Abstract:
Systems and methods for sizing a cardiac assist device to a heart. A bio-compatible material placed as a cardiac assist device over portions of the heart as desired, is sized to fit the exterior contours of the heart by gathering excess material using a reduction ring, draw strings, or a roller. The remaining material of the cardiac assist device may be sutured, clipped, or otherwise anchored to achieve the desired fit of the cardiac assist device to the heart. Subsequent adjustments to increase or decrease the size of the cardiac assist device may be made to accommodate subsequent changes to the size of the heart by re-performing the reduction ring, draw strings, or roller procedure and re-orienting the sutures, clips, or other anchoring techniques to fit the cardiac assist device to the subsequent heart size.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The invention generally relates to systems and methods for sizing a cardiac assist device to fit over portions of a heart. More specifically, the invention relates to systems and methods for sizing a chronic heart failure passive restraint device to fit over portions of a heart, while permitting subsequent adjustments of the device in order to accommodate changes in the size of the heart.  
         [0003]     2. Prior Art  
         [0004]     Heart failure syndrome is a highly debilitating and degenerative disorder resulting from damage to the heart muscle. The damage to the heart muscle may be caused by a number of conditions, including coronary artery disease, long standing hypertension, leaky heart valve(s), and infections.  
         [0005]     Heart failure typically occurs when a weakened heart cannot pump an adequate amount of blood to meet the demands of the body&#39;s other organs and tissues. The defining characteristic in the progression of heart failure is that there is eventually a reduction of the heart&#39;s ability to meet the metabolic needs of the body.  
         [0006]     Whatever the cause or source of damage, the heart&#39;s ability to pump adequate amounts of blood to support the body&#39;s needs is diminished, and the progressive deterioration of cardiac physiology and function occurs. The inadequate supply of oxygen-rich blood often causes people with heart failure to experience shortness of breath and fatigue during even routine daily activities. As the condition progresses, the contraction rate of the heart increases in response to the decreasing cardiac output. As a result, the chambers of the heart, particularly the ventricles of the heart, become increasingly enlarged as the heart tries to compensate for its inefficiencies.  FIGS. 1   a - 1   c  show representative stages of progressive deterioration of a heart, wherein  FIG. 1   a  shows a normal heart H with appropriately sized atrial chambers  1  and  2 , and appropriately sized ventricular chambers  3  and  4 .  FIG. 1   b  shows slightly enlarged ventricular chambers  3  and  4 , and  FIG. 1   c  shows increasingly enlarged ventricular chambers  3  and  4 . Ultimately, a complex process of damaging structural and functional changes to the heart results. Ventricular dilation results in thinning of the ventricular wall, which elevates the wall stress. This increase in wall stress leads to altered gene expression at the cellular level that results in attenuated adrenergic response, impaired myocyte function, cardiomyocyte hypertrophy, altered extracellular matrix production and cell death. This remodeling process continues as the body tries to continually compensate for ineffective pumping and eventually leads to heart failure.  
         [0007]     The disease of heart failure is common, lethal, and expensive to treat. An estimated 5.1 million Americans have heart failure with approximately 500,000 new cases diagnosed each year. In 1999, an estimated $20.3 billion in directs costs were spent for the care of heart failure patients. Heart failure is also the most common cause of hospitalization for patients 65 years and older in the United States. The mortality rate is 50% at five years for patients diagnosed with heart failure, and to date, there are limited treatment alternatives available.  
         [0008]     Certain cardiac disease treatment devices have been proposed to help alleviate the disease of heart failure. For example, U.S. Pat. No. 6,425,856 provides a cardiac constraint device comprised of a jacket made of biologically compatible material.  FIG. 1   d  illustrates how the jacket  20  may be positioned around the heart H to improve cardiac function. The jacket surrounds a valvular annulus of the heart and at least the ventricular lower extremities of the heart. Once positioned as desired around the heart, the jacket  20  is sutured to the heart. A piezoelectric material or separately provided stays with receptacles are then used to decrease the volume of the jacket to fit more closely over the heart.  
         [0009]     The jacket  20  thus works on a passive, mechanical level to reduce periodic myocardial over-stretch and wall stress, and serves as a constant “reminder” to the heart of how the heart should perform. The jacket thus encourages down-regulation of increased local neurohormonal activity, and reduces or eliminates cardiomyocyte maladaptive gene expression. As a result, the jacket may slow or halt the progressive deterioration of the heart and may stimulate reverse remodeling of the heart.  
         [0010]     Suturing the jacket to the heart is a cumbersome procedure however, and the stays are prone to loosening from their receptacles. Even where U-clips or staples have been used in place of sutures, the procedures of fitting the jacket around the heart and placing the U-clips to secure the jacket to the heart the procedure are time-consuming and cumbersome. Further, subsequent adjustments to the jacket, where provided for, may accommodate for decreases in the size of the heart but may not account for increases in the heart size. As a result, precise positioning of the jacket around the heart has proved time consuming and maintaining the jacket closely over the heart over time has been problematic. Further still, positioning and securing the jacket about the heart using endoscopic tools and techniques as the heart is beating has proved challenging.  
