieved when needed.
FIG. 12C depicts the second stage of the deployment procedure, wherein theelongate member72 is advanced into theheart12 and secured to theanchor portion100. Asecond deployment catheter170, to which is secured anelongate member72, is advanced to the area in theleft ventricle20 at or adjacent the previously-deployedanchor portion100. In the particular embodiment depicted, thesecond deployment catheter170 is an over-the-wire type catheter having an inner lumen configured to permit theanchor line166 to slidingly pass therethrough. Note, however, that a so-called rapid-exchange type of delivery catheter could also be used. Thesecond deployment catheter170 includes a canopy container in the form of aside pocket174 configured to contain and restrain theelongate member72 during delivery.
As depicted inFIG. 12C, thesecond deployment catheter170 is advanced along theanchor line166 to theanchor portion100. Theelongate member72 includes adistal end176 having aconnector178 configured to be secured to ananchor portion connector110 on the exposedupper surface152 of theanchor portion100. As thesecond deployment catheter170 is advanced along theanchor line166, the elongate body portiondistal end176 andconnector178 will be led into alignment and contact with theanchor portion connector110. When the elongatebody portion connector178 contacts theanchor portion connector110, the twoconnectors110,178 are connected together. Note that many different types of connectors are within the scope of the invention, and the particular connectors used with a particular device may be a matter of choice. The connectors may be snap-type or quick-connect connections which automatically connect when the two connectors are brought into contact. The connectors may be manually operated, and/or may include a release device to permit disconnection at a later time.
Connection of the twoconnectors110,178 effectively secures theanchor portion100 to theelongate member72. Once the twoconnectors110,178 are connected, thesecond deployment catheter170 can be withdrawn, which will release theelongate member72 from theside pocket174 to deploy theelongate member72, as depicted inFIG. 12D. In the particular method depicted, theanchor line166 is still depicted in position passing through the anchor line loop164 (although theanchor line166 could have been removed along with, or even prior to, removal of the second deployment catheter170). Theanchor line166 can now be removed, which in the case of the double suture line depicted can involve releasing one end of the line that passes outside of the heart, and pulling on the other end passing outside the heart. The loose end of the double suture line will thus be pulled into theheart12 and will be pulled out of theanchor line loop164, thus releasing theanchor line166 from theanchor portion100. Thefree end76 of theelongate member72 can be secured to the desired tissue (e.g., a valve leaflet) to complete deployment of thedevice10. Theopening92 through which thecatheters160,170 were advanced into and removed from theheart12 can be closed using a purse-string suture94.
Note that a two-stage deployment device and method such as that depicted inFIGS. 12A-12D could be useful for situations where a user may desire to replace an initially-deployed elongate member. For example, if after the device is entirely deployed in a patient's heart, a user may determine that the initially-deployed elongate member is not of the optimal size/configuration or not optimally secured to desired tissue. Such situations may arise where one or more portions of the patient's heart (e.g., the valve, etc.) has deformed since the initial deployment procedure. In such a situation, a user could remove the initially-deployed elongate member while leaving the anchor portion in place. The user could then attach another elongate member to the anchor portion, and secure the free ends of the elongate member as desired. Alternatively, the user could simply leave the initial anchor portion in place without attaching another elongate member thereto. The user could also deploy a second elongate member using a second anchor portion.
Deployment of the device and/or of specific elements thereof, including navigation of the elongate member to connect to a previously-deployed anchor, can be facilitated with cameras, X-rays, or similar techniques which allow the user to visualize the device elements within the patient.
FIG. 13A depicts asuture deployment device200 for use in deploying an elongated member, such as a suture line, into a valve leaflet. Thesuture deployment device200 comprises anelongated body202, aproximal end204 having ahandle206, and adistal end208.
FIGS. 13B-13C depict a close-up views of thedistal end208 of thesuture deployment device200. Avacuum port210 is positioned on a side of thedistal end208 and is in fluid communication with asuction lumen212 passing the length of the suture deployment device and configured to be attached at the deviceproximal end204 to a vacuum source (not shown). The vacuum applied to thevacuum port210 is controlled by a user via one ormore controls214 positioned on thehandle206. Twoneedles216a,216bare positioned inneedle lumens218a,218band configured to be advanced and retracted across thevacuum port210. Theneedles216a,216bmay be independently controlled for separate advancement and retraction. In the particular embodiment depicted, theneedles216a,216bare coupled to or otherwise in communication withactuators220a,220blocated on thedevice handle206. The forward and rearward movement of theactuators220a,220bresults in corresponding longitudinal movement of theirrespective needles216a,216b, thereby permitting the first andsecond needles216a,216bto extend from and retract into the first andsecond needle lumens218a,218bvia first andsecond needle ports222a,222b. Those skilled in the art will appreciate that the first andsecond needles216a,216bmay be capable of individual and/or simultaneous movement.
