Abstract:
Methods and devices for repairing a cardiac valve. A minimally invasive procedure includes creating an access in the apex region of the heart through which one or more instruments may be inserted. The device can implant artificial heart valve chordae tendineae into cardiac valve leaflet tissues to restore proper leaflet function and prevent reperfusion. The device punctures the apex of the heart and travels through the ventricle. The tip of the device rests on the defective valve and punctures the valve leaflet. A suture or a suture/guide wire combination is inserted, securing the top of the leaflet to the apex of the heart. A resilient element or shock absorber mechanism adjacent to the outside of the apex of the heart minimizes the linear travel of the device in response to the beating of the heart or opening/closing of the valve.

Description:
RELATED APPLICATIONS 
       [0001]    This application is a divisional of and claims priority to U.S. patent application Ser. No. 14/138,857, filed Dec. 23, 2013, entitled “Transapical Mitral Valve Repair Device,” which is a continuation of and claims priority to International Application No. PCT/US2012/043761, filed Jun. 22, 2012, entitled “Transapical Mitral Valve Repair Device,” which claims priority to and the benefit of U.S. Provisional Application No. 61/501,404, filed Jun. 27, 2011, entitled “Transapical Mitral Repair with Pre-Formed Knot,” and U.S. Provisional Application No. 61/550,772, filed Oct. 24, 2011, entitled “Transapical Mitral Valve Repair Device,” the disclosures of which are incorporated herein by reference in their entirety. 
     
    
     BACKGROUND 
       [0002]    1. Field of the Disclosure 
         [0003]    The disclosure herein relates to methods and devices for performing cardiac valve repairs, and more particularly, the disclosure relates to methods and devices for performing minimally invasive mitral or tricuspid valve repairs using of PTFE neochords through a minimally invasive incision, while the heart is beating. 
         [0004]    2. Description of the Background 
         [0005]    As illustrated in  FIG. 1 , the human heart  10  has four chambers, which include two upper chambers denoted as atria  12 ,  16  and two lower chambers denoted as ventricles  14 ,  18 . A septum  20  divides the heart  10  and separates the left atrium  12  and left ventricle  14  from the right atrium  16  and right ventricle  18 . The heart further contains four valves  22 ,  24 ,  26 , and  28 . The valves function to maintain the pressure and unidirectional flow of blood through the body and to prevent blood from leaking back into a chamber from which it has been pumped. 
         [0006]    Two valves separate the atria  12 ,  16  from the ventricles  14 ,  18 , denoted as atrioventricular valves. The left atrioventricular valve, the mitral valve  22 , controls the passage of oxygenated blood from the left atrium  12  to the left ventricle  14 . A second valve, the aortic valve  24 , separates the left ventricle  14  from the aortic artery (aorta)  30 , which delivers oxygenated blood via the circulation to the entire body. The aortic valve  24  and mitral valve  22  are part of the “left” heart, which controls the flow of oxygen-rich blood from the lungs to the body. The right atrioventricular valve, the tricuspid valve  26 , controls passage of deoxygenated blood into the right ventricle  18 . A fourth valve, the pulmonary valve  28 , separates the right ventricle  18  from the pulmonary artery  32 . The right ventricle  18  pumps deoxygenated blood through the pulmonary artery  32  to the lungs wherein the blood is oxygenated and then delivered to the left atrium  12  via the pulmonary vein. Accordingly, the tricuspid valve  26  and pulmonic valve  28  are part of the “right” heart, which control the flow of oxygen-depleted blood from the body to the lungs. 
         [0007]    Both the left and right ventricles  14 ,  18  constitute “pumping” chambers. The aortic valve  24  and pulmonic valve  28  lie between a pumping chamber (ventricle) and a major artery and control the flow of blood out of the ventricles and into the circulation. The aortic valve  24  and pulmonic valve  28  have three cusps, or leaflets, that open and close and thereby function to prevent blood from leaking back into the ventricles after being ejected into the lungs or aorta  30  for circulation. 
         [0008]    Both the left and right atria  12 ,  16  are “receiving” chambers. The mitral valve  22  and tricuspid valve  26 , therefore, lie between a receiving chamber (atrium) and a ventricle so as to control the flow of blood from the atria to the ventricles and prevent blood from leaking back into the atrium during ejection into the ventricle. Both the mitral valve  22  and tricuspid valve  26  include two or more cusps, or leaflets (shown in  FIG. 2 ), that are encircled by a variably dense fibrous ring of tissues known as the annulus. The valves are anchored to the walls of the ventricles by chordae tendineae (chordae)  42 . The chordae tendineae  42  are cord-like tendons that connect the papillary muscles  44  to the leaflets (not shown) of the mitral valve  22  and tricuspid valve  26  of the heart  10 . The papillary muscles  44  are located at the base of the chordae  42  and are within the walls of the ventricles. They serve to limit the movements of the mitral valve  22  and tricuspid valve  26  and prevent them from being reverted. The papillary muscles  44  do not open or close the valves of the heart, which close passively in response to pressure gradients; rather, the papillary muscles  44  brace the valves against the high pressure needed to circulate the blood throughout the body. Together, the papillary muscles  44  and the chordae tendineae  42  are known as the subvalvular apparatus. The function of the subvalvular apparatus is to keep the valves from prolapsing into the atria when they close. 
         [0009]    As illustrated with reference to  FIG. 2 , the mitral valve  22  includes two leaflets, the anterior leaflet  52  and the posterior leaflet  54 , and a diaphanous incomplete ring around the valve, called the annulus  60 . The mitral valve  22  has two papillary muscles  44 , the anteromedial and the posterolateral papillary muscles, which attach the leaflets  52 ,  54  to the walls of the left ventricle  14  via the chordae tendineae  42 . The tricuspid valve  26  typically is made up of three leaflets with three papillary muscles. However, the number of leaflets can range between two and four. The three leaflets of the tricuspid valve  26  are referred to as the anterior, posterior, and septal leaflets. Although both the aortic and pulmonary valves each have three leaflets (or cusps), they do not have chordae tendineae. 