         [0011]     An alternative procedure for surrounding a heart with a cardiac assist device endoscopically places and manipulates a bio-compatible mesh sheet wrapping means around the heart as described in co-pending U.S. patent application Ser. No. ______, filed ______, 2004, (Attorney Docket No. 17386) of common assignment herewith, the entire disclosure of which is incorporated herein by reference. The wrapping means is secured directly to the heart by sutures or to anchoring devices separately secured to the heart. This co-pending application however, does not provide the various sizing or subsequent adjustment systems and methods of the present invention as described further hereinbelow.  
         [0012]     In view of the above, a need exists for systems and methods that provide more reliable sizing of a cardiac assist device to fit closely about a heart. A further need exists for systems and methods that permit subsequent adjustments to maintain the cardiac assist device in a close-fitting position around the heart.  
       SUMMARY OF THE INVENTION  
       [0013]     The systems and methods of the invention provide for sizing a cardiac assist device to fit closely adjacent portions of a heart. The cardiac assist device may help reduce distention of chambers of the heart and may encourage remodeling of a damaged or diseased heart. The cardiac assist device is comprised of a bio-compatible material having an open first end with a seam about its periphery and a second end opposite the first end. In some embodiments of the invention, the second end is closed to form a sack-like cardiac assist device into which the heart is placed. In other embodiments of the invention, the second end is open to form a tubular-like cardiac assist device into which the heart is placed.  
         [0014]     According to the systems and methods of the invention, one or more openings, are provided through the chest wall of a being. The cardiac assist device, instruments, and visualization means are inserted into a chest cavity of the being through the one or more openings in order to place, fit and secure the cardiac assist device to the heart. The visualization means may be an endoscope, a fiber optic cable or a camera on an elongate member, for example, permitting a medical professional to view the various procedures performed as they occur according to the invention.  
         [0015]     In practice, once the cardiac assist device is in the chest cavity of the being, the heart is received through the open first end of the cardiac assist device until an apical region of the heart approaches the second end thereof. The first end is then sutured, or otherwise secured, to a base of the heart or to anchoring devices that are secured to the heart, such as those described in co-pending U.S. patent application Serial No. ______, (Attorney Docket No. 17386) the entire disclosure of which has been incorporated herein by reference.  
         [0016]     After securing the first end to the heart, excess material of the cardiac assist device is then gathered to conform the cardiac assist device to the heart. The gathered material is then secured, thereby fitting the cardiac assist device more closely to the heart. When desired, subsequent adjustments to the cardiac assist device may be performed to increase or decrease the size of the cardiac assist device by gathering or releasing the excess material, as appropriate, thereby promoting an ongoing close fit of the cardiac assist device with the heart.  
         [0017]     According to the systems and methods of the invention a material gathering device is used to gather the excess material of the cardiac assist device. One embodiment of the material gathering device comprises drawstrings incorporated into and weaved throughout the bio-compatible material. The drawstrings are endoscopically drawn or released, as needed, and then secured, in order to fit the cardiac assist device closely to the heart. Paired ends of each drawstring are manipulated to secure the drawstrings and cardiac assist device in a desired position around the heart. Each drawstring may be secured, for example, by one of tying, snapping, clipping, zipping, twisting or cable-tying a respective set of paired ends to one another. Subsequent adjustments to the cardiac assist device in order to fit an increased or decreased heart size are readily achieved by unsecuring the drawstrings, re-drawing or releasing the drawstrings to accommodate the changed heart size, and then re-securing the paired ends of each drawstring to fit the cardiac assist device closely to the heart.  
         [0018]     According to another embodiment of the systems and methods described herein, the material gathering device is a separately provided reduction ring. The reduction ring is slid over the material at the second end of the cardiac assist device to gather excess material extending therefrom. The gathered material is then secured to maintain the cardiac assist device closely to the heart. The reduction ring is then removed. Subsequent adjustments to the cardiac assist device in order to accommodate changing heart sizes are readily accomplished by un-securing the gathered material, re-performing the reduction ring procedure, and re-securing the gathered material in a desired position so that the cardiac assist device again fits closely to the heart. In some embodiments the ring at the distal end of a rod is positioned over one end of the cardiac assist device to loosely gather the excess material. In other embodiments, the ring is positioned over on end of the cardiac assist device and a slidable rod is maneuvered to close the ring more snugly around the excess material.  