Aguidewire lumen224 configured to receive aguidewire226 or similar guide line therein may be positioned in thesuture deployment device200, and may pass the length of the device (in a so-called over-the-wire configuration) or may pass only through a portion of the distal end and exit through a side just proximal of the distal end (in a so-called rapid-exchange configuration).
As depicted inFIGS. 13B-13C, first and second needle-receivingports228a,228bmay be positioned within or proximate thevacuum port210 and co-aligned with and opposing the first andsecond needle ports222a,222b, respectively. The first needle-receivingport228ais in communication with thefirst suture lumen230aand contains afirst needle catch232aattached to thefirst suture portion234athat passes into thefirst suture lumen230a. Similarly, the second needle-receivingport228bis in communication with thesecond suture lumen230band contains asecond needle catch232battached to thesecond suture portion234bthat passes into thesecond suture lumen230b.
Depending on the particular application, the first andsecond suture portions234a,234bmay be entirely separate suture lines, or may comprise opposing portions of a single common suture line that forms a loop between thefirst needle catch232aand thesecond needle catch232b. If the first andsecond suture portions234a,234bare part of a single common suture line, the first and second needle-receivingports228a,228bmay form a single opening, and the first andsecond suture lumens230a,230bmay form a single lumen, in order to permit the single common suture line loop to exit freely from thesuture deploying device200.
FIGS. 14A-D depict a method of using thesuture deployment device200 ofFIGS. 13A-13C to deploy suture line through a valve leaflet to create a replacement chordae tendinae. InFIG. 14A, thesuture deployment device200 is introduced into a patient's body until thedistal end208 is advanced into theheart12, and more specifically (in the particular embodiment depicted) to a position where thevacuum port210 is adjacent the posteriormitral valve leaflet54p, in which one of theseveral chordae58 has ruptured into twoseparate pieces58a,58b.
In the particular embodiment depicted inFIG. 14A, thesuture deployment device200 has been advanced percutaneously in a trans-septal approach, using aguide catheter240, via theinferior vena cava32 andright atrium14 and through anopening242 in the atrial septum24 (or through a patent foramen ovale, not shown) into theleft atrium18 to the desired position adjacent thevalve leaflet54p, which in the particular embodiment depicted is a posterior leaflet of themitral valve50. Note, however, that other approaches are also within the scope of the invention, including other percutaneous and minimally invasive approaches, such as approaches via the aorta, superior vena cava, or directly through the outer heart wall, etc. Note also that the same procedure may be used for attachment to an anterior leaflet of the mitral valve.
InFIG. 14B, thesuture deployment device200 uses thevacuum port210 to grasp thevalve leaflet54p. With thevalve leaflet54pfirmly held by thevacuum port210, thesuture deployment device200 advances aneedle216athrough thevalve leaflet tissue244, with theneedle216aengaging against and becoming secured to aneedle catcher232aon the far side of thevalve leaflet tissue244 andvacuum port210, as depicted inFIG. 14C. Theneedle232ais then withdrawn back through thevalve leaflet tissue244, thus dragging theneedle catcher232aand attachedsuture line portion234aback through thevalve leaflet tissue244, as depicted inFIG. 14D. The devicedistal end208 is then moved away from thevalve leaflet54p, with thesuture line portion234atrailing out of thedevice200, as depicted inFIG. 14E.
Similar devices to that depicted and described with respect toFIGS. 14A-14E are depicted and described in pending U.S. patent application Ser. No. 10/389,721, filed on Mar. 14, 2003 and entitled “Mitral Valve Repair System and Method for Use,” the entire contents of which are hereby incorporated by reference.
FIG. 15 depicts an embodiment wherein ananchor100 has previously been deployed in a papillary muscle60 (e.g., using devices and methods such as those previously described with respect toFIG. 11, etc.), with an elongate member portion in the form of a papillary-anchoredsuture line250 passing from theanchor100 and out of the patient via theleft atrium18,atrial septum24,right atrium14, andinferior vena cava32, i.e., along the same path through which thesuture deployment device200 was advanced inFIGS. 14A-14E. In such an embodiment, the previously-deployed papillary-anchoredsuture line250 can actually serve as a guide line over which thesuture deployment device200 can be advanced similar to the technique ofFIGS. 14A-14E, but with the papillary-anchoredsuture line250 serving as a guide line there may be no need for aguide catheter240 such as that depicted inFIGS. 14A and 14E.
