Patent Abstract:
An apparatus for the repair of a cardiovascular valve has leaflets comprising a grasper capable of grabbing and co-apting the leaflets of the valve. In a preferred embodiment the grasper has jaws that grasp and immobilize the leaflets, and then a fastener is inserted to co-apt the leaflets. The apparatus is particularly useful for repairing mitral valves to cure mitral regurgitation.

Full Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates generally to the field of circulatory valve repair. More particularly, the present invention relates to the field of the repair of heart valves and specifically for the repair of mitral heart valves, for patients suffering from mitral regurgitation.  
         BACKGROUND OF THE INVENTION  
         [0002]    There are four valves in the heart that serve to direct the flow of blood through the two sides of the heart in a forward direction. On the left side, the mitral and aortic valves direct oxygenated blood coming from the lungs, through the left side of the heart, into the aorta for distribution to the body. On the right side, the tricuspid valve, located between the right atrium and the right ventricle, and the pulmonary valve, located between the right ventricle and the pulmonary artery, direct de-oxygenated blood coming from the body, through the right side of the heart, into the pulmonary artery for distribution to the lungs. The anatomy of the heart and the structure and terminology of heart valves are described and illustrated in detail in numerous reference works on anatomy and cardiac surgery, including standard texts such as  Surgery of the Chest  (Sabiston and Spencer, eds., Saunders Publ., Philadelphia) and  Cardiac Surgery  by Kirklin and Barrett-Boyes, Pathology and Abnormalities of Heart Valves, incorporated herein by reference.  
           [0003]    All four heart valves are passive structures in that they do not themselves expend any energy and do not perform any active contractile function. They consist of moveable “leaflets” that are designed simply to open and close in response to differential pressures on either side of the valve. The mitral valve has two leaflets and the triscupid valve has three. The aortic and pulmonary valves are referred to as “semilunar valves” because of the unique appearance of their leaflets, which are most aptly termed “cusps” and are shaped somewhat like a half-moon. The components of the mitral valve assembly include the mitral valve annulus; the anterior leaflet; the posterior leaflet; two papillary muscles which are attached at their bases to the interior surface of the left ventricular wall; and multiple chordae tendineae, which couple the mitral valve leaflets to the papillary muscles.  
           [0004]    The problems that can develop with valves can be classified into two categories: (1) stenosis, in which a valve does not open properly, or (2) insufficiency, or regurgitation, in which a valve does not close properly.  
           [0005]    Mitral regurgitation (“MR”) is caused by dysfunction of the mitral subvalvular apparatus or direct injury to the valve leaflets. Multiple etiologies can lead to mitral regurgitation, with myxomatous degeneration of the valve and ischemic heart disease accounting for close to 60% of cases. Repair of the diseased valve requires major surgery on cardiopulmonary bypass to allow access to the valve. Consequently, some patients in the early or late stages of the disease are not considered appropriate candidates due to the high risk associated with the operation. Multiple studies have demonstrated that prosthetic replacement of the mitral valve can lead to significant postoperative left ventricular dysfunction and often requires lifelong treatment with anticoagulants. Mitral valve repair, using a posterior annuloplasty ring, has demonstrated improved results with better ventricular recovery. Nevertheless, recent studies performed by the inventors (Umana et al., Surg Forum 1997) have revealed that posterior ring annuloplasty causes changes in ventricular geometry that lead to paradoxical movement of the normal papillary muscles, further deteriorating ventricular performance. In contrast, the “bow-tie” repair in which the anterior and posterior leaflets of the mitral valve are fixed in opposition appears to enhance annular contractility while preserving ventricular architecture. This has resulted in improved postoperative ventricular function almost uniformly.  
           [0006]    The present invention addresses the needs of all patients with mitral regurgitation without mitral stenosis, including those who heretofore may have been excluded due to having only moderate MR or being too sick to be candidates for major surgery.  
           [0007]    The present invention finds utility not only for the repair of mitral valves but for all valves of the circulatory system, including aortic valves, tricuspid valves, and venous valves.  
           [0008]    Techniques for improving the efficacy of corporeal valves are known. For example, Laufer et al., U.S. Pat. No. 5,609,598 describes a valving system for treatment of chronic venous insufficiency. The system has inherent limitations in terms of its effectiveness for the procedure described and its applicability, if any, to other valves, especially cardiac valves.  