         [0019]     In yet another embodiment of the systems and methods described herein, an anterior seam is provided on the material of the cardiac assist device. The anterior seam is located between the first end and the second end of the material. The anterior seam is provided with closure devices on either side of the anterior seam. The closure devices are endoscopically aligned with and connected to one another to close the anterior seam of the cardiac assist device. A separately provided adjustment roller attaches to the closed anterior seam and closure devices to gather excess material of the cardiac assist device and fit the device more closely to the heart. The excess material is gathered by rotating the roller in one direction and then securing the gathered material. The adjustment roller is then removed from the chest cavity, or the roller remains in place and a handle of the adjustment roller is detached from the roller and removed from the chest cavity. In either case, the adjustment roller readily provides subsequent adjustments to the cardiac assist device by un-securing the gathered material, re-performing the adjustment roller procedure to gather excess material to accommodate the changed heart size, and re-securing the gathered material.  
         [0020]     Of course, the artisan should readily appreciate that the various material gathering devices and techniques described herein may also be used in combination in order to fit the cardiac assist device even more precisely to the heart.  
         [0021]     The various embodiments of the system and methods of the invention described herein provide several advantages over and solve many of the problems posed by prior known devices and methods of sizing a cardiac assist device to a heart. The various exemplary embodiments of the invention minimize the time and cumbersome efforts previously required to fit and suture a cardiac assist device to the heart. The various exemplary embodiments of the invention also provide increased flexibility in terms of adjusting the cardiac assist device to accommodate increased or decreased sizes in the heart after initial placement of the device over the heart. Further, the various embodiments of the invention simplify the endoscopic placing and securing of the cardiac assist device about the heart even during beating heart procedures and may be used in non-endoscopic, i.e. open chest, or hybrid procedures. Moreover, the various embodiments of the invention described herein promote a more precise fit of the cardiac assist device to the heart, even as remodeling of the heart may occur.  
         [0022]     The above and other features of the invention, including various novel details of construction and combinations of parts, will now be more particularly described with reference to the accompanying drawings and claims. It will be understood that the various exemplary embodiments of the invention described herein are shown by way of illustration only and not as a limitation thereof. The principles and features of this invention may be employed in various alternative embodiments without departing from the scope of the invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0023]     These and other features, aspects, and advantages of the apparatus and methods of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where:  
         [0024]      FIGS. 1   a - c  illustrate progressive states of deterioration of a heart representative of heart failure conditions.  
         [0025]      FIG. 1   d  illustrates a prior art mesh jacket placed around a heart.  
         [0026]      FIG. 2  illustrates a cardiac assist device having drawstrings according to a first embodiment of the invention.  
         [0027]      FIGS. 3   a - 3   f  illustrate various securing means at paired ends of a drawstring according to the cardiac assist device shown in  FIG. 2   
         [0028]      FIG. 4  illustrates the cardiac assist device of  FIG. 2  placed about a heart according to the invention.  
         [0029]      FIGS. 5   a  and  5   b  illustrate alternative cardiac assist devices without drawstrings according to a second embodiment of the invention.  
         [0030]      FIG. 6  illustrates a reduction ring according to the invention.  
         [0031]      FIG. 7  illustrates the cardiac assist device of  FIG. 5  placed about the heart using the reduction ring of  FIG. 6  according to a second embodiment of the invention.  
         [0032]      FIG. 8  illustrates material of the cardiac assist device gathered by the reduction ring of  FIG. 6  according to the invention.  
         [0033]      FIGS. 9   a - 9   c  illustrate another embodiment of a reduction ring according to the invention.  
         [0034]      FIG. 10  illustrates a means of securing the excess material gathered by the reduction ring of  FIG. 6  according to the invention.  
         [0035]      FIG. 11  illustrates a cardiac assist device having an anterior seal with closure devices according to a third embodiment of the invention, wherein the anterior seal is in an open position.  
         [0036]      FIG. 12  illustrates the cardiac assist device of  FIG. 11 , wherein the anterior seal is closed.  
         [0037]      FIG. 13  illustrates the ports and instruments used to place the cardiac assist device of  FIG. 11  with an open anterior seam within the chest cavity of a being.  
         [0038]      FIG. 14  illustrates the ports and instrument used to place the cardiac assist device of  FIG. 11  with a closed anterior seam within the chest cavity of a being.  
         [0039]      FIG. 15   a  illustrates one embodiment of a reduction roller according to the invention.  
         [0040]      FIG. 15   b  illustrates an alternative embodiment of a reduction roller having a detachable shaft according to the invention.  
         [0041]      FIGS. 16   a - 16   c  illustrate various stages of fitting the cardiac assist device of  FIGS. 11-13  to a heart using the reduction roller of  FIG. 15  in accordance with the invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0042]      FIG. 2  illustrates a cardiac assist device  100  according to one embodiment of the the systems and methods of the invention. More specifically  FIG. 2  illustrates an exemplary cardiac assist device  100  that surrounds the heart H. The device  100  is comprised of a sack-like bio-compatible material having an open first end  101  and a closed second end  102  opposite the first end. The first end includes a seam along a periphery of the material. The material comprising the cardiac assist device may be a polymeric, a metal, a plastic, an elastic, or other material, such as Merselene or Prolene mesh, known in the art suitable for surrounding the heart and reducing the propensity of chambers of the heart to distend. The material may be woven or non-woven, and does not have to be meshed.  