With a previously-deployedanchor100 and papillary-anchoredsuture line250 already in place as inFIG. 15, thesuture deployment device200 can, after having passed a leaflet-securedsuture line234 through avalve leaflet54p, be withdrawn from the patient as shown, with the leaflet-securedsuture line234 trailing out of thesuture deployment device200 and eventually out of the patient once the suture deployment device is completely withdrawn from the patient.
InFIGS. 16A-16D, an embodiment of a suture securing and cuttingdevice260 is depicted. Thefastener catheter260 has a generally tubularmain body262, aproximal end264, and adistal end266. Theproximal end264 includes ahandle knob268. Thedistal end266 includes asuture clip270 positioned thereon. Thefastener catheter260 may be manufactured in a variety of shapes, sizes, lengths, widths, and biologically-compatible materials as desired for a particular application.
The generally tubularmain body262 has a longitudinalinner lumen272 therethrough which terminates in adistal opening274. A longitudinally slidableinner body276 is slidably positioned within themain body262. Theinner body276 includes an inner tubular memberdistal end278 which extends out of the main bodydistal opening274. The inner tubular memberdistal end278 itself includes an inner tubular memberdistal opening280, which leads to aninner body lumen282. These and other features are depicted in additional detail inFIGS. 16B-16D, which illustrate (in exploded fashion inFIGS. 16B-16C, and assembled inFIG. 16D), distal portions of thefastener catheter260.
Theinner body276 includes asuture recess284 formed in the side thereof, which in turn is in communication with theinner body lumen282.Inner body276 also includes apin286 extending radially outward therefrom. Themain body262 has acutting recess288 formed in an axial side thereof and a cuttingmember290 which, in the embodiment depicted, is on a proximal edge of cuttingrecess288. A pin recess in the form of aslot292 extends parallel to the axis of themain body262 and radially through tomain body lumen272. Theslot292 is thus configured to receivepin286 in sliding relation.
InFIG. 16D, theinner body276 is slidably positioned withinmain body262, such thatsuture recess284 is in alignment with cuttingrecess288.Pin286 is in slidable communication withslot292 thereby permitting relative linear motion, but preventing relative rotational motion, betweeninner body276 andmain body262. Aclip270 is positioned on the inner bodydistal end278, which protrudes from the main bodydistal opening274. Theclip270 includes a clipdistal opening294, clipproximal opening296, andengagement members298. As depicted inFIG. 16D, theclip270 has been placed on inner memberdistal end278 by deflecting theengagement members298 radially outward until they can be placed around the outer circumference of inner bodydistal end278. Accordingly, theclip270 is secured to the inner bodydistal end278 by means of the frictional engagement between theengagement members298 and the outer surface of inner bodydistal end278.Suture234 extends through thefastener clip270, with suture leads234aand234bextending through the clipdistal opening294,engagement members298, andproximal opening296, passing through inner memberdistal opening280 andinner member lumen282, exiting theinner member276 viasuture recess284, and exiting the side ofmain body262 through cuttingrecess288.
Once theclip270 is advanced to a desired position on thesuture line234, theinner member276 can be retracted with respect to themain body member262, thereby causing the inner bodydistal end278 to be pulled inside themain body member262. Theclip270 will thus be pushed off of the inner bodydistal end278 by themain body262, at which point theclip engagement members298 move inwardly to block the clipproximal opening296 and thereby lock theclip270 onto thesuture234. The retraction of theinner member276 with respect to themain body member262 also causes thesuture portions234a,234bto be pinched between theinner member opening284 and the cutting member190, so that thesuture portions234a,234bare cut by the cuttingmember290.
Similar devices to that depicted and described with respect toFIGS. 16A-16D are depicted and described in pending U.S. patent application Ser. No. 10/389,721, filed on Mar. 14, 2003 and entitled “Mitral Valve Repair System and Method for Use”; pending U.S. patent application Ser. No. 11/174,397, filed on Jun. 30, 2005 and entitled “System, Apparatus, and Method for Fastening Tissue”; pending U.S. patent application Ser. No. 11/345,208, filed on Jan. 31, 2006 and entitled “System, Apparatus, and Method for Fastening Tissue”; and pending U.S. patent application Ser. No. 11/746,009, filed on May 8, 2007 and entitled “Suture-Fastening Clip”; the entire contents of each of which are hereby incorporated by reference.