         [0010]    Various disease processes can impair the proper functioning of one or more of the valves of the heart. These disease processes include degenerative processes (e.g., Barlow&#39;s Disease, fibroelastic deficiency), inflammatory processes (e.g., Rheumatic Heart Disease), and infectious processes (e.g., endocarditis). Additionally, damage to the ventricle from prior heart attacks (i.e., myocardial infarction secondary to coronary artery disease) or other heart diseases (e.g., cardiomyopathy) can distort the valve&#39;s geometry causing it to dysfunction. However, the vast majority of patients undergoing valve surgery, such as mitral valve surgery, suffer from a degenerative disease that causes a malfunction in a leaflet of the valve, which results in prolapse and regurgitation. 
         [0011]    Generally, a heart valve may malfunction two different ways. One possible malfunction, valve stenosis, occurs when a valve does not open completely and thereby causes an obstruction of blood flow. Typically, stenosis results from buildup of calcified material on the leaflets of the valves causing them to thicken and thereby impairing their ability to fully open and permit adequate forward blood flow. 
         [0012]    Another possible malfunction, valve regurgitation, occurs when the leaflets of the valve do not close completely thereby causing blood to leak back into the prior chamber. There are three mechanisms by which a valve becomes regurgitant or incompetent; they include Carpentier&#39;s type I, type II and type III malfunctions. A Carpentier type I malfunction involves the dilation of the annulus such that normally functioning leaflets are distracted from each other and fail to form a tight seal (i.e., do not coapt properly). Included in a type I mechanism malfunction are perforations of the valve leaflets, as in endocarditis. A Carpentier&#39;s type II malfunction involves prolapse of one or both leaflets above the plane of coaptation. This is the most common cause of mitral regurgitation, and is often caused by the stretching or rupturing of chordae tendineae normally connected to the leaflet. A Carpentier&#39;s type III malfunction involves restriction of the motion of one or more leaflets such that the leaflets are abnormally constrained below the level of the plane of the annulus. Leaflet restriction can be caused by rheumatic disease (Ma) or dilation of the ventricle (IIIb). 
         [0013]      FIG. 3  illustrates a prolapsed mitral valve  22 . As can be seen with reference to  FIG. 3 , prolapse occurs when a leaflet  52 ,  54  of the mitral valve  22  is displaced into the left atrium  12  during systole. Because one or more of the leaflets  52 ,  54  malfunction, the mitral valve  22  does not close properly, and, therefore, the leaflets fail to coapt. This failure to coapt causes a gap  63  between the leaflets  52 ,  54  that allows blood to flow back into the left atrium  12 , during systole, while it is being ejected into the left ventricle  14 . As set forth above, there are several different ways a leaflet may malfunction, which can thereby lead to regurgitation. 
         [0014]    Although stenosis or regurgitation can affect any valve, stenosis is predominantly found to affect either the aortic valve  24  or the pulmonic valve  28 , whereas regurgitation predominately affects either the mitral valve  22  or the tricuspid valve  26 . Both valve stenosis and valve regurgitation increase the workload on the heart  10  and may lead to very serious conditions if left un-treated; such as endocarditis, congestive heart failure, permanent heart damage, cardiac arrest, and ultimately death. Since the left heart is primarily responsible for circulating the flow of blood throughout the body, malfunction of the mitral valve  22  or tricuspid valve  26  is particularly problematic and often life threatening. Accordingly, because of the substantially higher pressures on the left side of the heart, left-sided valve dysfunction is much more problematic. 
         [0015]    Malfunctioning valves may either be repaired or replaced. Repair typically involves the preservation and correction of the patient&#39;s own valve. Replacement typically involves replacing the patient&#39;s malfunctioning valve with a biological or mechanical substitute. Typically, the aortic valve  24  and pulmonic valve  28  are more prone to stenosis. Because stenotic damage sustained by the leaflets is irreversible, the most conventional treatment for stenotic aortic and pulmonic valves is removal and replacement of the diseased valve. The mitral valve  22  and tricuspid valve  26 , on the other hand, are more prone to deformation. Deformation of the leaflets, as described above, prevents the valves from closing properly and allows for regurgitation or back flow from the ventricle into the atrium, which results in valvular insufficiency. Deformations in the structure or shape of the mitral valve  22  or tricuspid valve  26  are often repairable. 
         [0016]    Valve repair is preferable to valve replacement. Bioprosthetic valves have limited durability. Moreover, prosthetic valves rarely function as well as the patient&#39;s own valves. Additionally, there is an increased rate of survival and a decreased mortality rate and incidence of endocarditis for repair procedures. Further, because of the risk of thromboembolism, mechanical valves often require further maintenance, such as the lifelong treatment with blood thinners and anticoagulants. Therefore, an improperly functioning mitral valve  22  or tricuspid valve  26  is ideally repaired, rather than replaced. However, because of the complex and technical demands of the repair procedures, the overall repair rate in the United States is only around 50%. 
         [0017]    Conventional techniques for repairing a cardiac valve are labor-intensive, technically challenging, and require a great deal of hand-to-eye coordination. They are, therefore, very challenging to perform, and require a great deal of experience and extremely good judgment. For instance, the procedures for repairing regurgitating leaflets may require resection of the prolapsed segment and insertion of an annuplasty ring so as to reform the annulus of the valve. Additionally, leaflet sparing procedures for correcting regurgitation are just as labor-intensive and technically challenging, if not requiring an even greater level of hand-to-eye coordination. These procedures involve the implantation of sutures (e.g., ePTFE or GORE-TEXT™ sutures) so as to form artificial chordae in the valve. In these procedures, rather than performing a resection of the leaflets and/or implanting an annuplasty ring into the patient&#39;s valve, the prolapsed segment of the leaflet is re-suspended using artificial chord sutures. Oftentimes, leaflet resection, annuplasty, and neochord implantation procedures are performed in conjunction with one another. 
         [0018]    Regardless of whether a replacement or repair procedure is being performed, conventional approaches for replacing or repairing cardiac valves are typically invasive open-heart surgical procedures, such as sternotomy or thoracotomy, that require opening up of the thoracic cavity so as to gain access to the heart. Once the chest has been opened, the heart is bypassed and stopped. Cardiopulmonary bypass is typically established by inserting cannulae into the superior and inferior vena cavae (for venous drainage) and the ascending aorta (for arterial perfusion), and connecting the cannulae to a heart-lung machine, which functions to oxygenate the venous blood and pump it into the arterial circulation, thereby bypassing the heart. Once cardiopulmonary bypass has been achieved, cardiac standstill is established by clamping the aorta and delivering a “cardioplegia” solution into the aortic root and then into the coronary circulation, which stops the heart from beating. Once cardiac standstill has been achieved, the surgical procedure may be performed. These procedures, however, adversely affect almost all of the organ systems of the body and may lead to complications, such as strokes, myocardial “stunning” or damage, respiratory failure, kidney failure, bleeding, generalized inflammation, and death. The risk of these complications is directly related to the amount of time the heart is stopped (“cross-clamp time”) and the amount of time the subject is on the heart-lung machine (“pump time”). 