         [0043]      FIG. 2  further illustrates drawstrings  104  (shown in dashed lines) incorporated into and weaved through the material of the cardiac assist device. The artisan should appreciate that the drawstrings could instead be disposed in a pocket formed in the material of the cardiac assist device. The drawstrings  104  are used as a material management means, for example, to gather excess material and secure the cardiac assist device to the heart in a desired position about the heart, as discussed in greater detail below with respect to  FIG. 4 .  
         [0044]     The drawstrings  104  can be comprised of suture-like material, such as, for example, Merselene, Prolene, stainless steel, c-flex, or other suitable material known in the art. The skilled artisan should appreciate that any number of drawstrings may be used, although three drawstrings are shown in  FIG. 2  for illustrative purposes. Likewise, the artisan should appreciate that the placement and orientation of the drawstrings may vary from that shown in  FIG. 2 , such that more vertically angled drawstrings, or other orientations, may be used in place of, or in combination with, the generally horizontally parallel oriented drawstrings of the cardiac assist device shown in  FIG. 2 . Each drawstring  104  includes a pair of ends  105 ,  106  which extend from the material of the device  100 . Each pair of ends provides a means of tensioning the drawstrings to gather the excess material of the cardiac assist device. Each pair of ends further provides a means of securing the drawstring in place once the desired fit of the cardiac assist device adjacent to the heart is achieved.  
         [0045]      FIGS. 3   a - 3   e  illustrate various alternatives for the pair of ends  105 ,  106  used for securing the drawstrings  104  to one another. For example,  FIG. 3   a  illustrates ends  105 ,  106  that are tied to one another forming a knot (a) to secure the drawstring as desired.  FIG. 3   b  illustrates ends  105 ,  106  having snaps (b) that are snapped together to secure the drawstrings to one another.  FIG. 3   c  illustrates ends  105 ,  106  having teeth (c) that are zipped to secure the drawstrings to one another.  FIG. 3   d  illustrates ends  105 ,  106  that are twisted (d) to secure the drawstrings to one another.  FIG. 3   e  illustrates ends  105 ,  106  having protrusions (e 1 ) and an opening (e 2 ) that are interlocked to cable-tie and secure the drawstrings to one another.  FIG. 3   f  illustrates ends  105 ,  106  that are clipped to secure the drawstrings to one another. The clip may be a sliding clip (f) that opens and closes via hinge (g) to position and secure the clip (f) at a desired position along the drawstrings. An open position of clip (f) is shown in dashed lines in  FIG. 3   f.  The respective paired ends  105 ,  106  of drawstrings  104  thus pose a relatively simple method of securing the drawstrings to one another once tensioned to fit the cardiac assist device closely to the heart.  
         [0046]     In practice, as illustrated in  FIG. 4 , one or more openings, such as a plurality of ports  200 - 202 , are provided through the chest wall C. The ports  200 - 202 , or other openings, are provided in a conventional manner known in the art and permit access to the chest cavity of a patient or subject. For example, trocar tubes may be used for one or more of the ports  200 - 202 . Alternatively, the one or more openings can be an opening within the chest wall or below the chest wall (subyxphoid). In either case, the opening may be held open with tape or other known retraction device. A visualizing means, such as an endoscope  300 , a fiber-optic cable or a camera on an elongated member, is placed into the chest cavity through one of the openings or ports  200 - 202 , and preferably through the lowest port  200 . The endoscope, for example, permits a medical professional to view devices and instruments placed in the chest cavity and medical procedures as they occur in the chest cavity. A monitor  301 , for example, external to the patient or subject connects to the endoscope  300  and provides views of the devices, instruments and procedures on the interior of the chest cavity.  
         [0047]     The cardiac assist device  100  is placed in the chest cavity through one of the openings or ports, and preferably through one of upper ports  201 ,  202 . In this manner, conventional instruments  400 , such as graspers, inserted through a respective upper port  201 ,  202  are able to grasp and manipulate the cardiac assist device to a desired position about the heart. Each of instruments  400  can have grasping elements  401  at a distal end thereof, whereas proximal ends of each instrument  400  extend external to the chest cavity for manipulation of the instrument  400  and activation of the grasping elements  401  by the medical professional. The manipulation and activation of the instruments and grasping elements is done under observation using the endoscope  300 , or other visualizing means, according to the invention.  
