Abstract:
An assembly and method for effecting the condition of a mitral valve annulus of a heart includes a guide wire configured to be fed into the coronary sinus of the heart, and a mitral valve annulus therapy device configured to be slidingly received on the guide wire and advanced into the coronary sinus of the heart on the guide wire. A guide tube may further be employed for guiding the device into the coronary sinus. An introducer which may be employed for pushing the device into or pulling device out of the heart has a mechanism for releasably locking to the device. This enables substitution of the device if needed. Also, the crossover point of the circumflex artery and coronary sinus may be determined and avoided when the device is deployed.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention generally relates to a device, system and method for treating a deformed heart valve. The present invention more particularly relates to a device, system and method for constricting or reforming a mitral valve annulus from within the coronary sinus to correct mitral valve dilation without blocking blood flow in the circumflex artery and which may be implemented using a guide wire within the coronary sinus to effect accurate device deployment and substitution.  
         BACKGROUND OF THE INVENTION  
         [0002]    The human heart generally includes four valves. Of these valves, a most critical one is known as the mitral valve. The mitral valve is located in the left atrial ventricular opening between the left atrium and left ventricle. The mitral valve is intended to prevent regurgitation of blood from the left ventricle into the left atrium when the left ventricle contracts. In preventing blood regurgitation the mitral valve must be able to withstand considerable back pressure as the left ventricle contracts.  
           [0003]    The valve cusps of the mitral valve are anchored to muscular wall of the heart by delicate but strong fibrous cords in order to support the cusps during left ventricular contraction. In a healthy mitral valve, the geometry of the mitral valve ensures that the cusps overlie each other to preclude regurgitation of the blood during left ventricular contraction.  
           [0004]    The normal functioning of the mitral valve in preventing regurgitation can be impaired by dilated cardiomyopathy caused by disease or certain natural defects. For example, certain diseases may cause dilation of the mitral valve annulus. This can result in deformation of the mitral valve geometry to cause ineffective closure of the mitral valve during left ventricular contraction. Such ineffective closure results in leakage through the mitral valve and regurgitation. Diseases such as bacterial inflammations of the heart or heart failure can cause the aforementioned distortion or dilation of the mitral valve annulus. Needless to say, mitral valve regurgitation must not go uncorrected.  
           [0005]    One method of repairing a mitral valve having impaired function is to completely replace the valve. This method has been found to be particularly suitable for replacing a mitral valve when one of the cusps has been severely damaged or deformed. While the replacement of the entire valve eliminates the immediate problem associated with a dilated mitral valve annulus, presently available prosthetic heart valves do not possess the same durability as natural heart valves.  
           [0006]    Various other surgical procedures have been developed to correct the deformation of the mitral valve annulus and thus retain the intact natural heart valve function. These surgical techniques involve repairing the shape of the dilated or deformed valve annulus. Such techniques, generally known as annuloplasty, require surgically restricting the valve annulus to minimize dilation. Here, a prosthesis is typically sutured about the base of the valve leaflets to reshape the valve annulus and restrict the movement of the valve annulus during the opening and closing of the mitral valve.  
           [0007]    Many different types of prostheses have been developed for use in such surgery. In general, prostheses are annular or partially annular shaped members which fit about the base of the valve annulus. The annular or partially annular shaped members may be formed from a rigid material, such as a metal, or from a flexible material.  
           [0008]    While the prior art methods mentioned above have been able to achieve some success in treating mitral regurgitation, they have not been without problems and potential adverse consequences. For example, these procedures require open heart surgery. Such procedures are expensive, are extremely invasive requiring considerable recovery time, and pose the concomitant mortality risks associated with such procedures. Moreover, such open heart procedures are particularly stressful on patients with a comprised cardiac condition. Given these factors, such procedures are often reserved as a last resort and hence are employed late in the mitral regurgitation progression. Further, the effectiveness of such procedures is difficult to assess during the procedure and may not be known until a much later time. Hence, the ability to make adjustments to or changes in the prostheses to obtain optimum effectiveness is extremely limited. Later corrections, if made at all, require still another open heart surgery.  