         [0019]    Furthermore, the conventional methods currently being practiced for the implantation of the artificial chordae are particularly problematic. Because the conventional approach requires the heart to be stopped (e.g., via atriotomy) it is difficult to accurately determine, assess, and secure the appropriate chordal length. Since the valve will not function properly if the length of the artificial chordae is too long or too short, the very problem sought to be eradicated by the chordal replacement procedure may, in fact, be exacerbated. Using conventional techniques, it is very difficult to ensure that the chordae are of the correct length and are appropriately spaced inside the ventricle to produce a competent valve. 
         [0020]    There is a significant need to perform mitral valve repairs using less invasive procedures while the heart is still beating. Accordingly, there is a continuing need for new procedures and devices for performing cardiac valve repairs, such as mitral and tricuspid valve repairs, which are less invasive, do not require cardiac arrest, and are less labor-intensive and technically challenging. Chordal replacement procedures and artificial chordae that ensure the appropriate chordal length and spacing so as to produce a competent valve are of particular interest. The methods and repair devices presented herein meet these needs. 
       SUMMARY 
       [0021]    It is an object of the disclosure to provide a method and device to enable minimally invasive, beating-heart, mitral valve repair. 
         [0022]    It is another object of the disclosure to provide an expansile element that can be inserted through a mitral valve leaflet, and which can be deployed above the valve leaflet in order to secure it in place. 
         [0023]    It is another object of the disclosure to enable chordal replacement with ePTFE. A related object of the present disclosure is to provide a chordal replacement that facilitates mitral valve repair. 
         [0024]    Another object of the disclosure is to provide a method and device for transapical mitral valve repair that uses a small incision. A related object of the disclosure is to provide a method that does not require a Sternotomy. Another related object of the disclosure is to provide a method that does not require cardiopulmonary bypass or aortic manipulation. 
         [0025]    Another object of the disclosure is to provide a method and device for transapical mitral valve repair that uses real-time, echo-guided, chordal length adjustment. 
         [0026]    A basic concept of the method of the disclosure herein is to insert a tool via the apex of the heart, grasp or pierce the defective heart valve leaflet, deploy a PTFE neochord, and adjust the length of the chord under echo guidance to resolve the mitral valve regurgitation. 
         [0027]    These and other objects of the present disclosure are accomplished by providing a device for minimally invasive repair of a defective heart valve while the heart is beating. The heart can be accessed through the apex or a point lateral/near to the apex with a small-diameter shafted instrument. The instrument might be a needle or a catheter. Using ultrasound guidance (real-time transesophagael echocardiography), the shafted instrument is inserted through an access port at the apex (or near the apex) and the instrument is guided to make contact with the mitral valve leaflet at the location where the operator has decided that a neochord should be inserted. Typically, this would be the body of the anterior or posterior leaflet in a location where the valve has prolapsed as a result of a broken or elongated chord. The instrument punctures the apex of the heart and travels through the ventricle. The tip of the instrument rests on the defective valve and punctures the valve leaflet. The instrument then inserts either a suture or a suture/guide wire combination, securing the top of the leaflet to the apex of the heart with an artificial chordae. A resilient element or shock absorber mechanism adjacent to the outside of the apex of the heart minimizes the linear travel of the instrument in response to the beating of the heart or opening/closing of the valve. 
         [0028]    In a first embodiment, the instrument punctures the defective leaflet twice. A first needle deploys a loop wire with the loop encircling the area immediately above a second needle. The second needle deploys a suture through the loop deployed by the first needle. After the loop ensnares the suture, the loop and suture are retracted into the first needle. The instrument is pulled out of the heart while the suture remains through the leaflet. The length of the suture is adjusted and the ends of the suture are then affixed to the outer surface of the heart near the apex of the heart. Typically, the suture would be secured to a pledget. 
         [0029]    According to another embodiment, once the instrument is in contact with the mitral valve leaflet in the targeted location, a “PTFE-wrapped needle” is advanced rapidly across the leaflet and subsequently rapidly withdrawn. After the PTFE-wrapped needle is advanced across the leaflet, the core is withdrawn and a pusher needle/sheath remains across the needle. Withdrawal pressure is applied to the two ends of the PTFE suture at the base of the needle (outside of the heart). This withdrawal pressure results in the development of a pre-formed knot that attains a significant size in the atrium, above the leaflet. The pusher needle is then withdrawn with the delivery instrument, and the length of the PTFE sutures are adjusted so that the amount of mitral regurgitation is minimized. Once this length is determined, the PTFE is secured to the outer surface of the heart using a pledget. 
         [0030]    In another embodiment, a single needle punctures the defective leaflet and deploys a coated, coiled guide wire having a suture woven through it. The suture is then pulled, causing the guide wire to configure into a predetermined shape above the leaflet. The instrument is then retracted out of the heart and the length of the guide wire/suture is adjusted. Once this length is determined, the guide wire/suture is affixed near the apex of the heart. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0031]    The above and other features, aspects, and advantages of the present disclosure are considered in more detail, in relation to the following description of embodiments thereof shown in the accompanying drawings, in which: 
           [0032]      FIG. 1  is a cut-away anterior view of the human heart showing the internal chambers, valves, and adjacent structures. 
           [0033]      FIG. 2  is a perspective view of a healthy mitral valve with the leaflets closed. 
           [0034]      FIG. 3  is a top view of a dysfunctional mitral valve with a visible gap between the leaflets. 
           [0035]      FIG. 4  shows a simplified view of a heart with four chambers and apex region. 
           [0036]      FIG. 5  illustrates the advancement of a device through an accessed region of the heart in accordance with the methods of embodiments herein. 
           [0037]      FIGS. 6   a - 6   c  illustrate an exemplary device according to embodiments herein. 
           [0038]      FIG. 7  illustrates an exemplary device according to embodiments herein. 
           [0039]      FIGS. 8   a - 8   f  show exemplary stages of the tip portion of an instrument according to an embodiment herein. 