         [0048]     After the cardiac assist device  100  is placed in the chest cavity, the instruments  400  grasp the first end  101  of the cardiac assist device and pull the device over the heart until the apex, or apical region, A of the heart approaches the second end  102  of the device. Thereafter, the cardiac assist device is conformed to the shape of the heart and secured to the heart by tensioning the drawstrings  104  and securing the paired ends  105 ,  106  of each drawstring, respectively, to one another. The manipulation of the drawstrings and paired ends thereof are also done using the instruments  400 , or other grasping device known in the art.  
         [0049]     If desired, the cardiac assist device may be further secured directly or indirectly to the heart by sutures, U-clips, staples, adhesives or other securing means, including the anchoring devices of co-pending U.S. patent application Ser. No. ______, (Attorney Docket No. 17386) referenced above. The instruments  400  may be used to perform the suturing, for example, or to otherwise secure the cardiac assist device to the heart or anchoring device. Where anchoring devices, such as those in co-pending U.S. patent application Ser. No. ______, (Attorney Docket No. 17386) are used, and the cardiac assist device is secured to the anchoring devices, it may be preferable to place the anchoring devices on the heart, using instruments  400 , prior to placing the cardiac assist device over the heart. In this manner, the cardiac assist device can be simply and quickly secured to the anchoring devices once the cardiac assist device is positioned as desired adjacent the heart.  
         [0050]     Once the cardiac assist device is in place about the heart as desired, the proximal ends of the instruments  400  are manipulated by the medical professional to grasp and pull, or release, the drawstrings  104  in order to conform the material of the cardiac assist device closely to the heart. The instruments  400  are then further manipulated to tie, or otherwise secure, the drawstrings in order to maintain the cardiac assist device in close conformity with the heart.  
         [0051]     The relatively simple securing devices and methods used according to this embodiment of the invention, permits subsequent adjustments of the cardiac assist device  100  to be readily achieved in a minimally invasive manner after cardiac function has been evaluated. Such adjustments could be done endoscopically, for example, or non-endoscopically, after the patient has stabilized from the initial surgery and placement of the cardiac assist device. Such adjustments could be achieved, for example, using similar openings and instruments as discussed above with respect to the initial placement of the device. The subsequent adjustment would be achieved, for example, using instruments  400  to un-secure the drawstrings and pull, or release, the drawstrings to accommodate the adjusted heart size. Instruments  400  would then be manipulated, as before, to secure the drawstrings to accommodate the changed heart size. Such subsequent adjustments may help eliminate the plateau effect some patients experience after initial placement of the cardiac assist device.  
         [0052]     Because relatively few surgical instruments are required to place and secure the exemplary cardiac assist device of  FIG. 2  over the heart, the medical professional is better able to fit the cardiac assist device to the heart in an uncluttered surgical atmosphere. At the same time, the medical professional is able to view the procedures of placing and securing the cardiac assist device to the heart resulting in easier and more precise sizing of the cardiac assist device to the heart even as the heart beats. As a result, smaller ventricular volume and a more pointed apex of the heart is more likely to be achieved due to the systems and methods herein described.  
         [0053]      FIGS. 5   a - 10  illustrate another embodiment of systems and methods for sizing a cardiac assist device to a heart, wherein like numerals are used to refer to like components. The cardiac assist device  100  in  FIGS. 5   a  and  5   b  generally corresponds to the device  100  shown in  FIG. 2  except that the drawstrings  104  of  FIG. 2  are omitted in the device  100  of  FIGS. 5   a  and  5   b.  Like that of  FIG. 2 , the cardiac assist device  100  of  FIG. 5  is comprised of similar material having an open first end  101  having a seam along the periphery thereof, and a second end  102  opposite the first end. The material is as described above with reference to  FIG. 2 . The second end  102  may be closed to form a sack-like cardiac assist device as in  FIG. 5   a,  or may be open to form a tubular-like cardiac assist device as in  FIG. 5   b.    
         [0054]      FIG. 6  illustrates one embodiment of a reduction ring instrument  500  used, as a material management means, to gather excess material of the cardiac assist device  100  of either of  FIGS. 5   a  and  5   b  after the device  100  has been placed about the heart of a patient or subject. The reduction ring instrument is comprised of a ring  501  at a distal end of the reduction ring instrument  500 , a shaft  502  extending from the ring  501 , and a rod  503  extending from the shaft  502 . The rod  503  comprises a proximal portion of the reduction ring instrument that can be manipulated by the medical professional during endoscopic procedures, for example.  
         [0055]     The ring  501  is comprised of soft compliant material, such as C-Flex, for example, or other material rendering the open loop  501   a  of the ring  501  adjustable to tighten around excess material of the cardiac assist device. The shaft  502  is comprised of a malleable material, such as a malleable  316  stainless steel permitting the ring  501  to be placed at various angles as desired, and the rod  503  is comprised of a rigid material. The shaft  502  should be sufficiently malleable to allow re-shaping or re-orienting of the ring during endoscopic procedures.  