FIGS. 17A-17C depict a method of securing the deployedsuture lines234,250 together at a desired length in order to create a replacement chordae tendinae. InFIG. 17A, the suture securing and cuttingdevice260 is shown with thedistal end266 being advanced along the previously-deployedsuture lines234,250, with the papillary-anchoredsuture line250 serving to guide the suture securing and cuttingdevice260 into the patient'sheart12 andleft ventricle20. As the suture securing and cuttingdevice260 is advanced along the previously-deployed papillary-anchoredsuture line250, the user (such as a surgeon or cardiologist) pulls on the proximal end of the papillary-anchored suture line250 (which is positioned outside of the patient) to maintain slight tension as the suture securing and cuttingdevice260 is advanced into theleft ventricle20. The user may also pull on the proximal ends of the leaflet-securedsuture line234 to prevent it from being pushed into the patient as the suture securing and cutting device is advanced.
InFIG. 17B, the suture securing and cutting devicedistal end266, withsuture securing clip270 thereon, is depicted advanced to a desired location in the left ventricle. The user pulls on the papillary-anchoredsuture line250 and/or on the leaflet-securedsuture line234 to achieve a replacement chordae tendinae of a desired length. While adjusting the length of the replacement chordae tendinae, the user can monitor the heart function using various devices known in the art, such as fluoroscopy, radiography, ultrasound, etc. In one example, the user can verify the effectiveness of the replacement chordae tendinae length by monitoring blood flow using radiopaque dyes combined with fluoroscopy or by means of ultrasound. When the user sees via the heart function monitoring system(s) that the heart valve is functioning as desired, the user then knows that the replacement chordae tendinae (formed by thesutures234,250) is at the appropriate length. The user can then activate the suture securing and cuttingdevice266 to release thesuture clip270 so that it secures thesutures234,250 at the desired position, thereby forming the desired replacement chordae tendinae. The user also activates the suture securing and cuttingdevice266 to cut the excess suture portions away adjacent theclip270.
FIG. 17C depicts theclip270 deployed and theexcess portions234e,250e(i.e., portions proximal of the clip270) of thesuture lines234,250 having been cut. The suture securing and cuttingdevice266 is being withdrawn from the patient, along with the excess cut-offsuture portions234e,250e. The deployedsuture lines234,250 are held firmly by theclip270 to serve as a replacement chordae tendinae.
In a further embodiment of the invention, thesuture deployment device200 can be used to secure thesuture line234 directly to the papillary muscle or other heart tissue, and/or to a previously-deployed anchor. For example, in one such embodiment the suture deployment device is used to deploy thesuture line234 through thepapillary muscle60, as depicted and described with respect toFIGS. 18A-B.
FIG. 18A depicts thesuture deployment device200 having already passed a one portion ofsuture line234athrough avalve leaflet54p(as was depicted inFIGS. 14A-14E), and then being maneuvered so that thedistal end208 andvacuum port210 positioned adjacent apapillary muscle60 and the vacuum activated, so that thepapillary muscle60 has been grasped and held by thevacuum port210. As the suture deployment devicedistal end208 is moved from its previous position adjacent thevalve leaflet54p(i.e., the position depicted inFIGS. 14A-D), the leaflet-securedsuture line234aplays out from thesuture deployment device200. A needle from the suture deployment device is used to pass asecond suture line234bthrough thepapillary muscle60, using an apparatus and technique such as that depicted inFIGS. 14B-14D that was used to pass the leaflet-securedsuture line234athrough theleaflet54p. For example, using a device such as that depicted inFIGS. 13A-13C,needle216acould be used to pass the leaflet-securedsuture line234athrough theleaflet54p, whileneedle216bcould be used to pass the papillary-securedsuture line234bthrough a portion of thepapillary muscle60.
Once the papillary-securedsuture line234bis secured to thepapillary muscle60, the vacuum can be discontinued so that thepapillary muscle60 is released from thevacuum port210. As depicted inFIG. 18B, thesuture deployment device200 can then be withdrawn from the patient'sheart12, with the papillary-securedsuture line234band leaflet-securedsuture line234atrailing out from the suture deployment devicedistal end208 and eventually trailing out of the patient as thesuture deployment device200 is completely withdrawn. A suture clip can then be advanced over thesuture line portions234a,234band secured at a desired place thereon to create a replacement chordae of the desired length, using devices and methods such as those depicted in FIGS.16 and17A-17C.