           [0040]      FIGS. 9   a - 9   d  show an exemplary instrument according to another embodiment herein. 
           [0041]      FIGS. 10   a - 10   e  illustrate an additional embodiment herein. 
           [0042]      FIG. 11  shows an exemplary instrument according to an embodiment herein. 
           [0043]      FIGS. 12   a - 12   g  show an exemplary instrument according to another embodiment herein. 
           [0044]      FIGS. 13   a - 13   c  illustrates formation of a bulk knot in accordance with an embodiment herein. 
           [0045]      FIGS. 14   a - 14   c  show an additional embodiment herein. 
           [0046]      FIG. 15  illustrates an installed chord in accordance with an embodiment herein. 
           [0047]      FIG. 16  illustrates an expansile element according to another embodiment herein. 
           [0048]      FIG. 17  is another illustration of an expansile element according to embodiments herein. 
           [0049]      FIG. 18  illustrates use of a single needle device in accordance with the methods of embodiments herein. 
           [0050]      FIG. 19  illustrates use of an alternate single needle device in accordance with the methods of embodiments herein. 
           [0051]      FIG. 20  shows an additional embodiment herein. 
           [0052]      FIG. 21  illustrates locking steps in accordance with the methods of embodiments herein. 
           [0053]      FIG. 22  illustrates use of the device of embodiments herein in accordance with another method. 
       
    
    
     DETAILED DESCRIPTION 
       [0054]    In accordance with the methods of embodiments herein, the heart may be accessed through one or more openings made by a small incision(s) in a portion of the body proximal to the thoracic cavity, for instance, in between one or more of the ribs of the rib cage, proximate to the xyphoid appendage, or via the abdomen and diaphragm. Access to the thoracic cavity may be sought so as to allow the insertion and use of one or more thorascopic instruments, while access to the abdomen may be sought so as to allow the insertion and use of one or more laparoscopic instruments. Insertion of one or more visualizing instruments may then be followed by transdiaphragmatic access to the heart. Additionally, access to the heart may be gained by direct puncture (i.e., via an appropriately sized needle, for instance an 18 gauge needle) of the heart from the xyphoid region. Access may also be achieved using percutaneous means. Accordingly, the one or more incisions should be made in such a manner as to provide an appropriate surgical field and access site to the heart. See for instance, Full-Spectrum Cardiac Surgery Through a Minimal Incision Mini-Stemotomy (Lower Half) Technique Doty et al. Annals of Thoracic Surgery 1998; 65(2): 573-7 and Transxiphoid Approach Without Median Stemotomy for the Repair of Atrial Septal Defects, Barbero-Marcial et al. Annals of Thoracic Surgery 1998; 65(3): 771-4 which are specifically incorporated in their entirety herein by reference. 
         [0055]    After prepping and placing the subject under anesthesia a transesophageal echocardiogram (TEE) (2D or 3D), a transthoracic echocardiogram (TTE), intracardiac echo (ICE), or cardio-optic direct visualization (e.g., via infrared vision from the tip of a 7.5 F catheter) may be performed to assess the heart and its valves. A careful assessment of the location and type of dysfunction on the TEE, TTE, or other such instrument, facilitates the planning of the appropriate surgical procedure to be performed. The use of TEE, TTE, ICE, or the like, can assist in determining if there is a need for adjunctive procedures to be performed on the leaflets and subvalvular apparatus and can indicate whether a minimally invasive approach is advisable. 
         [0056]    Once a minimally invasive approach is determined to be advisable, one or more incisions are made proximate to the thoracic cavity so as to provide a surgical field of access. The total number and length of the incisions to be made depend on the number and types of the instruments to be used as well as the procedure(s) to be performed. The incision(s) should be made in such a manner so as to be minimally invasive. By “minimally invasive” is meant in a manner by which an interior organ or tissue may be accessed with as little as possible damage being done to the anatomical structure through which entry is sought. Typically, a minimally invasive procedure is one that involves accessing a body cavity by a small incision made in the skin of the body. By “small incision” is meant that the length of the incision generally should be about 1 cm to about 10 cm, or about 4 cm to about 8 cm, or about 7 cm in length. The incision may be vertical, horizontal, or slightly curved. If the incision is placed along one or more ribs, it should follow the outline of the rib. The opening should extend deep enough to allow access to the thoracic cavity between the ribs or under the sternum and is preferably set close to the rib cage and/or diaphragm, dependent on the entry point chosen. 
         [0057]    One or more other incisions may be made proximate to the thoracic cavity to accommodate insertion of a surgical scope. Such an incision is typically about 1 cm to about 10 cm, or about 3 cm to 7 cm, or about 5 cm in length and should be placed near the pericardium so as to allow ready access to and visualization of the heart. The surgical scope may be any type of endoscope, but is typically a thorascope or laparoscope, dependent upon the type of access and scope to be used. The scope generally has a flexible housing and at least a 16-times magnification. Insertion of the scope through an incision allows a practitioner to analyze and “inventory” the thoracic cavity and the heart so as to determine further the clinical status of the subject and plan the procedure. For example, a visual inspection of the thoracic cavity may reveal important functional and physical characteristics of the heart, and will indicate the access space (and volume) required at the surgical site and in the surgical field in order to perform the reparative cardiac valve procedure. At this point, the practitioner can confirm that access of one or more cardiac valves through the apex of the heart is appropriate for the particular procedure to be performed. 
         [0058]    With reference to  FIG. 4 , once a suitable entry point has been established, a suitable device such as one described herein, may be advanced into the body in a manner so as to make contact with the heart  10 . The advancement of the device may be performed in conjunction with sonography or direct visualization (e.g., direct transblood visualization). For instance, the device may be advanced in conjunction with TEE guidance or ICE so as to facilitate and direct the movement and proper positioning of the device for contacting the appropriate apical region of the heart. Typical procedures for use of echo guidance are set forth in Suematsu, Y., J. Thorac. Cardiovasc. Surg. 2005; 130:1348-1356, herein incorporated by reference in its entirety. 