         SUMMARY OF THE INVENTION  
         [0009]    The present invention is directed to a method and apparatus for use in heart valve repair involving the use of an inserted device or grasper for grabbing and clasping together the anterior and posterior leaflets of the valve, by insertion into the left ventricle through the right chest via a thorascope, through the jugular vein, or through the femoral artery. The grasper will grab both leaflets, preferably after the heart has been stopped or slowed pharmacologically. The correctness of the initial grasp is assessed by, for example, intraoperative echocardiography, to ensure, for example, in the case of the mitral valve, that the mitral regurgitation is resolved. If not, the grasper will be able to “adjust” the leaflets to allow better coaptation or, if needed, re-grab the leaflets in a different location.  
           [0010]    Either inherent to the grasper, as an integrally attached component or as a separate device, a fastening device is introduced and a fastener is deployed to securely hold the leaflets in place after the grasper has been released. The remaining portion of the device, or optionally any separate device, is then removed.  
           [0011]    Accessory devices needed for the procedure include instruments for thoracoscopic or percutaneous approaches. While the preferred method and apparatus described hereinbelow is discussed with reference to its use in connection with mitral valve repair, it is contemplated that the same or substantially similar apparatus and methodology would also be useful in repairing other valves found in the human circulatory systems, particularly other heart valves, such as, for example, venous valves, aortic valves and tricuspid valves, amongst others.  
         OBJECTS OF THE INVENTION  
         [0012]    It is an object of the invention to provide a method for the repair of heart valves to increase their efficiency.  
           [0013]    It is a further object of the invention to provide for a method for the repair of mitral valves to reduce mitral regurgitation.  
           [0014]    It is also an object of the invention to provide for a method for the repair of the mitral valves which eliminates the need for cardiopulmonary bypass surgery.  
           [0015]    It is a further object of the invention to provide for an apparatus for percutaneous insertion into the heart to effect the repair of a heart valve.  
           [0016]    It is a yet further object of the invention to provide for the repair of a mitral valve by percutaneous insertion of a grasping and fastening device into the heart to repair a mitral valve and reduce or eliminate mitral regurgitation.  
           [0017]    These and other objects of the invention will become apparent to one skilled in the art from the more detailed description given below. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0018]    FIGS.  1  to  4  are each a schematic representation of a portion of the human heart showing the mitral valve, the left ventricle and an apparatus of the invention in operation;  
         [0019]    [0019]FIG. 5 is a schematic representation of an embodiment of the distal portion of an apparatus of the invention useful for grasping a mitral valve;  
         [0020]    [0020]FIG. 6 is a schematic representation of an embodiment of a distal portion of an apparatus of the invention showing a configuration of a fastener holder and a fastener clip in the open position;  
         [0021]    [0021]FIG. 7 is a schematic representation of an embodiment of FIG. 6 showing the release and closure of the fastener clip;  
         [0022]    [0022]FIG. 8 is a detailed, partly cross-sectional schematic representation of the distal end of a preferred embodiment of a grasper device according to the invention in the open position;  
         [0023]    [0023]FIG. 9 is a detailed, partly cross-sectional schematic representation of the preferred embodiment of a grasper device according to the invention shown in FIG. 8 in a closed position depicting the translocated adjustable grasper and fastener anvil within the jaws;  
         [0024]    [0024]FIG. 10 is a cross-sectional representation across line  10  - 10  of the adjustable grasper shown in FIG. 9;  
         [0025]    [0025]FIG. 11 is a detailed schematic representation of a preferred embodiment of the grasper device of the apparatus of the invention in the closed position with the integral closure means shown;  
         [0026]    [0026]FIG. 12 is a detailed schematic representation of the preferred embodiment depicted in FIG. 9 showing the closure means piercing the leaflets of the valve;  
         [0027]    [0027]FIG. 13 is a detailed, partly cross-sectional schematic representation of yet another preferred embodiment of the distal end of a grasper device according to the invention showing the use of a coil closure means;  
         [0028]    [0028]FIGS. 14, 15, and  16  are partly cross-sectional schematic representations of another embodiment of the invention, wherein a self-closing closure is used;  
         [0029]    [0029]FIG. 17 is a schematic representation of the self-sealing closure;  