         [0056]     Referring now to  FIG. 7  wherein the sack-like cardiac assist device  100  of  FIG. 5   a  is shown by way of illustration, though similar procedures as described herein are understood to apply equally to the tubular-like cardiac assist device of  FIG. 5   b  as well. In  FIG. 7 , for example, the cardiac assist device  100  is placed into the chest cavity of a patient or subject through one of the openings or plurality of ports  200 - 201  extending through the chest wall C, in conventional manner and similar to that described with reference to  FIG. 4  above. Instruments  400  are likewise inserted into the chest cavity, preferably through upper openings or ports  201 ,  202 . Although not shown in  FIG. 7 , a visualizing means such as endoscope  300  ( FIG. 4 ) is inserted through lower port  200 , for example, enabling the medical professional to view the devices, instruments and procedures in the chest cavity as they occur. As before the visualization means may also be a fiber optic cable or camera on an elongate member. Proximal portions of the instruments  400  and endoscope  300  extend externally from the chest cavity and are available to the medical professional for manipulation as the various procedures occur in the chest cavity.  
         [0057]     The instruments  400  are used to grasp and manipulate the cardiac assist device  100  over the heart H until an apical region A of the heart approaches the second end  102  of the cardiac assist device. Thereafter, the first end  101  of the cardiac assist device is secured directly or indirectly to the base of the heart using sutures, u-clips, staples, adhesives or other securing devices such as anchoring device as disclosed in co-pending U.S. patent application Ser. No. ______, (Attorney Docket No. 17386) referenced above.  
         [0058]     The endoscope  300 , or other visualizing means, is then preferably transferred to one of upper ports  201 ,  202  and the reduction ring instrument  500  is inserted into the port  200  vacated by the endoscope. The instruments  400  may remain in the openings or ports  201 ,  202  even as the endoscope is inserted therein. Of course, either or both of the instruments  400  may be removed from the openings or ports  201 ,  202  at the discretion of the medical professional until needed again. The reduction ring instrument  500  is then manipulated to gather excess material within an opening  501   a  at the closed end  102  of the cardiac assist device near the apical region of the heart.  
         [0059]      FIG. 8  illustrates a view of excess material gathered at the second end  102  of a cardiac assist device  100  according to the systems and methods of the invention. In the embodiment shown in  FIG. 8 , the ring  501  of the reduction ring instrument is shown surrounding the excess material of a tubular-like cardiac assist device  100 , for example.  
         [0060]      FIGS. 9   a - c  shows another embodiment of the reduction ring  1500  comprised of a ring  1501  protruding from a distal end of a hollow slidable rod  1503 . The ring  1501  is comprised of a bio-compatible, suture-like material, for example, as known in the art. Free ends  1502  of the material extend through a proximal end of the slidable rod  1503 . The ring  1501  is placed around excess material at one end of the cardiac assist device as described with reference to  FIGS. 7 and 8 . Thereafter, as shown in  FIGS. 9   b - c,  the slidable rod  1503  is moved towards the ring (arrows x) rendering the ring smaller to more snugly fit around the excess material gathered therein.  
         [0061]     As shown in  FIG. 10 , the gathered material using either embodiments of the reduction ring, is then either secured by known securing means, such as clips  510 , or other securing means known in the art, such as sutures, in order to maintain the cardiac assist device in close conformity to the heart. Some or all of the excess material extending beyond the clips  510 , for example, may be removed at the discretion of the medical professional, such as with endoscopic cutting instruments known in the art. Retaining some of the excess material beyond the clip permits greater flexibility to accommodate future increases in the heart size subsequent to the initial placement of the cardiac assist device.  
         [0062]     Subsequent adjustments to the cardiac assist device using the reduction ring techniques and devices described above are readily available to accommodate changing heart sizes. Where a decreased heart size occurs, for example, the reduction ring  501  or  1501  is simply re-applied to gather any additional excess material. The securing means, or clips  510 , are then re-positioned to accommodate the new heart size. Where an increased heart size occurs, then the clips  510  are removed to free the excess material, the reduction ring is re-applied to gather any new amount of excess material, and the clips  510  are re-applied to accommodate the increased heart size. If the securing means is re-usable, i.e., can be opened and closed, then the same securing means can simply be slid towards or away from the heart in order to adjust for decreased or increased heart sizes, respectively.  
         [0063]     As in the exemplary embodiments described above with reference to  FIGS. 2-4 , the embodiments of the reduction ring systems and methods described with reference to  FIGS. 5   a - 10  provide relatively easy sizing of the cardiac assist device in an uncluttered operating space. Re-shaping of the heart resulting in the preferred more pointed apex of the heart is thus more readily promoted. Further, the initial placement and subsequent adjustment procedures, if desired, may be performed endoscopically, or non-endoscopically, as well.  