         [0059]    One or more chambers  12 ,  14 ,  16 ,  18  in the heart  10  may be accessed in accordance with the methods disclosed herein. Access into a chamber in the heart may be made at any suitable site of entry but is preferably made in the apex region of the heart (e.g., at or adjacent to the apex  72 ). Typically, access into the left ventricle  14 , for instance, to perform a mitral valve repair, is gained through making a small incision into the apical region, close to (or slightly skewed toward the left of) the median axis  74  of the heart  10 . Typically, access into the right ventricle  18 , for instance, to perform a tricuspid valve repair, is gained through making a small incision into the apical region, close to or slightly skewed toward the right of the median axis  74  of the heart  10 . Generally, an apex region of the heart is a bottom region of the heart that is within the left or right ventricular region but is distal to the mitral valve  22  and tricuspid valve  26  and toward the tip or apex  72  of the heart  10 . More specifically, an “apex region” of the heart is within a few centimeters to the right or to the left of the septum  20  of the heart  10 . Accordingly, the ventricle can be accessed directly via the apex  72 , or via an off apex location that is in the apical region, but slightly removed from the apex  72 , such as via a lateral ventricular wall, a region between the apex and the base of a papillary muscle, or even directly at the base of a papillary muscle. Typically, the incision made to access the appropriate ventricle of the heart is no longer than about 1 mm to about 5 cm, from 2.5 mm to about 2.5 cm, from about 5 mm to about 1 cm in length. 
         [0060]    As explained above, both the mitral valve  22  and tricuspid valve  26  can be divided into three parts—an annulus, leaflets, and a sub-valvular apparatus. If the valve is functioning properly, when closed, the free margins of the leaflets come together and form a tight junction the arc of which, in the mitral valve, is known as the line of coaptation. The normal mitral and tricuspid valves open when the ventricles relax allowing blood from the left atrium to fill the decompressed ventricle. When the ventricle contracts, the increase in pressure within the ventricle causes the valve to close, thereby preventing blood from leaking into the atrium and assuring that all of the blood leaving the ventricle is ejected through the aortic valve  24  and pulmonic valve  28  into the arteries of the body. Accordingly, proper function of the valves depends on a complex interplay between the annulus, leaflets, and subvalvular apparatus. Lesions in any of these components can cause the valve to dysfunction and thereby lead to valve regurgitation. As set forth above, regurgitation occurs when the leaflets do not coapt at peak contraction pressures. As a result, an undesired back flow of blood from the ventricle into the atrium occurs. 
         [0061]    Once the malfunctioning cardiac valve has been assessed and the source of the malfunction verified, a corrective procedure can be performed. Various procedures can be performed in accordance with the methods of the disclosure herein in order to effectuate a cardiac valve repair, which will depend on the specific abnormality and the tissues involved. 
         [0062]    In one embodiment, a method of the present disclosure includes the implantation of one or more artificial chordae tendineae into one or more leaflets of a malfunctioning mitral valve  22  and/or tricuspid valve  26 . It is to be noted that, although the following procedures are described with reference to repairing a cardiac mitral or tricuspid valve by the implantation of one or more artificial chordae, the methods herein presented are readily adaptable for various types of leaflet repair procedures well-known and practiced in the art, for instance, an Alfieri procedure. In general, the methods herein will be described with reference to a mitral valve  22 . 
         [0063]    As illustrated in  FIG. 5 , in accordance with the methods of the present disclosure, once an appropriate incision has been made in the apex region of the heart, for instance, in the apex  72 , a suitable instrument  75  is then introduced into the ventricle  14  of the heart and advanced in such a manner so as to contact one or more cardiac tissues (for instance, a leaflet, an annulus, a cord, a papillary muscle, or the like) that are in need of repair. Sonic guidance, for instance, TEE guidance or ICE, may be used to assist in the advancement of the device into the ventricle and the grasping of the cardiac tissue with the device. Direct trans-blood visualization may also be used. 
         [0064]    A suitable instrument  75 , such as the one presented in  FIGS. 5 ,  6   a - 6   c , and  7 , will typically include an elongate member  78  with a functional distal portion  81  having a tip  84  configured for repairing a cardiac valve tissue, for instance, a mitral valve leaflet  52 ,  54 . The functional distal portion  81  of the device is configured for performing one or more selected functions, such as grasping, suctioning, irrigating, cutting, suturing, or otherwise engaging a cardiac tissue. Using a manipulatable handle portion  87 , the instrument  75  is then manipulated in such a manner so that a selected cardiac tissue (for instance, a papillary muscle, one or more leaflet tissues, chordae tendineae, or the like) is contacted with the functional distal portion  81  of the instrument  75  and a repair effectuated, for instance, a mitral or tricuspid valve repair. 
         [0065]    In one embodiment, the instrument  75  is designed to extend and contract with the beat of the heart. During systolic contraction, the median axis  74  of the heart  10  shortens. The distance from the apex  72  of the heart (where the device is inserted) to the mitral leaflet  52 ,  54  varies by 1-2 cm with each heartbeat. Accordingly, the instrument  75  is designed such that the tip  84  of the device (i.e. the part that contacts the mitral leaflet  52 ,  54 ) is “floating” wherein each systole is associated with approximately 1-2 cm of outward extension of the device. Referring to  FIGS. 6   a - 6   c , the instrument  75  includes an inner tube  89  and an outer tube  91 . The inner tube  89  is configured to slide within the outer tube  91 . A handle  87  is attached to the outer tube  91 . A resilient element  94 , such as a spring is present so that, as the outer tube  91  is advanced and the tip  84  makes contact with the leaflet  52 ,  54 , the elongate portion  78 , being connected to the inner tube  89 , pushes against the resilient element  94 . With forward pressure predetermined by the resilient element  94 , once the tip  84  comes in contact with the leaflet  52 ,  54 , even though the user continues to advance the instrument  75 , the amount of pressure applied by the tip to the leaflet  52 ,  54  will remain constant as a result of the presence of the resilient element  94 . The resilient element  94  allows a defined, constant forward force on the leaflet  52 ,  54 . A user may feel contact, but will also be able to confirm visually that the resilient element  94  is extending and contracting. 
         [0066]    While a smaller seating surface enables the tip  84  to be more easily localized, it may be more likely to perforate the leaflet. A larger seating surface is more likely to remain in the selected location, but is harder to land on the leaflet  52 ,  54 . Accordingly, in some embodiments, the delivery system may have a blunt end, to avoid pushing the entire device through the leaflet; to that end, a device with an expandable balloon  88  at the distal end, such as shown in  FIG. 7 , may be provided. 