         [0030]    [0030]FIGS. 18 and 19 are schematic representations of an embodiment of the invention with a three-piece closure;  
         [0031]    [0031]FIG. 20 is a schematic representation of an embodiment of the invention with a three-piece closure;  
         [0032]    [0032]FIGS. 21 and 22 are oblique, schematic representations of a valve leaflet closure useful according to the invention;  
         [0033]    [0033]FIG. 23 is a partial cross-sectional view of the closure shown in FIGS. 21 and 22;  
         [0034]    [0034]FIG. 24 is an oblique, schematic representation of another valve leaflet closure useful according to the invention;  
         [0035]    [0035]FIG. 25 is a partial cross-sectional view of the closure in FIG. 24 in position;  
         [0036]    FIGS.  26  to  28  are each an oblique, schematic representation of a spiral coil valve leaflet closure useful according to the invention;  
         [0037]    [0037]FIG. 29 is an oblique schematic representation of a U-shaped valve leaflet closure useful according to the invention; and  
         [0038]    [0038]FIG. 30 is a partly cross-sectional view of the closure shown in FIG. 29. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0039]    The invention can perhaps be better appreciated by making reference to the drawings. In FIG. 1 a portion of the human heart is depicted showing a mitral valve  10 , a left ventricle  12  and the distal end  14  of a grasper apparatus of  20  the invention  16 , which has been inserted through an incision  18  in left ventricle  12 . Incision  18  is loosely sutured with sutures  20  to loosely hold distal end  18  and to prevent bleeding.  
         [0040]    Mitral valve  10  comprises anterior leaflet or cusp  22  and posterior leaflet or cusp  24 , as well as two commissural cusps (not shown). The primary intent of the invention herein is to secure the distal sections  26  and  28  of cusps  22  and  24 , respectively, together or substantially adjacent.  
         [0041]    As can be seen in FIG. 2, the jaws  30  of distal end  14  are separated and positioned exterior to cusps  22  and  24 . Then, as shown in FIG. 3, jaws  30  are clamped together to cause cusp distal sections  26  and  28  to come together. Once a closure is embedded, such as the loop closure  32  in FIG. 4, jaws  30  are opened slightly so that distal section  14  can be withdrawn.  
         [0042]    The distal ends of the grasper means can vary greatly. It is contemplated that a variety of grasper means may be employed having differing grasper configurations and elements. For example, it is contemplated that the grasper means could be of the type wherein one side of the grasper is stationary and the other side movable. Alternatively, the grasper means might be of the type wherein both sides are movable in concert. Another alternative arrangement comprises a grasper means having multiple grasper elements to enable one to grasp and hold the leaflets of the valve in multiple locations. It is also contemplated that the grasper elements themselves might comprise one or more suction elements to secure and hold the valve leaflets in place. Preferably the grasper will have the capacity to adjust the leaflets of, for example, a mitral valve to obtain optimal coaptation.  
         [0043]    In addition it is contemplated that the grasper may comprise additional technology to facilitate the operation of the grasper. For example, the grasper may have echo doppler probe or a similar visualization technology that would allow even better localization of the leaflets and confirmation of ideal coaptation.  
         [0044]    [0044]FIG. 5 depicts the grasper end  36  of a percutaneous apparatus  38  with jaws  40  in the open position. Jaws  40  of grasper end  36  are movably engaged about joint  42  such that the jaws may be easily and freely opened or closed by the operator of the percutaneous apparatus.  
         [0045]    Depicted in FIG. 6 is an embodiment of the invention showing one possible configuration of a fastener holder  44  with a fastener clip  46  in place held in the open position for placement over the grasped leaflets of a mitral valve. The fastener holder  44  and fastener clip  46  may be integral with a grasper end as shown in FIG. 5 or separate from it, in which case it will be necessary to also provide a secondary percutaneous means for use in delivering and manipulating the fastener holder  44  and releasing and fixing the fastener clip  46  in the proper position about the leaves of a mitral valve, once they have been properly grasped by jaws  40  of grasper end  36 .  
         [0046]    [0046]FIG. 7 is a more detailed schematic representation of the fastener holder  44  with its jaws  48  in their open position and fastener clip  46  in place in the open position (dotted line). Also shown is fastener clip  46  in its released, closed position. Fastener clip  46 , which may have a closed diameter of from about 3 to 7 mm, preferably about 5 mm, will be comprised of a suitable material such as stainless steel, nitinol, or titanium.  