           [0009]    An improved therapy to treat mitral regurgitation without resorting to open heart surgery has recently been proposed. This is rendered possible by the realization that the coronary sinus of a heart is near to and at least partially encircles the mitral valve annulus and then extends into a venous system including the great cardiac vein. As used herein, the term “coronary sinus” is meant to refer to not only the coronary sinus itself but in addition, the venous system associated with the coronary sinus including the great cardiac vein. The therapy contemplates the use of a device introduced into the coronary sinus to reshape and advantageously effect the geometry of the mitral valve annulus.  
           [0010]    The device includes a resilient member having a cross sectional dimension for being received within the coronary sinus of the heart and a longitudinal dimension having an unstressed arched configuration when placed in the coronary sinus. The device partially encircles and exerts an inward pressure on the mitral valve. The inward pressure constricts the mitral valve annulus or at least a portion of it to essentially restore the mitral valve geometry. This promotes effective valve sealing action and eliminates mitral regurgitation.  
           [0011]    The device may be implanted in the coronary sinus using only percutaneous techniques similar to the techniques used to implant cardiac leads such as pacemaker leads. The device is implanted using an elongated introducer configured for being releasably coupled to the device. The introducer is preferably flexible to permit it to advance the device into the heart and into the coronary sinus through the coronary sinus ostium. To promote guidance, an elongated sheath is first advanced into the coronary sinus. Then, the device and introducer are moved through a lumen of the sheath until the device is in position within the coronary sinus. Because the device is formed of resilient material, it conforms to the curvatures of the lumen as it is advanced through the sheath. The sheath is then partially retracted to permit the device to assume its unstressed arched configuration. Once the device is properly positioned, the introducer is then decoupled from the device and retracted through the sheath. The procedure is then completed by the retraction of the sheath. As a result, the device is left within the coronary sinus to exert the inward pressure on the mitral valve to restore mitral valve geometry.  
           [0012]    The foregoing therapy has many advantages over the traditional open heart surgery approach. Since the device, system and method may be employed in a comparatively noninvasive procedure, mitral valve regurgitation may be treated at an early stage in the mitral regurgitation progression. Further, the device may be placed with relative ease by any minimally invasive cardiologist. Still further, since the heart remains completely intact throughout the procedure, the effectiveness of the procedure may be readily determined. Moreover, should adjustments be deemed desirable, such adjustments may be made during the procedure and before the patient is sent to recovery.  
           [0013]    Unfortunately, the human anatomy does impose some obstacles to this recently proposed procedure for treating mitral regurgitation. More specifically, the human heart includes a coronary artery which descends from the aorta. One branch of the coronary artery is the circumflex artery which, in turn, includes the left marginal branch of the circumflex artery. As used herein, the term “circumflex artery” is taken to include the circumflex artery itself or any branch therefrom. The circumflex artery extends distally generally along the coronary sinus but at a point proximal to the coronary artery, it passes under the coronary sinus. The circumflex artery supports blood flow important to the viability of the heart. Hence, reduction in this blood flow must be avoided. As a result, a device placed in the coronary sinus must not be permitted to extend within the coronary sinus beyond the crossover point of the circumflex artery and the coronary sinus to avoid constriction of the circumflex artery. This contemplates the need to know the location of the circumflex artery and coronary sinus crossover point. It also contemplates accurate positioning of the device within the coronary sinus to assure that the device does not extend over the circumflex artery.  
           [0014]    The above is further compounded by the fact that the human heart anatomy and indeed the mitral valve condition will vary from patient to patient. Hence, after deployment of an initial therapy device, the initial device effectiveness must be tested. Should a further device having different properties or configuration be deemed more efficacious, there must be provided a way to easily remove the initial device and then deploy the further device with the same deployment accuracy to avoid the crossover of the circumflex artery with the coronary sinus.  
           [0015]    The present invention addresses these issues. The present invention provides a therapy system and procedure which enables avoidance of the crossover of the circumflex artery with the coronary sinus by permitting accurate placement of an initial device or any substitute device within the coronary sinus. Further to that end, the present invention enables the crossover point of the circumflex artery with the coronary sinus to be readily determined and, if desired, continuously observed during the therapy procedure. Still further, the present invention contemplates a mitral valve therapy device which is configured to avoid constricting the circumflex artery even though it passes over the circumflex artery within the coronary sinus.  