         [0067]    The inflatable balloon  88  is provided at the tip  84 . The balloon  88  can distribute pressure more widely on the underside of the leaflet  52 ,  54 , and minimize the likelihood that the leaflet will be perforated unintentionally by the device. Such a balloon  88  can be configured to surround the tip  84 , thereby providing a broader seating surface against the leaflet. Once the instrument  75  is inserted, the balloon  88  can be inflated using methods known in the art. For example, the instrument  75  may include an inner lumen  90  comprising annealed stainless steel surrounded by an outer tube  92  made of urethane or other flexible material. A clearance space  93  between the inner lumen  90  and the outer tube  92  provides an inflation lumen. The outer tube should be bonded at one end around the tip  84  and at the other end to a valve  95 , such as a Touhy valve. The valve  95  is tightened to the inner lumen  90 . An inflation port  98  is provided to enable inflation of the balloon  88 . In some embodiments, the balloon  88  may provide an expanded seating surface of approximately 6-7 mm. 
         [0068]    Preferably, characteristics of the end surface of the tip  84  include ease of location on the leaflet, tendency to remain in one location, does not harm the leaflet by penetration, and can serve as a platform to deploy one or more needles, as described below. 
         [0069]      FIGS. 8   a - 8   f  show exemplary stages of the tip portion  84  of an instrument  75  according to an embodiment of the present disclosure. In the embodiment illustrated in  FIGS. 8   a - 8   f , the tip  84  has two channels; each channel contains a needle. Preferably, one channel contains a larger needle, such as a 20-gauge and the other channel contains a smaller needle. It is not necessary that the needles be different sizes, nor is the needle gauge particular to the practice of this disclosure; other sizes may be used. In some embodiments, the snare described below could be a smaller gauge than the suture, allowing the needles to be the same size. Preferably, the two needles are as far apart as possible in the tip  84 , so as to make the resulting suture that is installed less likely to tear the leaflet. In  FIG. 8   a , the needles are retracted. In  FIG. 8   b , both needles puncture the mitral valve leaflet (not shown); first the snare needle  151 , then the suture needle  154 . As shown in  FIG. 8   c , a metal (steel, nitinol, or other material) snare  157  is advanced through the larger needle. The snare  157  is adapted so that the loop can be selectively retracted or extended within the larger needle. The snare  157  is further adapted so that once it emerges (on the atrial side of the leaflet), it will deform in a predetermined manner, such as approximately a 90-degree bend, and is in position to capture a PTFE suture. While these steps may occur in rapid sequence, the snare  157  should not emerge until both needles have punctured the mitral valve leaflet. Preferably, the snare  157  includes a directional handle so that it is always deployed toward the center of the tip  84 .  FIG. 8   d  shows a PTFE suture  160  that is injected through the smaller needle (21 or 22 gauge) and passes through the deployed snare  157 . Preferably, heparinized saline is used to inject the PTFE suture  160 . As shown in  FIG. 8   e , the snare  157  is withdrawn into the 20-gauge needle, capturing the PTFE suture  160 . In  FIG. 8   f , the device is removed, leaving a PTFE suture in the leaflet. An alternate approach would be to advance a metal guide wire through the smaller needle, grasp it, and pull it back. The PTFE suture could then be tied to the guide wire and pulled through. 
         [0070]      FIG. 9  illustrates another embodiment using a “between the leaflets” approach for grasping and attaching a suture to a mitral valve leaflet  52 ,  54 . In this embodiment, a shafted instrument  100  is inserted between two mitral valve leaflets  52 ,  54 , as shown in  FIG. 9   a .  FIG. 9   b  shows a snare  103  and a stiff “upper stabilizer”  106  deployed at the end of the instrument  100 . Preferably, the snare  103  extends at approximately a 90-degree angle from the shaft  109 . Typically, the upper stabilizer  106  will have an angle of approximately 70-80° from the shaft. A user then pulls the instrument  100  back until the upper stabilizer  106  lands on the mitral leaflet  52 . Essentially, the leaflet  52  is stabilized by the shaft  109  (on the leading edge of the leaflet) and the snare stabilizer  106 . Next, as shown in  FIG. 9   c , a second stabilizer (a narrow snare or prong)  112  is deployed below the leaflet  52 . Typically, the second stabilizer  112  will have an angle of approximately 50-60° from the shaft. The second stabilizer  112  is progressively advanced toward the upper stabilizer  106 . The leaflet  52  is “grabbed” by the two stabilizers  106 ,  112 . Once the leaflet  52  is grasped, as shown in  FIG. 9   d , a needle  115  is ejected at an angle from the shaft  109 . The needle  115  penetrates the leaflet  52 , and passes through the upper stabilizer  106  and the snare  103 . A PTFE suture is then injected through the needle  115  and captured by the snare  103 . The needle  115  can then be retracted while the snare  103  holds the suture. Next, the snare  103  is withdrawn with the suture penetrating through the leaflet  52 . The lower stabilizer  112  is withdrawn, followed by the upper stabilizer  106 . 
         [0071]    Another embodiment is shown in  FIG. 10 . A slotted needle  165  is wrapped with a PTFE suture. The needle  165  can be as small as 22 gauge. In some embodiments, the needle  165  may be electropolished to make it smooth. Referring to  FIG. 10   a , a suture  168  is prepared on the needle  165 . Preferably, the suture is made of PTFE material. One end of the suture  168  emerges from a distal end  171  of the needle  165 , and another end emerges from a slot  172 . The suture  168  may have a simple knot  173  (see  FIG. 12 ) where it emerges from the distal end  171  of the needle  165  and another knot at the end of the wrapping near the slot  172 . In some embodiments, small, temporary silicone rings (not shown) may be used to hold the suture  168  at the distal and proximal ends. As shown in  FIG. 10   b , a first coil  175  is wound from the outside toward the inside (top to bottom). The suture  168  should wrapped tightly around the needle  165  for approximately 20-200 turns. Other numbers of turns may be used. As shown in  FIG. 10   c , a second coil  176  is wound from the outside toward the inside (bottom to top). Again, the suture  168  should be wrapped tightly around the needle  165  for approximately 20-200 turns. Other numbers of turns may be used. A short section may be left in the center for threading and completing the rest of the knot. The ends of the suture  168  may be crossed and looped from the end of the distal coil in the distal direction or in the direction of the proximal coil. The knot can be tightened by sliding the two coils  175 ,  176  to the center and twisting the coils to take up the slack in the needle slot, as shown in  FIG. 10   e . In some embodiments, a medical grade silicone may be used on the needle  165  and the wrapped suture  168  to allow smooth withdrawal of the needle  165  during subsequent procedure.  FIG. 11  shows a finished version of a needle  165  with a suture  168  wrapped thereon. 