         [0047]    [0047]FIG. 8 depicts a detailed, partly cross-sectional schematic representation of a preferred embodiment of the grasper device of the present invention, comprising grasper end  50 , movable jaws  52  which are movably engaged about joint  54 , in the open position, in proximity to valve leaflets  56 . Each jaw  52  has a protruding grasping surface  58 . However, the grasping surface  58  of one jaw  52  is operatively and slidably connected to a control member  60  to enable one to properly align valve leaflets  56 , prior to fastening.  
         [0048]    In FIG. 9 the grasper device of the apparatus of the invention shown in FIG. 8 is in a closed position. Moveable jaws  52  have protruding grasper surfaces  58 , which engage valve leaflets  56 . Leaflets  56  are translocated to a more optimum position for fastening by the action of control member  60  on one of protruding grasping surfaces  58 , as shown in FIG. 11. Also, stapler action rod  68  is now operatively connected to stapler control member  70 .  
         [0049]    [0049]FIG. 10 is a schematic representation of a cross section of the adjustable grasper depicted in FIG. 9. The jaws comprise grasper surfaces  58 , an upper anvil  62  with recess  71 , and a lower anvil  64  within which is located a staple type fastener  66  to effect the fastening of valve leaflets.  
         [0050]    As shown in FIGS. 9, 11, and  12 , lower anvil  64  has at least one slanted surface member  72 . When stapler action rod  68  is forced distally against slanted surface member  72 , stapler fastener  66  is forced through leaflets  56  into upper anvil  62  to close stapler fastener  66 .  
         [0051]    In another embodiment of the invention shown in FIG. 13, a grasper  80  comprises jaws  82 , 84 . Jaw  82  is movably connected to rod  86  at pivot point  87 , and jaw  84  is movably connected at pivot point  88  to rod  90 . Rod  92  is movably connected to jaw  84  at pivot  94 . Operation of rods  90  and  92  causes jaws  82  and  84  to open and close on valve leaflets  96 . Axial to grasper  80  is a sheath  98  containing a drive mechanism  100  for rotating coil fastener  102 . Coil fastener  102  advances in a spiral mode piercing leaflets  96  in multiple locations as coil  102  is advanced into its final position.  
         [0052]    Rods  86 ,  90 , and  92  are each operatively connected to one or more control mechanisms (not shown). Also, distal section jaws  82 , 84  may be slidable within grasper sheath  81 .  
         [0053]    Another device  110  of the invention is shown in FIGS.  14  to  16 , where jaws  112  are operatively connected to a handle mechanism (not shown). Device  110  comprises a movable sheath  114  that contains a straightened closure fastener  116  that is capable of resuming or forming a circular shape to coapt valve leaflets (not shown). Device  110  has a slidably extruding grasping surface  118  that is operatively connected to the handle mechanism.  
         [0054]    Once jaws  112  are closed, the distal tip of sheath  114  is advanced distally to be adjacent grasping surface  118  and its cooperating grasping surface  122 . A pusher  124  coerces fastener  116  to advance out of the distal end  126  of sheath  114  to form a circular shape. Fastener  116  in this shape will coapt valve leaflets  120 , as can be seen in FIG. 17.  
         [0055]    The device  130  of the invention shown in FIGS. 18 and 19 is intended to form a three-piece closure device. Jaws  132  each removably hold a closure member  134  having a grasping surface  136 . Located axially with device  130  is a closure crimper  138  that is removably fastened at the distal end  140  of a device rod  142 . When jaws  132  grasp valve leaflets  144 , closure crimper  138  is advanced distally by device rod  142  to fit over the proximal ends of closure members  134 . The closure formed is shown in FIG. 20.  
         [0056]    While a typical grasper means configuration would normally require the use of at least one control wire to actuate the grasper element(s), it is contemplated that multiple separate control wires could also be effectively employed and manipulated from the proximal end of the system to allow for the precise control of the individual grasper elements.  