Note that the deployment devices and methods depicted and described above can be varied and still fall within the scope of the invention. For example, the leaflet-secured suture line(s) can be secured to the leaflet before, after, or simultaneously with deployment of the papillary-secured suture line(s). The suture deployment device could be used to secure a papillary-secured suture line or lines directly to the papillary muscle, or to an anchor or other device deployed in the papillary muscle. For example, the suture deployment device may have a magnet near its distal end to assist in guiding the suture deployment device to an anchor that has a magnet. Also note that the suture deploying method and device can vary. For example, the suture deploying device could be configured to drive a pledget, barb-like device, or similar structure into the leaflet, papillary muscle, and/or anchor, with a suture line being secured to the pledget, barb-like device, or similar structure. The anchor, suture clip, suture lines, suture deployment device, and/or suture securing/cutting device may include one or more visualization references. For example, visualization references in the form of radiopaque marker bands may be positioned on or adjacent the distal end of the suture deployment device and/or suture securing/cutting device, and/or on the anchor, etc. The radiopaque marker bands are viewable under a fluoroscope, so that a surgeon or other user can use a fluoroscope to visualize the positions of the devices and anchors within the patient and with respect to any devices present, such as guidewires, etc. Depending on the particular application, the visualization markers on a particular device may be identical or may be different from each other. Radiopaque marker bands or other visualization references that provide different radiopaque or other visualization signatures permit a user to differentiate between particular elements (e.g., between an anchor and a suture deployment device, etc.). The efficacy of an implant (or implants) and its deployed position can be confirmed and monitored at various times during and after the deployment procedure via various techniques, including visualization methods such as fluoroscopy.
Various materials could be used to form the devices of the invention, including the anchors, suture lines, suture deployment devices, and other system components.
ANIMAL EXPERIMENTS: Two sixty kilograms adult sheep were sedated, anesthetized and connected to mechanical ventilation. A tracheal tube was inserted and the sheep put on the right side on an operating table. Under sterile conditions the chest was opened under the 5thrib and the pericardium was opened. A purse-string suture with a tourniquet was put on the left atrial appendage. A device of the type described above was inserted through the purse-string suture and advanced to the apex of the left ventricle. At this location, the anchor was deployed. Four weeks after the procedure, the sheep were taken back to the animal facility, anesthetized, and sacrificed by means of high dose potassium. The hearts were extracted and inspected. The anchors were found not to have penetrated the left ventricular wall and had remained in the position where they were placed during surgery. At gross inspection the anchors had healed smoothly in normal thin scar tissue and were covered by a thin layer of endothelium. A pull test was performed by pulling in the thread. At a pulling force of 1.6 Kilogram, the anchor tore out the scar tissue with surrounding heart muscle while still being intact inside the chunk of muscle. Thus one could conclude that the healing in into the left ventricular wall was stronger than the muscle itself. Using a third sheep of sixty kilograms, the same surgical procedure was performed. This time the animal was sacrificed immediately and the heart extracted. A pulling test now revealed a fixation force corresponding to a traction of 800 grams before the arms of the anchor bent back and slid out of the still intact muscle. The 800 gram fixation force is redundant to what is needed for strength when attaching a chordae tendinae to a papillary muscle and more than sufficient for treating a dilated ventricular wall.
Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed invention. For example, although the above devices and methods are described for use in a particular manner, the devices and methods described herein could be used in a variety of different methods of use, such as, for example, via open heart surgical access, via a beating heart surgical access (e.g., a trans-apical approach) and via a percutaneous approach. As a further example, it will be recognized that the embodiments described above and aspects thereof may also be used to treat a tricuspid valve or other valves in substantially similar manner. In addition, many modifications may be made to adapt a particular situation or device to the teachings of the invention without departing from the essential scope thereof. Furthermore, the devices and methods could be used for entirely other purposes wherein it may be advantageous to attach a suture to tissue with an anchor rather than using a needle and thread. Examples of such procedures include wound closure and treating organ prolapse. Furthermore, if desired, the anchor and/or thread may be configured to be resorbable such that they dissolve within the body over time. Accordingly, it is to be understood that the drawings and descriptions of specific embodiments herein are proffered by way of example to facilitate comprehension of the invention, and should not be construed to limit the scope thereof.