Abstract:
A prosthetic heart valve reinforcement ring is disclosed. The prosthetic includes an outer ring sized and dimensioned to fit around an annulus of a heart valve and an inner ring configured and arranged to couple to the outer ring. The inner ring and the outer ring have complimentary mating formations configured and arranged to grip sutures therebetween. A method of reinforcing heart valve is also disclosed. Sutures are provided around an annulus of a heart valve. The sutures are corralled within an outer sizing ring. The outer sizing ring is placed around the annulus of the heart valve. An inner sizing ring is inserted within the outer ring, locking the sutures. The sutures are adjusted and the heart valve is tested for a proper fit. The outer sizing ring is removed and a prosthetic ring is placed over the inner sizing ring, locking the sutures. The sutures are tied.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent document claims priority to earlier filed U.S. Provisional Patent Application Ser. No. 61/639,482, filed Apr. 27, 2012, and U.S. Provisional Patent Application Ser. No. 61/641,338, filed May 2, 2012, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present patent document relates generally to heart valve ring and aortic root remodeling procedures, and more specifically to a prosthetic device for reinforcement of heart valves (mitral, tricuspid, aortic, pulmonic) and also for aortic root remodeling. With reference to the aortic root, the concept of sizing applies to not only the annulus, but also to the aortic root structure itself, both in terms of “ring” sizing, as well as, “graft” sizing (e.g. in Tirone David type procedures). 
     2. Background of the Related Art 
     Heart valve reinforcement rings (also, aortic root remodeling grafts) are difficult to size properly and, once sized properly, require additional labor to secure into position to the heart structure being reinforced or remodeled, as the case may be. This process can become technically even more difficult (more labor intensive) during minimally invasive procedures where the surgeon must implant the ring through a small incision under circumstances where even easy steps potentially become more difficult. 
     Therefore, there is a perceived need in the industry for heart valve annular rings (aortic root grafts) that are easier for a surgeon to secure into position especially in terms of proper sizing, ease of implantation, and minimization of surgical steps/operating time. These concepts may become even more relevant to patients undergoing minimally invasive procedures. 
     SUMMARY 
     The present invention solves the problems of the prior art by providing a heart valve ring (aortic root graft/composite ring with graft) that can be implanted with greater ease and accuracy. The ring includes an inner ring and an outer ring that snap together. Sutures are captured between the rings to allow the surgeon to test the fit of the ring. Once sure of the fit, the ring may be (permanently) secured into position in one of several ways. (Also the valve/root structures can be measured using disposable/reusable sizers, then swaped-out for the final prosthetic device to be permanently implanted). The ring may further include a composite graft, or simple graft, extending from the outer ring for aortic root remodeling procedures. Furthermore, the ring may be used with self-cinching or self-securing sutures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description, appended claims, and accompanying drawings where: 
         FIG. 1A  shows a step of an outer portion of a sizing ring corralling the sutures around heart valve; 
         FIG. 1B  shows a step of an inner portion of a sizing ring being inserted into the outer ring, trapping the sutures therebetween; 
         FIG. 1C  shows a step of a prosthetic ring being substituted for the outer ring, with sutures being progressively tied to the prosthetic ring; 
         FIG. 1D  shows a step of removing the inner sizing ring from the outer prosthetic ring; 
         FIG. 2A  shows a partial top view of a first embodiment of a suture engaging features of the prosthetic ring; 
         FIG. 2B  shows a partial top view of a second embodiment of a suture engaging features of the prosthetic ring; 
         FIG. 2C  is a cross-section view through line  2 C- 2 C of  FIG. 2A ; 
         FIG. 2D  is a cross-section view through line  2 D- 2 D of  FIG. 2B ; 
         FIG. 3  shows a method of tying both the prosthetic and inner sizing ring to the surgical site; 
         FIG. 4  shows a partial view of a third embodiment of suture engaging features on both the prosthetic ring and the inner sizing ring; 
         FIG. 5  shows a method of tying both the prosthetic and inner sizing ring to the sutures using a suture with a pre-tied clasp; 
         FIG. 6A  shows a partial view another embodiment of the prosthetic having an outer ring and an inner ring, where only the inner ring includes suture engaging features; 