         [0057]    With regard to the fastening means employed, as noted above it is contemplated that the fastening means may be constituted as a single apparatus operating in concert with the grasper means. Alternatively, the fastening means may be constituted as an entirely separate device which is totally independent of the grasper means. More preferably the fastening means will be a separate device which will function using a monorail type system, wherein the fastening means will operate independently of the grasper means, but will ride via a loop over the same guidewire/catheter which houses and guides the grasper means.  
         [0058]    While the preferred fastener depicted is in the form of a clip or staple, it is also contemplated that the fasteners employed to secure the leaflets of the valve may be of a variety of different configurations, each of which would function with greater or lesser effectiveness depending upon the operative conditions which prevail. In addition to clips or staples it is also contemplated that the following types of fasteners may also be effectively employed: coils, sutures, dual button fasteners, cufflink-like fasteners, and the like.  
         [0059]    Suitable suture fasteners would include those which might require an appropriate mechanism to automatically suture tissue. Coil fasteners would generally be provided with sharpened ends to allow one to screw these fasteners into place by threading the sharpened end through the tissue of the valve leaflet.  
         [0060]    With reference to FIGS.  21  to  23  which depict a sequential representation of the closure of valve leaflets using one preferred closure means, shown in FIG. 22 is a clip type closure  150  being inserted through valve leaflets  152 . FIG. 22 shows the clip type closure  150  in the fastened position. FIG. 23 is a cross-sectional view of the clip type closure 150 depicted in FIG. 23. Each closure  150  as shown in FIG. 21 would have a thickness of from about 0.5 to 1.8 mm, preferably about 1 mm, a width of from about 0.3 to 0.7 cm, preferably about 0.5 cm, and a length of from about 0.6 to 1.4 cm, preferably about 1 cm.  
         [0061]    [0061]FIGS. 24 and 25 are each a schematic representation of the insertion of another preferred closure means of the invention. A staple-type closure  156  is inserted through valve leaflets  158 , and then closed, as shown in FIG. 26. Closure  156  would preferably have an overall length (including sides) of from about 1 to 4 cm, preferably about 3 cm, an effective diameter of from about 0.1 to 0.5 mm, preferably about 0.3 mm, and an opening of from about 0.5 to 1.3 cm, preferably about 1 cm.  
         [0062]    FIGS.  26  to  28  are each a schematic representation of the insertion of yet another preferred closure. A spiral coil closure  160  can be inserted across valve leaflets  162  in longitudinal, latitudinal, or transverse fashion, by use of, for example, the device shown in FIG. 13. Coils  160  will preferably have pointed ends and will have external dimensions comprising a length of from about 3 to 7 cm, preferably about 5 cm, and a diameter of from about 1 to 3 mm, preferably about 2 mm.  
         [0063]    The overall diameter and/or the differential turns of coil  160  may be uniform or they may vary. For example, the diameter at each end of coil  160  could be the same as, greater than, or less than the diameter of the middle portion of the coil. Similarly, the ratio of the turns of the coil to the length, i.e., the pitch, could be consistent or the pitch could be greater or less at each end of the coil. The diameter of the coil wire will preferably be consistent.  
         [0064]    Each coil  160  would have a length of from about 3 to 7 cm, preferably about 5 cm, with a diameter of from about 1 to 3 mm, preferably about 2 mm, and a coil wire diameter of from about 0.2 to 0.4 mm. The winding of coil 160 should be from about 5 to 10 turns/cm in an unstressed condition.  
         [0065]    In FIGS. 29 and 30 a U-shaped barbed clip-type closure  164  is applied to leaflet  166 .  
         [0066]    The device and fasteners used according to the invention must be comprised of biocompatible, nonimmunogenic materials. The grasper is preferably comprised of rigid materials such as titanium, nitinol, stainless steel, or rigid polymeric material such as polyethylene or polyurethane. The clips, staples, coils, etc., are preferably comprised of titanium, nitinol, or stainless steel. In some instances fasteners comprised of molded polymeric material may also be useful.  
         [0067]    There are four different approaches which one might take to effect a repair of the mitral heart valve according to the invention:  
         [0068]    Such a procedure might be undertaken while the patient is on by-pass with an open-chest, either transapically or transatrially. A median sternotomy is performed and the patient is placed on cardiopulmonary bypass by cannulating the ascending aorta and the right atrium. A purse-string suture is then placed on the apex of the left ventricle and a stab incision performed to insert the instrument which will grasp and attach the mitral valve leaflets. Once adequate repair of the valve is attained, the instrument is removed and the air evacuated from the left ventricle through the apical incision. The ventricle is then repaired using conventional wound closure techniques.  
