Abstract:
A device for repairing a heart valve comprises an implantation instrument. The implantation instrument comprises a first support ring, and a second support ring connected to said first support ring to form a coiled configuration. The first support ring is configured to abut one side of the valve and the second support ring is configured to abut an opposite side of the valve to thereby trap a portion of the valve tissue therebetween. The device further comprises an annuloplasty implant adapted to be attached to the heart valve annulus in order to reshape the annulus and allow the leaflets to open and close properly. The annuloplasty implant is connected to the implantation instrument for insertion to the annulus.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention generally relates to heart valve repair and replacement techniques and annuloplasty devices. More specifically, the invention relates to the repair of heart valves having various malformations and dysfunctions.  
       BACKGROUND OF THE INVENTION  
       [0002]     Diseased mitral and tricuspid valves frequently need replacement or repair. The mitral and tricuspid valve leaflets or supporting chordae may degenerate and weaken or the annulus may dilate leading to valve leak (insufficiency). The leaflets and chords may become calcified and thickened rendering them stenotic (obstructing forward flow). Finally, the valve relies on insertion of the chordae inside the ventricle. If the ventricle changes in shape, the valve support may become non-functional and the valve may leak.  
         [0003]     Mitral and tricuspid valve replacement and repair are traditionally performed with a suture technique. During valve replacement, sutures are spaced around the annulus (the point where the valve leaflet attaches to the heart) and then the sutures are attached to a prosthetic valve. The valve is lowered into position and when the sutures are tied, the valve is fastened to the annulus. The surgeon may remove all or part of the valve leaflets before inserting the prosthetic valve. In valve repair, a diseased valve is left in situ and surgical procedures are performed to restore its function. Frequently an annuloplasty ring is used to reduce the size of the annulus. The ring serves to reduce the diameter of the annulus and allow the leaflets to oppose each other normally. Sutures are used to attach a prosthetic ring to the annulus and to assist in plicating the annulus.  
         [0004]     In general, the annuloplasty rings and replacement valves must be sutured to the valve annulus and this is time consuming and tedious. If the ring is severely malpositioned, then the stitches must be removed and the ring repositioned relative to the valve annulus during restitching. In other cases, a less than optimum annuloplasty may be tolerated by the surgeon rather than lengthening the time of the surgery to restitch the ring.  
         [0005]     During heart surgery, a premium is placed on reducing the amount of time used to replace and repair valves as the heart is frequently arrested and without perfusion. It would therefore be very useful to have a method to efficiently attach a prosthesis into the mitral or tricuspid valve position.  
       SUMMARY OF THE INVENTION  
       [0006]     It is an object of the invention to provide a more reliable and more easily accomplished valve repair. It is a specific object of the invention to facilitate insertion of an annuloplasty implant.  
         [0007]     These and other objects of the invention are accomplished by means of a device, a kit and a method according to the independent claims. Preferred embodiments of the invention are apparent from the dependent claims.  
         [0008]     Thus, according to a first aspect of the invention, a device is provided for repairing a heart valve comprised of valve tissue including an annulus and a plurality of leaflets for allowing and preventing blood flow through a patient&#39;s heart. The device comprises an implantation instrument, which comprises a first support ring, and a second support ring connected to the first support ring to form a coiled configuration. The first support ring is configured to abut one side of the valve and the second support ring is configured to abut an opposite side of the valve to thereby trap a portion of the valve tissue, that is, annulus tissue and/or leaflet tissue, therebetween. The device further comprises an annuloplasty implant adapted to be attached to the heart valve annulus in order to reshape the annulus and allow the leaflets to open and close properly.  
         [0009]     The implantation instrument is applied to the heart valve in a much easier manner than conventionally utilized annuloplasty rings. By means of the implantation instrument it is possible to fixate the valve annulus and primarily reshape it. This primary reshaping of the valve annulus facilitates attachment of the annuloplasty implant to the valve annulus. There is merely a need for a slight further reshaping of the valve annulus by the attachment of the annuloplasty implant in order to achieve the desired shape of the valve annulus. Since the attachment of the annuloplasty implant need not dramatically change the shape of the valve annulus, the possibility of correctly positioning the annuloplasty implant is greatly increased. This implies that there is a very slim risk that the annuloplasty implant will need to be repositioned. Further, by means of the device the desired reshaping of the valve annulus may in most cases be achieved.  
         [0010]     The invention contemplates various embodiments of the device, including embodiments for catheter-based surgery and embodiments for open heart surgery.  