         SUMMARY OF THE INVENTION  
         [0016]    The present invention provides an assembly for effecting the condition of a mitral valve annulus of a heart. The assembly includes a guide wire configured to be fed into the coronary sinus of the heart and a mitral valve annulus therapy device configured to be slidably received on the guide wire and advanced into the coronary sinus of the heart on the guide wire.  
           [0017]    The assembly may further include an elongated introducer configured to be slidingly received on the guide wire proximal to the device. The introducer may be releasably locked to the device during the deployment of the device within the coronary sinus. The assembly may further include a guide tube having an inner lumen dimensioned for receiving the guide wire and the device and introducer when the device and introducer are slidingly received on the guide wire.  
           [0018]    The assembly may still further include an elongated flexible member which is visible under X ray fluoroscopy and which may be advanced into the circumflex artery. The guide wire may also be visible under X ray fluoroscopy to reveal, under X ray fluoroscopic examination, the crossover point of the circumflex artery and the coronary sinus.  
           [0019]    The present invention still further provides a mitral valve annulus device for reshaping the mitral valve annulus to effect the condition of a mitral valve annulus of a heart. The device includes a resilient member having a cross sectional dimension for being received within the coronary sinus of a heart and having a longitudinal dimension having an arched configuration for partially encircling the mitral valve and exerting an inward pressure on the mitral valve when within the coronary sinus adjacent the mitral valve for reshaping at least a portion of the mitral valve annulus. The device includes a distal end having a bent portion to avoid exerting pressure on the circumflex artery at the crossover point of the circumflex artery and the coronary sinus.  
           [0020]    The present invention further provides a mitral valve annulus therapy device including a generally C-shaped clip member formed of resilient material for exerting a substantially radially inward force on the mitral valve annulus when placed in the coronary sinus of a heart about and adjacent to the mitral valve. The device has a distal end including a bent portion to avoid exerting pressure on the circumflex artery at the crossover point of the circumflex artery and the coronary sinus.  
           [0021]    The present invention further provides a method of determining the crossover point of the circumflex artery and coronary sinus of a heart. The method includes the steps of inserting a first elongated flexible rod into the coronary sinus, the first rod being visible under X ray fluoroscopy, inserting a second elongated flexible rod into the circumflex artery, the second rod being visible under X ray fluoroscopy, and subjecting the heart to X ray fluoroscopic examination to determine the crossover point of the first and second rods.  
           [0022]    The present invention further provides a method of deploying a mitral valve annulus reshaping device within the coronary sinus of a heart. The method includes the steps of inserting a guide wire into the coronary sinus of the heart, and advancing an elongated mitral valve annulus constricting device on the guide wire and into the coronary sinus into a position such that the device at least partially encircles the mitral valve of the heart.  
           [0023]    The advancing step may further include the steps of slidingly mounting an elongated flexible introducer onto the guide wire proximal to the device, engaging the distal end of the introducer with the proximal end of the device, and pushing the device distally into the coronary sinus with the introducer. After the device is deployed in the coronary sinus, the introducer may be withdrawn.  
           [0024]    During deployment of the device, the introducer may be releasably locked to the device. After deployment, but before the introducer is withdrawn, the introducer may be released from the device.  
           [0025]    The method may further include the steps of providing an elongated flexible guide tube having an inner lumen, the inner lumen having a cross sectional dimension greater than the cross sectional dimension of the guide wire, and feeding the guide tube into the coronary sinus of the heart over the guide wire with the guide wire within the inner lumen of the guide tube. Thereafter, the device may be pushed along the guide wire and within the guide tube.  
           [0026]    The present invention further provides a method of deploying a mitral valve annulus therapy device within the coronary sinus of a heart. The method includes the steps of inserting a first wire into the circumflex artery of the heart, the first wire being visible under X ray fluoroscopy, inserting a second wire into the coronary sinus of the heart, the second wire being visible under X ray fluoroscopy, subjecting the heart to X ray fluoroscopic examination to visualize the crossover point of the first and second wires, and deploying an elongated mitral valve annulus therapy device within the coronary sinus in a position such that the distal end of the device is proximal to the crossover point of the first and second wires. Preferably, during deployment, the device is guided by the second wire into the coronary sinus.  
           [0027]    The method may further include the steps of slidingly mounting an elongated flexible introducer onto the second wire proximal to the device, engaging the distal end of the introducer with the proximal end of the device, and pushing the device distally into the coronary sinus with the introducer. During deployment, the introducer may be releasably locked to the device. After deployment, the introducer may be released from the device and withdrawn.  