         [0064]      FIGS. 11-14   c  illustrate a third exemplary embodiment of the cardiac assist device according to the systems and methods of the invention. Similar to the earlier described cardiac assist devices, the cardiac assist device  1000  shown in  FIG. 11 , for example, is also comprised of a bio-compatible material. As before, the material is as described above with reference to  FIG. 2 .  
         [0065]     As shown in  FIG. 11 , the cardiac assist device  1000  is pouch-shaped and oversized relative to the heart H. The pouch-shaped device has an open first end  1001  with a seam along the periphery thereof, and a closed second end  1002 , the second end being opposite the first end. When placed around the heart H, the closed second end surrounds an apical region A of the heart, and the first end is secured to a base of the heart. As in other embodiments of the invention described above, securing means  1003 , such as sutures, clips, staples, adhesives, drawstrings as described herein, magnets, anchoring devices as described in co-pending U.S. patent application Ser. No. ______, (Attorney Docket No. 17386), or other securing means known in the art are used to secure the first end of the cardiac assist device directly or indirectly to the heart initially.  
         [0066]     Referring still to  FIG. 11 , the cardiac assist device further comprises an anterior seam  1010  extending between the first end  1001  and second end  1002  of the device. More specifically, the anterior seam  1010 , shown open in  FIG. 11 , extends from the first end  1001  towards, but not as far as, the second end  1002  of the cardiac assist device. Closure devices and corresponding receiving members  1011 ,  1012  are placed on either side of the anterior seam  1010 . The closure devices and receiving members  1011 ,  1012  may be snaps, buttons, magnets, or other fastening means known in the art.  
         [0067]      FIG. 12  illustrates the closure devices  1011 ,  1012  connected to one another in order to close the anterior seam. The anterior seam is generally closed once the cardiac assist device has been placed adjacent the heart in a desired position.  
         [0068]     In practice, with reference first to  FIG. 13  and  FIG. 14 , a plurality of ports  1200 - 1202 , or other openings, are provided through the chest wall C. As in the earlier described embodiments, the ports  1200 - 1202 , or other openings, are provided in a conventional manner known in the art and permit access to the chest cavity of a patient or subject. The openings may alternatively be an opening within the chest wall or below the chest wall (subyxphoid) of the patient. In either case the opening may be held open using tape or other retraction device. A visualizing means  1300 , such as an endoscope, a fiberoptic cable, or camera on an elongate member, is placed into the chest cavity through one of the openings or ports, and preferably initially through the lower opening or port  1200 . The cardiac assist device  1000  is placed into the chest cavity through one of the remaining openings or ports  1201 ,  1202 , for example.  
         [0069]     Conventional instruments  1400  are inserted into the chest cavity through the openings or ports  1201 ,  1202 . Similar to the instruments  400  in earlier embodiments, each instrument  1400  has grasping elements  1401  at a distal end thereof. Each instrument  1401  also has a proximal end extending external to the chest cavity. The visualizing means  1300  likewise has a proximal end extending externally from the chest wall. In this manner, the proximal ends of visualizing means  1300  and instruments  1400  are available for manipulation by a medical professional. At the same time, the visualizing means  1300  permits the medical professional to observe the various devices, instruments and procedures within the chest cavity as they occur.  
         [0070]     After initially placing the cardiac assist device  1000  into the chest cavity through one of the openings or ports, the anterior seam  1010  of the cardiac assist device is open, as shown in  FIG. 13 . The instruments  1400  then grasp the first end of the cardiac assist device  1000  and maneuver the cardiac assist device to a desired position around the heart. Thereafter, as shown in  FIG. 14 , the instruments  1400  are further manipulated to close the anterior seam  1010  by aligning and securing the closure devices  1011  on one side of the anterior seam with the closure devices  1012  on the other side of the anterior seam. In this manner, the cardiac assist device loosely surrounds the heart but does not reduce ventricular volume.  
         [0071]      FIG. 15   a  shows a reduction roller  1020 , as a material management means, that releasably attaches to the closed anterior seam and closure devices. The roller  1020  in  FIG. 15   a  includes a distal end  1021  having attachment means  1022 , and a proximal end  1023  including a handle or shaft  1024 . The attachment means  1022  in  FIG. 15   a  a are sockets, for example, that fit over the exposed heads of closure devices  1011 ,  1012  when the anterior seam is closed. The attachment means  1022  in  FIG. 15   a  could instead be magnets, Velcro, or other attachment means known in the art that would similarly connect to the heads of closure devices  1011 ,  1012  when the anterior seam is closed. The reduction roller is preferably thin and composed of metal, or other strong, bio-compatible polymer. The shaft  1024  is stainless steel.  