         FIG. 6B  shows a partial view of the inner ring shown in  FIG. 6A  in isolation; 
         FIG. 7  shows a partial view of another embodiment where the prosthetic includes grooves coated with a soft suture-gripping material; 
         FIG. 8  shows a partial view of another embodiment of a prosthetic ring that includes a mesh sheath that the surgeon may sew directly to the surgical site; 
         FIG. 9A  shows an exploded partial view of an embodiment of a prosthetic ring with graft material extending therefrom; 
         FIG. 9B  is a partial view of an embodiment of the prosthetic with graft material that locks inside an outer ring; 
         FIG. 9C  is a partial view showing the outer ring being removed from the prosthetic ring with graft material; 
         FIG. 9D  is a partial view showing the prosthetic ring being tied in place at the surgical site; 
         FIG. 10A  is a partial exploded view of an embodiment of the prosthetic ring with graft material that snaps around or over an inner ring; 
         FIG. 10B  is a bottom view of the embodiment shown in  FIG. 10A , showing the outer ring locking around the inner ring; 
         FIG. 11  is an exploded view of an embodiment of a prosthetic ring for aortic root remodeling procedures showing the peaks and valleys in the prosthetic ring; 
         FIG. 12  is a perspective view of an embodiment of the prosthetic ring for aortic root remodeling procedures showing the sutures grasped in the prosthetic ring; 
         FIG. 13  is an elevation view of an embodiment of the prosthetic ring for aortic root remodeling procedures showing graft material extending from the prosthetic ring; 
         FIG. 14  is a view of a single ring system, prosthetic heart valve ring, showing a plurality of groove with suture gripping material; and 
         FIG. 15  is an enlarged view of inset  15  of  FIG. 14 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Provisional Patent Application Ser. Nos. 61/551,728, filed on Oct. 26, 2011, and 61/555,002, filed on Nov. 3, 2011, are incorporated herein by reference in their entirety. 
     The “sizing” component of the operation can be performed using a full set of separate sizers which can be reusable or disposable, such as is commonly the practice today for ring/valve surgery. Once the proper size has been determined (using the previously described sizing system), the actual prosthetic device can then be substituted and used for implantation. This type of system may have the added benefit of allowing for the final prosthesis to be constructed as a solid ring (no gap at 12 o&#39;clock as seen in some figures of the sketches). Alternatively, the prosthesis itself can be used for both sizing and final implantation. 
     Though, the initial portion of the procedure involves two rings, the final prosthetic implant can either be the described combination of two rings, or alternatively, a single remaining ring, after one of the two rings is removed. This will depend on the method by which the prosthesis is secured into position. 
     The preferred embodiment results in the final implantation of only one of the two, paired rings. With this embodiment, the two ring system can be utilized such that the inner (inner or outer for aortic root) ring is a temporary guide used to help align and position sutures but is then removed after the sutures have been tied down onto the outer permanent ring (see, e.g.,  FIGS. 1D, 10C ). Additional benefits to the one ring method include less prosthetic material. Also potential for infectious complications can be minimized because less or better material can be used (such as a plain metal ring instead of one covered with mesh to accept sutures). 
     Referring to  FIGS. 1A-1D  of the sketches demonstrates a quick summary of the process.  1 A) Outer ring  10  of the sizing device is placed outside of the annular sutures  12 .  1 B) The inner ring  14  of the sizing device is combined with the outer ring  10 , and the annular sutures  14  are captured in between. This combination can be repeated several times until the best size and shape have been selected.  1 C) The outer sizing ring  10  is removed and replaced with the actual prosthetic device  16 . The inner ring  14  can remain in place to help with retaining suture position and tying. Sutures  12  are tied down directly onto the prosthetic ring at  18 .  1 D) The inner ring  14  is removed, leaving the prosthetic ring  16  in place. 
     As will be more fully explained below, the sutures  12  can be tied without the use of additional needle passes by simply tying the “rings together.” This is accomplished by “hooking” or “wrapping” the sutures  12  on elements of the prosthetic ring  16  such as barbs, posts, or some other form of either a groove or projection, etc., described in more detail below. 