           [0028]    The method may further include the steps of providing an elongated flexible guide tube having an inner lumen, the inner lumen having a cross sectional dimension greater than the cross sectional dimension of the second wire, and the guide tube being transparent to X ray fluoroscopy, and feeding the guide tube into the coronary sinus of the heart over the second wire with the second wire within the inner lumen of the guide tube. The device may then be pushed along the second wire by the introducer and within the guide tube until it reaches a desired position within the coronary sinus.  
           [0029]    The present invention still further provides a method of deploying a constricting device within the coronary sinus of a heart to reshape the mitral valve annulus of the heart. The method includes the steps of providing an elongated flexible guide wire having a cross sectional dimension, feeding the guide wire into the coronary sinus of the heart, providing an elongated flexible guide tube having an inner lumen, the inner lumen having a cross sectional dimension greater than the cross sectional dimension of the guide wire, and feeding the guide tube into the coronary sinus of the heart over the guide wire with the guide wire within the inner lumen of the guide tube.  
           [0030]    The method further includes the steps of providing a mitral valve annulus constricting device configured to be slidingly received on the guide wire and within the inner lumen of the guide tube, the device including a proximal end, providing a flexible elongated introducer configured to be slidingly received on the guide wire and within the inner lumen of the guide tube, the introducer having a distal end, and placing the device onto the guide wire.  
           [0031]    The method still further includes the steps of placing the introducer onto the guide wire, engaging the distal end of the introducer with the proximal end of the device, pushing the device with the introducer in a distal direction along the guide wire and within the guide tube until the device is at least partially encircling the mitral valve within the coronary sinus of the heart, and withdrawing the introducer and the guide tube from the heart.  
           [0032]    During deployment of the device, the introducer may be releasably locked to the device. After deployment, but before the introducer is withdrawn, the introducer may be released from the device. The effectiveness of the device may then be tested.  
           [0033]    Should a replacement device be required, further steps to replace the device with a substitute device may be taken. Those steps may include feeding the guide tube into the coronary sinus of the heart over the guide wire and the device, feeding the introducer over the guide wire and into the guide tube, releasably locking the distal end of the introducer to the proximal end of the device, and retracting the introducer and device in a proximal direction and from the guide tube. When the device has been removed, a replacement device may then be deployed in the same manner as the initial device was deployed. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0034]    The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with further aspects and advantages thereof, may best be understood by making reference to the following description taken in conjunction with the accompanying drawings, and the several figures of which like reference numerals identify identical elements, and wherein:  
         [0035]    [0035]FIG. 1 is a superior view of a human heart with the atria removed;  
         [0036]    [0036]FIG. 2 is a perspective view of a mitral valve annulus constricting device embodying the present invention;  
         [0037]    [0037]FIG. 3 is a perspective view of an assembly for deploying a mitral valve constricting device in accordance with a preferred embodiment of the present invention;  
         [0038]    [0038]FIG. 4 is another perspective view of the assembly of FIG. 3;  
         [0039]    [0039]FIG. 5 is a superior view of a human heart similar to that of FIG. 1 and illustrating a method of determining the crossover point of the circumflex artery and the coronary sinus in accordance with a preferred embodiment of the present invention;  
         [0040]    [0040]FIG. 6 is another view of a human heart illustrating the method of determining the crossover point of the circumflex artery and the coronary sinus in accordance with the present invention;  
         [0041]    [0041]FIG. 7 is another superior view of a human heart illustrating deployment of a mitral valve therapy device in accordance with the preferred embodiment of the present invention;  
         [0042]    [0042]FIG. 8 is another superior view of a human heart illustrating an implanted mitral valve therapy device embodying the present invention;  
         [0043]    [0043]FIG. 9 is another superior view of a human heart illustrating another mitral valve therapy device embodying the present invention implanted in the heart;  
         [0044]    [0044]FIG. 10 is a perspective view of another mitral valve annulus device embodying the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0045]    Referring now to FIG. 1, it is a superior view of a human heart  10  with the atria removed to expose the mitral valve  12 , the coronary sinus  14 , the coronary artery  15 , and the circumflex artery  17  of the heart  10  to lend a better understanding of the present invention. Also generally shown in FIG. 1 are the pulmonary valve  22 , the aortic valve  24 , and the tricuspid valve  26  of the heart  10 .  