         [0069]    Alternatively, the grasper can be introduced through a similar stab incision performed over the roof of the left atrium. The grasper will cross the valve and then be manipulated to revert to grasp the leaflets from the atrial side and place the suturing device, just as postulated from the transventricular approach. Once adequacy of repair is confirmed, the device is extracted and the atriotomy closed using conventional wound closure techniques.  
         [0070]    This procedure can alternatively be performed with the patient off bypass, through either a left or right thoracotomy or a sternotomy incision. The technique would be similar to that outlined for repair of mitral regurgitation on cardiopulmonary bypass. After opening the chest, the patient is placed on medication (beta-blocker) to slow the heart rate to approximately 40 beats per minute. This allows adequate echocardiographic visualization of the leaflets in order to grasp and attach them.  
         [0071]    Third, such a procedure can be undertaken thorascopically. The patient is intubated selectively in order to collapse the left lung, and percutaneous ports are inserted in to the left chest allowing visualization of the apex of the heart or left atrium. Through a separate port, the device is introduced into the thoracic cavity and subsequently into the left ventricle through the apex. Previously, a purse-string or triangular suture had been placed around the tip of the ventricle to control bleeding around the ventricular entry site. Subsequent steps of the repair are identical to those described for patients with an open chest, off bypass.  
         [0072]    Should the operation require the patient to be placed on bypass, this can be attained percutaneously from the groin by cannulating the femoral artery and vein. This technique could prove particularly useful in the early stages of development of the technique, since the surgeon would be able to operate on a decompressed heart and slow or cease the heart rate as needed, without hemodynamic compromise.  
         [0073]    Lastly, a percutaneous approach to repair of the mitral valve would be possible with this invention by inserting the device either through the femoral artery or jugular vein. When using the former, the left ventricle is reached by placing the device across the aortic valve. The leaflets will be grasped by turning the tip of the instrument approximately 160° from the entry angle. As previously stated, the grasper&#39;s tips are adjusted to obtain optimal apposition and the suturing device delivered. If a transvenous approach is employed, the left atrium is entered through the interatrial septum and the leaflets are handled as described for the transatrial technique.  
         [0074]    To determine the relative efficacy of the method of the invention in effecting the repair of heart valves such as mitral valves a number of procedures were performed on both animal and human test subjects as follows:  
         [0075]    Animal Testing  
         [0076]    Six adult sheep underwent ligation of OM2 and OM3 through a left thoracotomy to induce chronic ischemic MR. After 8 weeks, animals were placed on cardiopulmonary bypass. Using a posterior approach to the left atrium, a bow-tie repair was performed. A posterior suture annuloplasty (DeVega) served as control. Snares were placed on both repairs to allow alternate tightening during measurements. Ten 2-mm piezo-electric crystals were sutured around the MV annulus and at the bases and tips of the papillary muscles. Six crystals were secured to the apex ( 1 ), septum ( 1 ), and epicardial short axis of the left ventricle ( 4 ) for 3-dimensional sonomicrometry array localization (3D-SAL) imaging. 3D-SAL measurements were performed after weaning from cardiopulmonary bypass at baseline and with each type of repair. Echocardiography was used to measure MR, MV area, and fractional shortening.  
                                                       TABLE 1                           MR, mitral valve area, and fractional shortening                MR   FS   MVA (cm 2 )                            Baseline   3.3   0.46   5.4           DeVega   1.4   0.53   31.9           Bow-tie   1.2   0.57   3.3                                                          
 
         [0077]    As shown from the results presented in Table 1, MR decreased significantly with both repairs compared with baseline. Post-operative improvements in fractional shortening was greater in the bow-tie group but did not reach statistical significance. MVA, measured by planimetry, decreased more with the bow-tie repair; nevertheless, the resultant areas were still substantial without evidence of a transvalvular gradient. Mitral valve annular contractility (% area change=(maximum area−minimum area)/maximum area) by 3D-SAL increased from 19.7%±4.0% at baseline to 21.5%±3.2% after bow-tie repair (P=0.026). Suture annuloplasty decreased annular contractility to 15.7%±3.6% (P=0.0011 vs. baseline, and P=0.0001 vs. bow-tie).  