         [0072]    Referring to  FIG. 12 , and particularly the portion labeled (a), the needle  165  has a suture  168  tightly wrapped around one end thereof. A pusher  177  or hollow guide wire may be provided on the needle  165 . As shown in  FIG. 12   b , the wrapped needle  165  is inserted into the heart toward the mitral valve leaflet  52 . The wrapped needle  165  can be advanced across the mitral valve leaflet  52  until the end of the wrapping, indicated by  179 , is in the atrium above the leaflet  52 , as shown in  FIG. 12   c , leaving a small hole. In  FIG. 12   d , the needle  165  is withdrawn, but the pusher  177  and suture  168  remain. In  FIG. 12   e , a withdrawal force applied to the ends of the suture  168  resulting in the transformation of the tightly wrapped coil of the suture  168  into a bulky knot  180  as shown in  FIG. 12   f . Lastly, as shown in  FIG. 12   g , the pusher  177  is withdrawn, leaving the permanent bulky knot  180 , which anchors the suture  168  to the leaflet  52 . In this embodiment, the resulting implant is made solely of a PTFE suture, which is a time-tested means of fixing the mitral valve. 
         [0073]    There are many possible configurations of PTFE material and needle to form the bulky knot  180 . For example, the suture  168  may form two or more loops, such as in  FIG. 14 . In some embodiments, the suture  168  may be double wrapped on the needle  165 . Alternatively, the needle  165  may be non-hollow; that is, a solid needle.  FIG. 13  illustrates how the simple bulky knot  180 , described above, is formed. In  FIG. 13   a , the suture  168  is deployed. In  FIG. 13   b , the withdrawal force applied to the ends of the suture  168  pulls the knot  173  toward the end of the wrapping  174 . Once the two ends meet, the bulky knot  180  remains, as shown in  FIG. 13   c.    
         [0074]    In other words, according to the “bulky knot” concept: a PTFE suture  168  (or any kind of suture, or perhaps even a “filament”) is wrapped tightly around a small-gauge needle  165 , near the tip. The needle  165  is then advanced through the valve leaflet  52 . A “pusher”  177  surrounds the needle  165  and extends to the level of the “wrap” of suture/filament. Once the sharp point end of the needle and the wrap/coil of suture/filament  179  has passed through the leaflet  52 , the needle  165  is withdrawn. This leaves the coil (s)  175 ,  176  unsupported. Tension on the ends of the filament/suture  168  at the base of the needle then cause a bulky knot  180  to form. Finally, the pusher  177  is pulled back, leaving a bulky knot  180  on the “far” side of the leaflet  52 . 
         [0075]      FIG. 14  illustrates an alternate embodiment of the bulky knot described above. An additional bulky knot  182  is created below the leaflet  52 . The additional bulky knot  182  will sandwich the leaflet  52  between two knots. The distance between the knots should be no more than the thickness of the leaflet  52 . As shown in  FIG. 14   b , a spacer  185  may be provided between the bulky knots  180 ,  182 . 
         [0076]    Referring to  FIG. 15 , once one or more bulky knots  180  have been implanted to one or more cardiac tissues, lengthening or shortening of the artificial chordae can be performed by knotting, tying, cutting, anchoring, and otherwise manipulating the cords in a manner so as to achieve the desired (e.g., optimal) length. Once the optimal length of the neochord is determined, the suture  168  can be tied off and/or anchored, outside of the apex  72 , by any means well known in the art, for instance, by tying one or more knots into the suture  168 . One or more pledgets  143  may also be used. 
         [0077]    According to embodiments herein, the bulky knot concept can be used for an Alfieri stitch; that is, an Alfieri stitch can be created by sequentially deploying a double helix knot on first one leaflet of the mitral valve (i.e., the anterior leaflet  52 ), followed by the posterior leaflet  54 , then tying the two together, using a knot pusher deployed from the apex  72 . 
         [0078]    Furthermore, while the embodiments disclosed herein are described with reference to a heart valve leaflet. The concepts are equally applicable to penetrating and applying similar knots to the annulus  60  of the valves. In some embodiments, several bulky knots  180  may be installed in the annulus  60  and tied together. 
         [0079]      FIG. 16  shows another embodiment in which an expansile element  121  has been created. One approach for the expansile element  121  is a standard guide wire  125  made of an elongated spring formed of steel, nitinol, or other material. The guide wire  125  may be coated with PTFE or other appropriate coating. Alternatively, the guide wire  125  may remain uncoated. The guide wire  125  should be appropriately sized, such as 0.9 mm. Other sizes may be used. The expansile element  121  includes a suture  128  in the core. Preferably, the suture  128  is made of PTFE. The suture  128  is woven through the guide wire  125  as illustrated in  FIG. 16  so that pulling on the suture  128  causes deformation of the tip of the expansile element  121  into a figure of 8 (or similar) configuration.  FIG. 17  shows the progression of the expansile element  121  from an inactivated form as shown in  FIG. 17   a  to a partially activated form in  FIG. 17   b , then to a fully activated form in  FIG. 17   c . The fully activated form may be in a spiral or helical shape or have one, two, three, or more loops, as desired. 
         [0080]    Using an expansile element  121 , a single-needle puncture procedure can be performed. As shown in  FIG. 18 , a neochord implant  131  that contains an expansile element  121  on the tip can be deployed once it has passed through the leaflet  52 . The neochord implant  131  is inside an appropriately sized needle  134 . The needle  134  may be 20-gauge, 19-gauge, 18-gauge, or other appropriate size. The needle  134  is used to penetrate the leaflet  52  and is then withdrawn, leaving the neochord implant  131  in place. The expansile element  121  is activated by pulling on the suture  128  causing deformation of the expansile element  121  at the tip into a predetermined configuration such as shown at  136 , which keeps the implant  131  in place. 
         [0081]    In some embodiments, the expansile element  121  may be self-forming; that is, the expansile element  121  can be made of a pre-shaped “memory” metal that is inserted into the needle  134 . Withdrawal of the needle  134  allows the expansile element  121  to form its required shape. 