         [0072]      FIG. 15   b  shows an alternative reduction roller  1020 , as a material management means, having a handle  1024  that detaches from the distal end  1021  of the roller via coupling  1025 .  FIG. 15   b  further shows an alternative attachment means  1022  comprised of rails, for example, that slide over the closed anterior seam to connect to the cardiac assist device. The attachment means  1022  may thus comprise sockets, rails, magnets, or other attachment means known in the art suitable to attach to the closure devices and anterior seam of the cardiac assist device.  
         [0073]     In practice, the reduction roller  1020  is inserted into the chest cavity of a being through any one of the openings or ports  1200 - 1202  as described above with reference to  FIGS. 13 and 14 , even as the instruments  1400  or visualizing means  1300  continue to reside in the openings or ports. Of course, the instruments  1400  or visualizing means  1300  may be repositioned or removed from any of the openings or ports in order to better accommodate the reduction roller in the discretion of the medical professional.  
         [0074]      FIGS. 16   a - 16   c,  wherein the chest wall, ports, instruments and visualizing means are omitted from illustration but understood to exist as shown and described earlier with respect to  FIGS. 11-15   b,  show various stages of fitting the cardiac assist device  1000  to the heart using the reduction roller of  FIG. 15   a,  for example. More specifically,  FIG. 16   a  shows the attachment means  1022  of the roller  1020  grasping, or otherwise releasably attached to, the closure devices  1011 ,  1012  and closed anterior seam  1010 .  FIG. 16   b  then shows the roller  1020  lifted by the medical professional to pull the excess material of the cardiac assist device  1000  to a more taut position. Referring still to  FIG. 16   b,  the roller  1020  is then rotated to wrap the excess material around the roller. As a result, as shown in  FIG. 16   c,  the material of the cardiac assist device fits closely to the contours of the heart. The excess material gathered on the roller is then secured with sutures, clips, staples, or other suitable anchoring devices as in earlier described embodiments including those in co-pending U.S. patent application Ser. No. ______, (Attorney Docket No. 17386). The roller  1020  is then pulled out from the gathered material, or left in place while the shaft  1022  is released from the roller. The artisan should appreciate that were the reduction roller of  FIG. 15   b  used instead, the handle  1024  could simply be removed by uncoupling the handle  1024  from the attachment means  1022  of the roller using coupling  1025 . In this maner, the distal end  1021  of the roller would remain with the cardiac assist device as it is secured in place about the heart.  
         [0075]     If necessary, additional sizing of the cardiac assist device at the apical region of the heart may be accomplished using the reduction ring technique described above. Alternatively, if additional sizing of the device at the apical region of the heart is necessary, the drawstring technique described above can be used to tighten and more precisely fit the device to the apex of the heart. In this latter case, the pouch shaped cardiac assist device would be provided with at least one drawstring near the apical region of the heart.  
         [0076]     Subsequent adjustments to the cardiac assist device using the roller technique are readily available to accommodate changing heart sizes. Where either a decreased or increased heart size occurs, the gathered material is unsecured and unraveled, the roller with the handle is re-applied to the closed anterior seam, and the roller is rotated to gather any additional excess material. The gathered material is then re-secured at the new position in order to accommodate the new heart size. As before, the roller is then either removed, or the handle only is removed, and the gathered material is secured in a desired position about the heart. If desired, the reduction ring or drawstring techniques may also be used to even more precisely fit the apical region of the heart to the cardiac assist device, as discussed above.  
         [0077]     As in the exemplary embodiments described above with reference to  FIGS. 2-10 , the exemplary embodiments described with reference to  FIGS. 11-16   c,  the reduction roller systems and methods provide relatively easy sizing of the cardiac assist device in a relatively uncluttered operating space. Re-shaping of the heart resulting in the preferred more pointed apex of the heart is thus more easily promoted. The initial placement and adjustments of the cardiac assist device may be performed endoscopically or non-endoscopically as well.  
         [0078]     The various exemplary embodiments of the invention as described hereinabove do not limit different embodiments of the present invention. The bio-compatible material, described herein as an exemplary cardiac assist device, is not limited to the materials, designs, or shapes referenced herein for illustrative purposes only, and may comprise various other materials, designs or shapes suitable for the procedures described herein as should be appreciated by one of ordinary skill in the art. For example, the material may be a fabric like that described in U.S. Pat. No. 6,682,476 or materials such as those described in U.S. Pat. No. 6,595,912, which are incorporated herein by reference.  
         [0079]     While there has been shown and described what is considered to be preferred embodiments of the invention, it will, of course, be understood that various modifications and changes in form or detail could readily be made without departing from the spirit or scope of the invention. For example, while the invention has been described with reference to an endoscopic procedure, the system described herein can also be used in non-endoscopic, open chest or hybrid procedures that would not rely solely upon openings in a patient&#39;s chest. It is therefore intended that the invention be not limited to the exact forms described and illustrated herein, but should be constructed to cover all modifications that may fall within the scope of the appended claims.