         [0046]    The mitral valve  12  includes an anterior cusp  16 , a posterior cusp  18  and an annulus  20 . The annulus encircles the cusps  16  and  18  and maintains their spacing to provide a complete closure during a left ventricular contraction. As is well known, the coronary sinus  14  partially encircles the mitral valve  12  adjacent to the mitral valve annulus  20 . As is also known, the coronary sinus is part of the venus system of the heart and extends along the AV groove between the left atrium and the left ventricle. This places the coronary sinus essentially within the same plane as the mitral valve annulus making the coronary sinus available for placement of the mitral valve therapy device of the present invention therein.  
         [0047]    of particular importance is the physiological relationship of the coronary sinus  14  and the circumflex artery  17 . The circumflex artery  17  branches from the coronary artery  15  and supplies blood flow to critical tissue of the heart  10 . The circumflex artery passes beneath the coronary sinus  14  at a crossover point  19 . It is one aspect of the present invention to avoid constriction of blood flow through the circumflex artery  17  when a mitral valve therapy device is deployed in the coronary sinus  14 .  
         [0048]    [0048]FIG. 2 shows a mitral valve therapy device  30  embodying the present invention. As may be noted in FIG. 2, the device is elongated and has an arched configuration to at least partially encircle the mitral valve  12  adjacent to the mitral valve annulus  20  when implanted in the coronary sinus  14 . The device  30  has an unstressed preformed arched radius smaller than the radius of the dilated mitral valve annulus  20 . This causes the device  30  to constrict the mitral valve annulus and impart an inward, generally radial force designated by arrows  32  on the mitral valve annulus  20  when implanted in the coronary sinus of the heart. This force reshapes and returns the mitral valve annulus  20  to its original or substantially original geometry to permit the cusps  16  and  18  to more fully come together for sealing the left atrium during left ventricular contraction.  
         [0049]    The device  30  has a cross section dimension to be received by the coronary sinus. It is preferably formed of a resilient material permitting the device to be straightened and/or bent for being advanced into the coronary sinus. After being positioned within the coronary sinus, the device is permitted to assume its preformed arched configuration to act upon the mitral valve annulus as previously described. To that end, the device may be formed of, for example, Nitinol, a nickel titanium alloy, well known in the art. This material, as is well known, is capable of being preformed but manipulated to be straight or partially bent while having sufficient memory to return to its preformed configuration. Stainless steel is also among the materials which may be used in forming the device  30 . In order to be received within the coronary sinus, the device may have a cross sectional dimension of, for example, on the order of four or five french.  
         [0050]    With continued reference to FIG. 2, the device  30  has a distal end  34  and a proximal end  36 . Between the distal end  34  and proximal end  36  the device further includes a channel  38  which is aligned with a bore  40  extending through the distal end  34  and a bore  42  extending through the proximal end  36 . The proximal end  36  further includes an integral sleeve  44  which carries a protruding locking pin  46 . As will be seen subsequently, the bores  40  and  42  permit the device to be slidingly received by a guide wire during deployment of the device  30 . The guide wire, during deployment, is confined within the channel  38 .  
         [0051]    [0051]FIGS. 3 and 4 illustrate an assembly  50  for deploying or implanting the mitral valve therapy device  30 . The assembly  50  includes a guide wire  52 , a guide tube  54 , and an elongated introducer  56 .  
         [0052]    The guide wire  52  is preferably an elongated coil. It has an outer dimension to permit the guide wire  52  to be passed through the bores  40  and  42  of the device  30 . This enables the device  30  to be slidingly received on the guide wire  52  with the guide wire confined within the channel  38  of the device  30 .  
         [0053]    The guide tube  54  is elongated and formed of a flexible biocompatible material. It includes an inner lumen  55  permitting the device  30  and the introducer  56  to be received therein.  
         [0054]    The introducer  56  preferably takes the form of an elongated coil having an inner channel dimensioned to be received by and slid onto the guide wire  52 . At a distal end  58  the introducer includes a sleeve  60  which may be received over the sleeve  44  of the device  30 . The introducer sleeve  60  includes a detented slot  62  for releasably receiving the pin  46  of the device  30 . This enables the introducer  56  to be releasably locked to the device  30  during deployment of the device. It also permits the introducer to be relocked to the device  30  for extracting the device should it be necessary to remove the device  30  for exchange with another device.  