         [0082]    Alternatively, as shown in  FIG. 19 , an appropriately sized needle  137  or fine wire may be located inside the neochord implant  131 . As above, the needle  137  is used to penetrate the leaflet  52  and is then withdrawn, leaving the neochord implant  131  in place. An advantage of having the needle  137  inside the implant  131  is that it enables tighter tolerance between the implant  131  and the leaflet  52 . Additionally, if a fine wire is used, it could also be used to activate the expansile element  121  instead of the suture  128 . 
         [0083]      FIG. 20  shows an alternate configuration for the expansile element  121 . An additional loop  140  is created below the leaflet  52 . The additional loop  140  will sandwich the leaflet  52  between two loops of the implant  131 . The distance between the loops should be no more than the thickest a leaflet  52  could be. As the additional loop  140  is formed, it will conform to the thickness of the leaflet  52 . 
         [0084]    Referring to  FIG. 21 , once one or more implants  131  have been implanted to one or more cardiac tissues, the implantation device is removed through the access (e.g., via the access port), and the tail ends of the suture(s)  128  are trailed therethrough. Artificial chordae lengthening or shortening can be performed by knotting, tying, cutting, anchoring, and otherwise manipulating the cords in a manner so as to achieve the desired (e.g., optimal) length. Once the optimal length of the neochord is determined, the suture  128  can be tied off and/or anchored, outside of the apex  72 , by any means well known in the art, for instance, by tying one or more knots into the suture  128 . One or more pledgets  143  may also be used. 
         [0085]    In another approach, the neochord implant  131  of the present disclosure herein can be used in an edge-to-edge (Alfieri) repair, as shown in  FIG. 22 . A first implant  131  is deployed on one leaflet  52 . A second implant  131  is deployed on the second leaflet  54 . The two implants are then banded together to create adjoining edges. 
         [0086]    The sutures that are to be implanted (for instance, so as to function as artificial chordae tenidinae or neochords) may be fabricated from any suitable material, such as but not limited to: polytetrafluoroethylene (PTFE), nylon, Gore-Tex, Silicone, Dacron, or the like. With respect to the implantation of artificial chordae, the particular function of the replacement cord is dependent upon the configuration, physical characteristics and relative positioning of the structure(s). In certain embodiments, the structures act to restrain the abnormal motion of at least a portion of one or more of the valve leaflets. In other embodiments, the prosthetic chordae provide a remodeling as well as a leaflet restraint function where the latter may address latent or residual billowing of the leaflet body and/or latent or residual prolapsing of the leaflet edge, either of which may result from the remodeling itself or from a physiological defect. 
         [0087]    It is to be noted that a fundamental challenge in successfully replacing one or more chordae tendineae and restoring proper functioning of a cardiac valve, is determining the appropriate artificial cord length and securing the artificial cord at a location so as to ensure the optimal replacement chordae length. The valve will not function properly if the length of the artificial cord is too long or too short. Because the heart is stopped using conventional techniques, it is virtually impossible to ensure that the cords are of the correct length and are appropriately spaced inside the ventricle to produce a competent valve. Accordingly, methods of the disclosure herein include the measuring and determining of the optimal arrangement, length, placement, and configuration of an implanted suture, for instance, a replacement cord length, while the heart is still beating and, typically, before the access site of the heart is closed. An optimal arrangement of a suture, for instance, an optimal cord length, is that arrangement that effects said repair, for instance, by minimizing reperfusion as determined by means well known in the art, for instance, by direct echo guidance. 
         [0088]    Therefore, in accordance with the methods of the disclosure herein, once one or more artificial chordae have been implanted to one or more cardiac tissues, the implantation device is removed through the access (e.g., via the access port), and as stated above, the tail ends of the suture(s) are trailed therethrough. The optimal length of the implanted suture(s) (i.e., neochord) can then be determined by manipulating the ends of the suture(s) in a graded and calibrated fashion that is akin to manipulating a marionette. The manipulation of the artificial chordae may be done in conjunction with audio or visual assistance means, for instance, direct echo (e.g., echocardiographic) guidance, by which the degree and extent of regurgitation can be measured while the chordal length is being manipulated, so as to determine a chordal length that minimizes any observed regurgitation. Since, in a preferred embodiment, the heart is still beating the degree of cardiac regurgitation can be evaluated real time and the optimal neochord(s) length determined. Accordingly, an optimal cord length is a cord length that is determined, for instance, by direct echo guidance, to minimize or at least reduce cardiac valve regurgitation. Artificial chordae lengthening or shortening can be performed, as described above, by knotting, tying, cutting, anchoring, and otherwise manipulating the cords in a manner so as to achieve the desired (e.g., optimal) length. Once the optimal length of the neochord is determined, the sutures can be tied off and/or anchored, outside of the apex, by any means well known in the art, for instance, by tying one or more knots into the suture. One or more pledgets may also be used. 
         [0089]    Once the corrective procedures are completed, the repaired valve may be further assessed, and if the repair is deemed satisfactory, the one or more devices (e.g., cannulae, sheath, manifold, access port, etc.) are removed, the access closed, as described above, and the percutaneous incisions are closed in a fashion consistent with other cardiac surgical procedures. For instance, one or more purse-string sutures may be implanted at the access site of the heart and/or other access sites, so as to close the openings. 
         [0090]    It is further contemplated that the devices and methods disclosed herein can be used in procedures outside the heart. That is, while the embodiments have been described with reference to a heart valve, the devices and methods described above may be used in any procedure that requires penetrating a tissue and forming a knot on the far side thereof. 
         [0091]    The present disclosure has been described with references to specific embodiments. While particular values, relationships, materials and steps have been set forth for purposes of describing concepts of the disclosure herein, it will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the disclosure herein as shown in the disclosed embodiments without departing from the spirit or scope of the basic concepts and operating principles of the disclosure herein as broadly described. It should be recognized that, in the light of the above teachings, those skilled in the art could modify those specifics without departing from the disclosure herein taught herein. Having now fully set forth certain embodiments and modifications of the concept underlying the present disclosure herein, various other embodiments as well as potential variations and modifications of the embodiments shown and described herein will obviously occur to those skilled in the art upon becoming familiar with such underlying concept. It is intended to include all such modifications, alternatives and other embodiments insofar as they come within the scope of the appended claims or equivalents thereof. It should be understood, therefore, that the disclosure herein might be practiced otherwise than as specifically set forth herein. Consequently, the present embodiments are to be considered in all respects as illustrative and not restrictive.