       FIG. 2A  shows spaced apart grooves  20  on the outer ring  16  of the prosthetic. In a cross-section view,  FIG. 2C , the space between the grooves  20  includes a hook  22  formed within the body of the outer prosthetic ring  16 . That is, a small recess  24  within the body of the outer ring  16  of the prosthetic is formed, creating a hooked end  26 . The sutures  12  are tied off on the hook  22 , preventing the outer ring  16  from moving on the annulus. 
       FIG. 2B  shows an embodiment of the outer ring  116  where the outer ring  116  includes closely spaced grooves  120 . The surfaces of the grooves may include a rubber coating to grip sutures. In a cross-section view,  FIG. 2D , the space between the grooves  120  includes a hook  122  formed from a projection from the body of the outer ring  116 . The sutures  12  are tied off on the hook  120 , preventing the outer ring  116  from moving on the annulus. 
     One of various knot-tying devices can be used to tie, crimp, etc. the sutures  12  as is often done with minimally invasive surgical techniques. 
     Referring to  FIG. 3 , in a two-ring system, the prosthetic ring  200  includes an inner ring  214  with a gap  228 , or defect, allowing sutures  12  to be gathered within the inner ring  214 . The gap  228  also permits the inner ring  214  to flex inwardly. The inner ring  214  snap-fits into an outer ring  216 . Together, the inner ring  214  and outer ring  216  may form a complete prosthesis. The inner ring  214  and outer ring  216  may include complimentary mating formations to permit a tight and secure fit together, yet permit the sutures  12  to be captured between the inner ring  214  and the outer ring  216 . More specifically, the inner ring  214  may include a concave surface that complimentarily mates with a convex surface on the outer ring  216 . The entire prosthesis  200  may then be tied down in place as is known in the art. 
     Because the embodiment includes an inner ring  214  and an outer ring  216  that can snap-fit around the sutures  12 , the surgeon can determine an optimal fit for the prosthetic ring  200  prior to tying the prosthetic ring  200  in place around the annulus of the heart valve. The prosthetic ring  200  thus doubles as a sizer for determining the appropriate ring size for reinforcing the heart valve and then as the permanent prosthetic. The surgeon need not remove the prosthetic ring  200  once he has determined the fit is adequate. This prosthetic ring  200  may be used for any heart valve including aortic root remodeling procedures as well. 
     The inner ring  214  and the outer ring  216  may also include notches or stays  218  formed on the surface facing away from the mating surfaces of either ring (See, e.g.  FIG. 4 ). These notches or stays  218  are configured to receive the suture  12  therein or tied thereto, respectively, and prevent the prosthetic ring  200  from shifting. Alternatively, a suture  12  with a self-tying knot and clasp  220  may be used to secure the assembled prosthetic ring  200  to the annulus  222  of the heart valve. (See, e.g.,  FIG. 5 ). Also, a suture tying hand tool may be used such as known in the art. 
     Referring to  FIGS. 6A and 6B , in another embodiment  300  of a two-ring system, the grooves  320  may be formed on the inner ring  314  instead of the outer ring  316 . The inner ring  314  may also have a complimentary profile to the outer ring  316  thereby minimizing the overall size of the two rings  314 ,  316  when interlocked. More specifically, the inner ring  314  includes a concave outer surface  330  that complimentarily mates with a convex inner surface  332  of the outer ring  316 . The grooves  320  formed on the inner ring  314  form tooth-like projections that the sutures  12  are tied down against. Additional sutures  12  may be wrapped around both rings  314 ,  316 , securing the entire embodiment  300  to the annulus of the heart valve. The inner ring  314  may also include hooks and tie-down structures for the sutures  12  as described in  FIGS. 2A, 2B and 4 , and accompanying text. 
     Referring to  FIG. 7 , in another embodiment  400 , the grooves  420  on the outer prosthetic ring  416  may include a gripping material  422 , such as a rubber coating, formed inside the grooves  420 . The gripping material  422  allows the sutures  12  to be pulled into and out of the grooves  420  without fear of damage and to enable positioning and testing of the prosthetic ring  416 . Once the fit is determined to be optimal, the sutures  12  may be tied down against the outer ring  416  as described previously. As may be appreciated by one skilled in the art, gripping material  422  may also be added to grooves  420  formed on an inner ring  320 , as shown in  FIGS. 6A and 6B , if used. 