         [0078]    The results obtained suggest that current techniques of mitral valve repair in ischemic MR may further impair left ventricular performance by limiting systolic function of the annulus and base of the heart. The bow-tie repair technique which is the subject of the present invention controls MR and directly addresses subvalvular dysfunction resulting in improved annular and left ventricular function.  
         [0079]    Human Testing  
         [0080]    The charts of eleven patients (five males and six females) undergoing mitral valve repair in conjunction with a central leaflet suture (“bow-tie” repair) were reviewed. Patients were operated on between August1996 and April 1997. Mean age was 68 years (range, 44 to 78). Etiology of mitral regurgitation (MR) was ischemic in nine patients and degenerative in two. Mitral regurgitation was attributed to ischemia if any of the following criteria proposed by Radford et al. was met: (1) rupture of a papillary muscle chord or head (n=3); (2) infarction of the papillary muscle in the absence of leaflet pathology (n=3); (3) clear history of new onset or worsening of mitral regurgitation after documented myocardial infarction (n=3).  
         [0081]    The diagnosis of MR was established by echocardiography in 10/10 patients, and semiquantitatively graded as severe (4+), moderate/severe (3+), mild/moderate (2+), mild (1+), and trace. Left sided cardiac catheterization confirmed the presence of MR in nine patients and the presence of critical coronary artery disease (CAD) invariably involving the circumflex and posterior descending artery territories in all patients with ischemic MR. Preoperative diagnoses and hemodynamics obtained during catheterization are shown in Table 2. All patients were in NYHA class III or IV at the time of surgery.  
                                                                   TABLE 2                           Preoperative diagnosis and hemodynamics.            Patient   Diagnosis   Age   CO   PCWP   v-wave                    1   Unstable angina   59   4.2   30   80       2   CAD/torn post. chord   78   2.4   6   10       3   CAD   74   n/a   14   15       4   CAD/MIx3   64   n/a   n/a   n/a       5   Unstable angina/MIx2   44   4.0   26   41       6   Ischemic VSD   77   4.0   28   21       7   AI/MR   77   4.5   29   39       8   CAD/APM rupture   67   4.3   27   65       9   CAD/V-tach arrest   71   4.1   20   28       10   Degenerative MR   70   3.5   20   21       11   AMI/PPM rupture   67   4.1   33   60                  
 
         [0082]    AI-aortic insufficiency; AMI-acute myocardial infarction; APM-anterior papillary muscle; CAD-coronary artery disease; post-posterior; PPM-posterior papillary muscle; VSD-ventricular septal defect; v-tach-ventricular tachycardia  
         [0083]    With the patient under anesthesia, the valve is visualized on transesophageal echocardiogram (TEE) and the likely mode of failure determined, with special emphasis on the presence of leaflet prolapse and site and direction of the regurgitant jet. After the heart was stopped, a bulb syringe with cold saline is used to distend the left ventricle and confirm the mode of valve failure. A conventional repair using an annuloplasty right is generally performed and the valve is reinspected with saline injection. If the leaflet edges do not oppose each other in a concentric circle parallel to the annuloplasty ring, and continued regurgitation is observed, then a “bow-tie ” repair is iniatiated. If the repair is performed from the tranventricular or transaortic exposure, a single figure of eight 4-0 prolene suture is placed without screening leaflet eight 4-0 prolene suture is placed without screening leaflet coaptation. Using a 4-0 prolene suture, the anterior leaflet is attached to the corresponding posterior leaflet at the site of malapposition. The figure of 8 suture is placed through each leaflet just as the edge turns down to attach to the primary chordae. This is usually the most cephalad site where the 2 leaflets would touch during systole and creates the largest area of coaptation possible.  
         [0084]    At time the suture is very close to a commissure and the result is a narrowing of single valve orifice. More commonly, the suture is closer to the center of the valve and a double orifice valve is created which resembles a “bow-tie”. After visually confirming that the repair is satisfactory with cold saline injection, the atrium is closed, the patient weaned from CPB, and an intraoperative TEE used to confirm the adequacy of the repair. Standard as well as exercise transthoracic echocardiograms were performed prior to discharge to establish the competency of the “bow-tie” repair as well as the absence of a significant gradient across the valve.  