         [0055]    As previously mentioned, the circumflex artery  17  passes under the coronary sinus  14 . When the device  30  is deployed, it should not be permitted to exert a force from the coronary sinus against the circumflex artery. Hence, in accordance with one embodiment of the present invention, the device is implanted within the coronary sinus at a position whereby the distal end  34  of the device  30  is proximal to the crossover point of the circumflex artery and the coronary sinus. This requires determination of the crossover point. FIGS. 5 and 6 illustrate how such a determination may be made in accordance with the present invention.  
         [0056]    A first elongated member, such as an elongated wire or coil wire  70  is inserted into the circumflex artery  17 . The wire  70  may be formed of a material visible under X ray fluoroscopy or be of other material having a coating which is visible under X ray fluoroscopy. Next, a second wire which may be the guide wire  52  is inserted into the coronary sinus  14  by way of the ostium of coronary sinus  13 . Again, the wire  52  is preferably of a material visible under X ray fluoroscopy or of another material having a coating which is visible under X ray fluoroscopy. Preferably, the wires  52  and  70  are elongated coils formed of stainless steel.  
         [0057]    The heart  10  or at least that portion of the heart  10  where the circumflex artery passes under the coronary sinus is subjected to X ray fluoroscopy. X ray fluoroscopy is well known in the art. The crossover point  19  where the wires  52  and  70  cross and hence where the circumflex artery and coronary sinus cross may then be readily observed by X ray fluoroscopic examination. This locates the crossover point  19  which is to be distal to the distal end  34  of the device  30  when the device  30  is positioned within the coronary sinus.  
         [0058]    Once the crossover point  19  has been determined, the device  30  may be deployed. During the deployment of the device, the first wire  70  may be left in the circumflex artery to permit continuous X ray fluoroscopic examination or later X ray fluoroscopic examination to confirm proper device positioning.  
         [0059]    [0059]FIG. 7 shows how the assembly  50  may be used to implant the device  30 . Presumably the guide wire  52  has already been positioned in the coronary sinus  14  to support the determination of the circumflex artery and coronary sinus crossover point as described above. As also described above, wire  70  may also be left in the heart at this time.  
         [0060]    Next, the guide tube  54  is advanced into the heart. The guide tube is advanced over the guide wire  52 . The guide wire hence guides the guide tube  54  into the coronary sinus where the device is to be implanted.  
         [0061]    When the guide tube  54  is positioned in the coronary sinus, the device  30  and introducer  56  are then advanced into the guide tube  54  and over the guide wire  52 . The distal end  58  of the introducer  56  is first releasably locked to the proximal end  36  of the device  30  (FIGS. 3 and 4) by advancing the sleeve  60  of the introducer  56  over the sleeve  44  of the device  30  and inserting the locking pin  46  in the detented locking groove  62 .  
         [0062]    With the distal end of the introducer  56  thus engaged with the proximal end of the device  30 , the device may then be pushed by the introducer  56  into the coronary sinus  14  while being guided by both the guide wire  52  and the guide tube  54 .  
         [0063]    When the device is positioned within the coronary sinus  14  with its distal end proximal to the crossover point  19  and its position is confirmed by X ray fluoroscopy, the introducer may be removed. This is accomplished by turning the introducer to unlock the pin  46  and retracting the introducer from the guide tube. Then, the guide tube  54  may also be retracted leaving the device in place but still on the guide wire  52 . The performance of the device  30  may now be evaluated. If another device of different properties is deemed more appropriate, the device may be readily replaced. Thus is accomplished by reinserting the guide tube over the device, reinserting the introducer, locking the introducer to the device, and removing the device through the guide tube with the introducer. A new device may then be deployed as previously described.  
         [0064]    Once a device is deployed that satisfies the requirements of the procedure, the guide wire  52 , and the wire  70  if still within the heart, may be removed. This leaves the device  30  in its proper position as illustrated in FIG. 8. Here it may be seen that the device  30  partially encircles the mitral valve  12  within the coronary sinus  14  and adjacent to the mitral valve annulus. The distal end  34  of the device  30  is proximal to the crossover point  19 . The proximal end  36  of the device protrudes slightly into the right atrium (not shown) through the ostium of coronary sinus  13 . The sleeve  44  and pin  46  remain should subsequent removal of the device be deemed necessary.  