         [0011]     The first and second support rings may have generally triangular-shaped cross sections with flat sides opposing one another and trapping valve tissue therebetween.  
         [0012]     At least the opposed surfaces of the first and second support rings may be roughened, such as by the use of fabric, coatings, knurling or the like to facilitate better engagement and retention of the support rings on the valve tissue. The opposed surfaces may be roughened in a pattern extending along the longitudinal direction of the rings. This implies that the roughened surface will serve to prevent slippage of tissue through the ring while presenting a low friction for the ring to be turned into position abutting the valve. The implantation instrument may have an inherent shape where the first and second rings contact or nearly contact each other. Thus, the implantation instrument will present a spring force pushing the first and second rings towards each other. The spring force will make the first and second rings fixating valve tissue between them.  
         [0013]     Preferably, the first and second support rings are formed integrally from a coiled rod, such as a metallic rod, with one end of the rod formed as a leading end and one end formed as a trailing end. These ends may be bent in opposite directions so that the leading end may be directed through the valve tissue and the trailing end may be grasped by an appropriate surgical implement. A carrier may be used to rotate the implantation instrument into position on opposite sides of the valve annulus. As another alternative, the carrier may be coil-shaped and the implantation instrument may be rotated into place on only one side of the valve annulus similar to conventional rings. The carrier may also be rotated in opposite direction for withdrawing the implantation instrument. The first and second support rings may be adjustable in diameter to allow adjustment of the valve annulus.  
         [0014]     The annuloplasty implant may have an arcuate shape conforming to a desired arcuate shape of a portion of the annulus. The annuloplasty implant may then be attached to the portion of the valve annulus for reshaping the valve annulus. The desired reshaping of the valve annulus may be achieved by the annuloplasty implant reshaping only a portion of the valve annulus. Thus, the annuloplasty implant may be C- or U-shaped. The annuloplasty implant may alternatively have a ring-shape conforming to the desired shape of the annulus. The annuloplasty implant may thus be attached to the valve annulus forcing it to assume the desired shape.  
         [0015]     The annuloplasty implant may be removably attached to the second support ring of the implantation instrument. The annuloplasty implant may then be detached from the implantation instrument after being attached to the valve annulus. The implantation instrument may thereafter be removed from the patient. The annuloplasty implant may be attached to the second support ring by means of a removable suture. The suture may be cut in order to detach the annuloplasty implant from the implantation instrument.  
         [0016]     According to a second aspect of the invention, a kit is provided for repairing a heart valve comprised of valve tissue including an annulus and a plurality of leaflets for allowing and preventing blood flow. The kit comprises an implantation instrument, which comprises a first support ring, and a second support ring connected to the first support ring to form a coiled configuration. The first support ring is configured to abut one side of the valve and the second support ring is configured to abut an opposite side of the valve to thereby trap a portion of the valve tissue therebetween. The kit further comprises an annuloplasty implant adapted to be attached to the heart valve annulus in order to reshape the annulus and allow the leaflets to open and close properly.  
         [0017]     The annuloplasty implant need not be attached to the implantation instrument for being inserted to the heart valve. The implantation instrument may provide the primary reshaping of the valve annulus. The annuloplasty implant may then be separately inserted to permanently reshape the valve annulus. The correct positioning of the annuloplasty implant is now easily achieved since the primary reshaping of the valve annulus provided by the implantation instrument clearly indicates how the annuloplasty implant should be attached to the valve annulus.  
         [0018]     According to a third aspect of the invention, a method is provided for repairing a heart valve comprised of valve tissue including an annulus and a plurality of leaflets for allowing and preventing blood flow. The method comprises inserting an implantation instrument comprising a first and a second support ring connected to each other to form a coiled configuration, said instrument being inserted such that valve tissue is trapped between the first and second support rings, attaching an annuloplasty implant to the annulus in order to reshape it, and removing the implantation instrument.  
         [0019]     The step of inserting the instrument may comprise temporarily reshaping the annulus to facilitate attachment of the annuloplasty implant to the annulus. Thus, the implantation instrument will guide the positioning of the annuloplasty implant.  
         [0020]     The step of inserting may further comprise inserting a first end of the first support ring through a portion of the valve tissue, rotating the implantation instrument to position the first support ring on a first side of the valve, and positioning the second support ring on an opposite second side of the valve. The first and second support ring are thus easily applied on opposite sides of the valve.  
         [0021]     Various additional objectives, advantages and features of the invention will become more readily apparent to those of ordinary skill in the art upon review of the detailed description of the illustrative embodiments. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]      FIG. 1  schematically illustrates a patient with a heart shown in cross section and a device of the present invention schematically illustrated as supporting the mitral valve.  