         [0085]    Six patients were operated on electively for worsening MR leading to intractable congestive heart failure or unstable angina. Four patients underwent emergent operation due to acute worsening of MR secondary to ischemic anterior papillary muscle rupture (n=2), acute MI with cardiogenic shock requiring intraaortic counterpulsation balloon, severe MR and malignant arrhythmias (N=1 ), and acute worsening of chronic degenerative MR (n=1 ). One patient had moderate (3+0) MR in association with critical aortic insufficiency. Mean degree of preoperative MR by echo was 3.5±0.7, with mean ejection fraction (EF) of 42%±17%. Nine patients underwent preoperative cardiac catheterization. Mean pulmonary capillary wedge pressure was 23 mmHg±8 mmHg, with mean atrial v-wave of 39 mmHg±25 mmHg; mean CO as measured by thermodilution technique was 3.9 1/min (range 2.4 to 4.5 1/min) (Table 2). Concomitant procedures performed at the time of MR included coronary artery bypass grafting (CABG) in eight patients. Of the two patients with a degenerative etiology of valvular disease, one required aortic valve replacement, whereas the second underwent posterior leaflet quadrangular resection and annuloplasty. Two patients, not included in this series, with end-stage congestive heart failure (CHF) secondary to ventricular dilation had “bow-tie” repairs during partial left ventriculectomy. Nine patients had a posterior ring annuloplasty as primary procedure for treatment of MR (Table 3). One patient required repair of ischemic ventricular septal defect (VSD) through a ventriculotomy, which made insertion of an annuloplasty ring impractical. This patient&#39;s mitral valve was successfully repaired with a “bow-tie” alone. A second patient presented with acute MR secondary to rupture of the anterior head of the ppm. Repair of the papillary muscle was performed using pericardial pledgets. Due to the lack of annular dilatation and persistence of MR a “bow-tie” suture was placed without an annuloplasty ring. Control of MR assessed intraoperatively by direct cold saline injection and TEE was satisfactory in all patients.  
                                           TABLE 3                           Operative indications and concomitant procedures            Patient   Operative indication   Other procedures                    1   MR. unstable angina   CABG, C-E#28       2   Torn post chord, MR   Post quad resection, C-E               #32       3   CAD, MR   CABG, C-E#32       4   CAD, MR   CABG, C-E#30       5   Unstable angina, MR   CABG, C-E#28       6   Ischemic VSD, MR   CABG       7   Critical AI, MR   AVR, C-E#30       8   CAD, ALM rupture, MR   CABG, C-E#26       9   CAD, MR   CABG, C-E#28       10   MR, CHF   C-E#30       11   PPM rupture, MR   CABG, primary PPM repair                          
 
         [0086]    It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the constructions set forth without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.  
         [0087]    It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.  
                                                   DRAWING COMPONENTS            No.   Component                    10   mitral valve       12   left ventricle       14   distal end of grasper       16   grasper       18   incision       20   suture       22   anterior leaflet or cusp       24   posterior leaflet or cusp       26   anterior cusp distal section       28   posterior cusp distal section       30   jaw       32   closure loop       36   grasper end       38   percutaneous apparatus       40   jaw       42   joint       44   fastener holder       46   fastener clip       48   jaw       50   grasper end       52   jaw       54   joint       56   valve leaflet       58   protruding grasping surface       60   control number       62   upper anvil       64   lower anvil       66   staple type fastener       68   staple action rod       71   recess       72   anvil slanted surface       80   grasper       81   grasper sheath       82   jaw       84   jaw       86   rod       87   pivot point       88   pivot point       90   rod       92   rod       94   pivot       96   valve leaflet       98   sheath       100   drive mechanism       102   coil fastener       110   grasper device       112   jaw       114   sheath       116   fastener       118   grasping surface       120   leaflet       122   cooperating grasping surface       124   pusher       130   grasper device       132   jaw       134   closure member       136   grasping surface       138   closure crimper       140   rod distal end       142   device rod       144   valve leaflet       150   clip-type closure       152   valve leaflet       156   staple-type closure       158   valve leaflet       160   spiral closure       162   valve leaflet       164   barbed-clip closure       166   valve leaflet

Technology Classification (CPC): 0