         [0065]    [0065]FIG. 9 shows another mitral valve therapy device  130  embodying the present invention. As may be noted in FIG. 9, the device is elongated and has an arched configuration to at least partially encircle the mitral valve  12  adjacent to the mitral valve annulus  20  when implanted in the coronary sinus  14 . The device  130  has an unstressed preformed arched radius smaller than the radius of the dilated mitral valve annulus  20  to impart an inward, generally radial force when implanted in the coronary sinus of the heart as shown. This force again returns the mitral valve annulus  20  to its original or substantially original geometry to permit the cusps  16  and  18  to more fully come together for sealing the left atrium during left ventricular contraction.  
         [0066]    The device  130  has a cross sectional dimension to be received by the coronary sinus. It is also preferably formed of a resilient material to permit the device to be straightened and/or bent for being advanced into the coronary sinus. After being positioned within the coronary sinus, the device is permitted to assume its preformed arched configuration to act upon the mitral valve annulus as previously described. To that end, the device may be formed of, for example, Nitinol, a nickel titanium alloy.  
         [0067]    The device  130  has a distal end  134  and a proximal end  136 . Between the distal end  134  and proximal end  136  the device further includes a channel  138  which is aligned with a bore  140  extending through the distal end  134  and a bore  142  extending through the proximal end  136 . The proximal end  136  further includes an integral sleeve  144  which carries a protruding locking pin  146 . Again, the bores  140  and  142  permit the device to be slidingly received by a guide wire during deployment of the device  130 . The guide wire, during deployment, is confined within the channel  138 .  
         [0068]    The device  130  still further includes a bend  50  at its distal end  134 . As will be noted, the distal end  134  extends beyond the crossover point  19  of the circumflex artery  17  and the coronary sinus  14 . However, because of the bend  150 , the device is precluded from exerting constricting pressure on the circumflex artery  17  even though it extends over the crossover point  19 . The device  130  may be implanted using the assembly as previously described.  
         [0069]    [0069]FIG. 10 shows still another mitral valve therapy device  230  embodying the present invention. Like the device  30  of FIG. 2, the device  230  is elongated and has an arched configuration to at least partially encircle the mitral valve  12  adjacent to the mitral valve annulus  20  when implanted in the coronary sinus  14 . The device  230  has an unstressed preformed arched radius smaller than the radius of the dilated mitral valve annulus  20  to impart an inward, generally radial force on the mitral valve annulus  20  when implanted in the coronary sinus of the heart to return the mitral valve annulus  20  to its original or substantially original geometry permitting the cusps of the mitral valve to more fully come together for sealing the left atrium during left ventricular contraction.  
         [0070]    The device  230  has a cross section dimension to be received by the coronary sinus. It is preferably formed of any of the resilient materials previously described.  
         [0071]    The device  230  has a distal end  234  and a proximal end  236 . Between the distal end  234  and proximal end  236  the device further includes a channel  238  which is aligned with a bore  242  extending through the proximal end  236 . The proximal end  236  further includes an integral sleeve  244  which carries a protruding locking pin  246 . The bore  242  permits the device to be slidingly received by the guide wire during deployment of the device  230 . The guide wire, during deployment, is confined within the channel  238 . The assembly  50  of FIGS. 3 and 4 including the guide wire  52 , guide tube  54 , and elongated introducer  56  may be utilized as described for deploying the device  230 . Here, however, only one end of the device need be slidingly received by the guide wire  52  since the device is well confined within the guide tube  54  and the guide wire  52  is confined within the channel  238 .  
         [0072]    As can thus be seen from the foregoing, the present invention provides a new and improved device, assembly and method for treating mitral regurgitation. The device may be employed with only percutaneous techniques. Further, the mitral valve therapy device may be implanted in a manner which avoids the crossover point of the circumflex artery and coronary sinus. Lastly, the effectiveness of the therapy may be immediately deduced during the implant procedure and permits substitution of devices for optimized results.  
         [0073]    While particular embodiments of the present invention have been shown and described, modifications may be made, and it is therefore intended in the appended claims to cover all such changes and modifications which fall within the true spirit and scope of the invention.