         [0023]      FIG. 1A  is a cross sectional view of the left ventricle showing the mitral valve and a device of the invention in perspective.  
         [0024]      FIG. 2  is a perspective view of a device according to an embodiment of the invention.  
         [0025]      FIG. 3  is a cross sectional view of the device in  FIG. 2 .  
         [0026]      FIGS. 4   a - b  are partially sectioned perspective views of the mitral valve and the device of the invention during implantation of an annuloplasty implant of the device.  
         [0027]      FIG. 5  is a partially sectioned perspective view showing the device of the invention when the implantation instrument has been turned into position.  
         [0028]      FIG. 6  is a cross-sectional view illustrating primary reshaping of the valve.  
         [0029]      FIG. 7  is a partially sectioned perspective view showing the device when the annuloplasty implant is being attached to the valve annulus.  
         [0030]      FIG. 8  is a perspective view showing the device after implantation is completed. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0031]      FIG. 1  illustrates a patient  10  having a heart  12  shown in cross section including a left ventricle  14  and a right ventricle  16 . The concepts of the present invention are suitable to be applied, for example, to a mitral valve  18  which supplies blood into left ventricle  14 . Mitral valve  18 , as better shown in  FIG. 1A , includes an annulus  20  and a pair of leaflets  22 ,  24  which selectively allow and prevent blood flow into left ventricle  14 . It will be appreciated that the term annulus tissue is used extensively throughout this disclosure in reference to the drawings, however, the inventive principles are equally applicable when referring to other valve tissue such as leaflet tissue or other attached vessel tissue. Leaflets  22 ,  24  are supported for coaptation by chordae tendinae or chords  26 ,  28  extending upwardly from respective papillary muscles  30 ,  32 . Blood enters left ventricle  14  through mitral valve  18  and is expelled during subsequent contraction of heart  12  through aortic valve  34 . It will be appreciated that the present invention is applicable to tricuspidal heart valves as well.  
         [0032]     A preferred device of the present invention is shown in  FIGS. 2 and 3 . The device comprises an implantation instrument  40  which comprises a first and a second support ring  42 ,  44  assuming a coiled configuration in the form of a spiral or keyring-type configuration. Any suitable medical grade material(s), such as medical grade metals or plastics, may be used to form the implantation instrument  40 . The device is shown in cross section in  FIG. 3 . The implantation instrument  40  has a traditional cross sectional shape associated with a keyring. In this embodiment flat, opposed surfaces  46  are arranged to trap valve annulus tissue  20  therebetween. The opposed surfaces  46  may also be roughened in order to improve engagement with the valve annulus  20 .  
         [0033]     An annuloplasty implant  50  is attached to the second support ring  44  of the implantation instrument  40 , by means of sutures or clips. The annuloplasty implant  50  may be any type of annuloplasty ring, such as the CG Future™ Annuloplasty System manufactured by Medtronic, Inc., the SJM Tailor® Annuloplasty Ring or the SJM Tailor® Flexible Annuloplasty Band manufactured by St. Jude Medical, Inc., the Sovering™ manufactured by Sorin Group, the Carpentier-McCarthy-Adams IMR ETlogix Annuloplasty Ring® or the Carpentier-Edwards Classic Annuloplasty Ring® manufactured by Edwards Lifesciences Corporation, which annuloplasty ring may form a complete ring-shape or an arcuate shape. The annuloplasty implant  50  is adapted to be attached to the valve annulus  20  by means of suture threads, as will be explained in further detail below. The annuloplasty implant  50  has a shape conforming to a desired shape of the valve annulus  20 . Thus, when attached to the valve annulus  20 , the annuloplasty implant  50  will reshape the valve annulus  20  to a desired shape. The annuloplasty implant  50  is non-stretchable lengthwise, which implies that when attached to the valve annulus it will not allow dilatation of the annulus. However, the annuloplasty implant may be flexible to change its shape while maintaining its length to allow the normal movements of the valve annulus  20  during a heart cycle. The annuloplasty implant  50  may have sections of differing rigidity and flexibility to comply with the normal movements of the valve annulus  20  during the heart cycle.  
         [0034]     Referring now to  FIGS. 4-7 , a method for repairing a heart valve by means of the device will be described. First, access to the heart valve is achieved by conventional techniques, including arresting the heart and opening the chest. In  FIG. 4   a , the device is shown when being inserted to the mitral valve  18 . The implantation instrument  40  is being carried on a coil-shaped carrier  52 , which is connected to a stem for remote control of the positioning of the carrier  52 . An end of the first support ring  42  is brought to a corner of the opening between the leaflets  22 ,  24  of the mitral valve  20 , as shown in  FIG. 4   b . The end is led through the opening and the coil-shaped carrier  52  is turned 360 degrees. Thus, the first support ring  42  will be rotated into place on one side of the valve  18 , whereas the second support ring  44  is placed on the opposite side of the valve  18 . In this way, the implantation instrument  40  is arranged in engagement with the valve  18 , as shown in  FIG. 5 .  
         [0035]     The leaflets  22 ,  24  may now be drawn towards each other through the pinch of the support rings  42 ,  44 , as illustrated in  FIG. 6 . The leaflets are drawn through the pinch by means of a forceps instrument  54 . The support rings  42 ,  44  may flex away from each other to allow drawing leaflets  22 ,  24  through the pinch and towards each other for preventing the leaflets  22 ,  24  to slip back. The valve annulus  20  may in this way be reshaped and be temporarily held in the new shape by means of the implantation instrument  40 . The support rings  42 ,  44  may have roughened, opposed surfaces  46  to better keep the leaflets  22 ,  24  from slipping through the pinch and to hold the valve annulus  20  in its reshaped form.  
         [0036]     The annuloplasty implant  50 , which has been carried into position by means of the second support ring  44 , may now be attached to the valve annulus  20  for achieving a permanent reshaping of the annlus  20 . Since a primary reshaping has already been made, the positioning of the annuloplasty implant  50  is facilitated. The annuloplasty implant  50  is sutured to the valve annulus, as illustrated in  FIG. 7 , showing a completed suture  60  attaching the annuloplasty implant  50  to the valve annulus  20  and showing a suture  62  being performed. In this way, the annuloplasty implant  50  is firmly attached to the valve annulus  20  for keeping the valve annulus  20  in its reshaped form. The leaflets  22 ,  24  may also or alternatively be drawn towards each other through the pinch of the support rings  42 ,  44  during suturing of the annuloplasty implant  50 .  
         [0037]     When the annuloplasty implant  50  has been firmly attached to the valve annulus  20 , the annuloplasty implant  50  is released from the implantation instrument  40 . The sutures holding the annuloplasty implant  50  attached to the second support ring  44  are cut in order to release the annuloplasty implant  50  from the implantation instrument  40 . Now, the implantation instrument  40  may be withdrawn. The carrier  52  is turned 360 degrees in order to rotate the first support ring  42  to be retracted through the opening between the leaflets  22 ,  24 . Thereafter, the carrier  52  with the implantation instrument  40  may be retracted from the patient. As shown in  FIG. 8 , the annuloplasty implant  50  is now left in the patient holding the valve annulus  20  in a reshaped form such as to function normally.  
         [0038]     As an alternative, the implantation instrument  40  does not carry the annuloplasty implant  50 . In this case, the implantation instrument  40  is inserted into position first. This positioning of the implantation instrument  40  may be performed as described above with reference to  FIGS. 4-6 . While the implantation instrument  40  is held in place maintaining the temporary reshaping of the valve annulus  20 , the annuloplasty implant  50  may be inserted to the mitral valve by means of conventional techniques for inserting an annuloplasty ring using a carrier. The annuloplasty implant  50  is then sutured to the valve annulus in order to permanently keep the valve annulus  20  in its reshaped form. Thereafter, the carrier used for inserting the annuloplasty implant  50  and the implantation instrument  40  may be withdrawn leaving the annuloplasty implant  50  in the patient.  
         [0039]     It should be emphasized that the preferred embodiments described herein are in no way limiting and that many alternative embodiments are possible within the scope of protection defined by the appended claims.  
         [0040]     For example, the access to the heart valve may be achieved endoscopically. In such case, the implantation instrument  40  and the annuloplasty implant  50  need to be inserted through a narrow tube (endoscope). This implies that the implantation instrument  40  and the annuloplasty implant  50  will need to be compressed during insertion in order to pass through the endoscope. The implantation instrument  40  needs to assume its proper shape after having been passed through the endoscope. Therefore, using an endoscopic approach, the implantation instrument  40  should preferably be formed from a shape memory material. This allows the implantation instrument  40  to be compressed and also to have a stable shape when being applied to the heart valve. Further, the annuloplasty implant  50  needs to be flexible in order to be compressed for the insertion through the endoscope.