     Referring to  FIG. 8 , in another embodiment  500 , the prosthetic ring  516  may also be sheathed in a mesh material  534 , enabling a surgeon to sew the prosthetic ring  516  directly to the annulus. The mesh material  534  provides an additional method of anchoring the prosthetic ring  516  to the annulus where grooves and other tie-down structures described above, prove to be inadequate to create the fit the surgeon desires. By sewing through the mesh material  534 , the surgeon may further secure the prosthetic ring  516  to achieve the most optimal fit. 
     Referring to  FIGS. 9A-9D, 10A, 10B, and 11-13 , similar concepts can be applied to remodeling of the aortic root of the heart. Various applications include, but are not limited to, annular reinforcement using a ring system, using a graft system, or a composite ring/graft system. Which can also be secured in a variety of ways as previously described, but in addition, a technique can be utilized where a ring is secured to the annulus and then the remaining composite ring/graft is snapped onto the first ring, etc. 
     Referring first to  FIGS. 9A-9D , an embodiment  600  of a prosthetic ring  602  with graft material  604  extending therefrom is configured to interlock with a second outer ring  606 . A second outer ring  606  may be used to facilitate sizing and tying of sutures  12  on the composite aortic root graft  600 . The second outer ring  606  may then be removed once the composite aortic root graft  600  is implanted. The sutures  12  are captured between the outer ring  604  and prosthetic ring  602 , enabling the surgeon to test for a proper fit. Once the fit is determined to be optimal, the composite aortic root graft  600  is tied in place. 
     The prosthetic ring  602  includes a number of suture engaging features  608 , such as grooves, to permit the composite aortic root graft  600  to be secured in place. The grooves  608  may be formed on the bottom and outer surface of the prosthetic ring  602 . Other suture engaging features described above in the other embodiments may also be used. 
     Referring to  FIGS. 10A and 10B , in another embodiment  700  with graft material  704  extending from the prosthetic ring  702 , the prosthetic ring  702  locks around a second inner ring  706 . In effect, this embodiment  700  is the reverse of the embodiment  600  shown in  FIGS. 9A-9D . 
     Referring to  FIGS. 11-13 , another embodiment of a prosthetic ring  800  for aortic root remodeling procedures is shown. The inner and outer rings  802 ,  804  of the prosthetic ring  800  of this embodiment includes peaks  806  and valleys  808  formed in the prosthetic ring  800  adapted to be fit around and suspend the aortic heart valve for aortic root remodeling procedures. Each peak  806  provides a point where the tab formed at the corner of the leaflets of the aortic valve may be supported and secured thereto. Grooves  810  may be provided to secure sutures  12  thereto, enabling temporary testing of the fit prior to sewing the sutures  12  in place. The inner and outer rings  802 ,  804  snap-fit together and may be secured in a like manner as described above for the other embodiments. The defect  814  (best seen in  FIG. 11 ) to round up the sutures  12  and provide flexibility to the prosthetic ring  800  may be in the outer ring  802  instead of the inner ring  804 . 
     The rigidity of the prosthetic ring  802  prevents under-sizing as well as oversizing of the valve while tying sutures  12  down. 
     Referring to  FIG. 13 , graft material  812  may extend from the outer ring  802 . Like the embodiment  700  shown in  FIGS. 10A and 10B , the rings  802 ,  804  may be reversed, where the graft material  812  extends from the inner ring  804  instead. The graft material  812  may be secured in place to the aortic walls to further stabilize the aorta as is known in the art. 
     In addition, a stand-alone prosthetic ring  800  may be secured around the aortic valve and graft material attached to the aorta and heart tissues separately. 
     Referring to  FIGS. 14 and 15 , alternatively, the sizer and prosthesis  900  can function each as an independent one-ring system. On the inner surface  902  of the ring  900  are a number of grooves  904  to secure the sutures. The grooves  904  themselves provide a firm but gentle grasping upon the sutures (rubber coating, etc.) much like the function performed by a valve or suture organizer. As such, the sutures can easily be moved from groove  904  to groove  904  until optimal spacing is achieved. Sutures can then be tied down in this optimal position. Sizers can be swapped out as needed before selecting the final ring prosthesis  900 . In the case of flexible or partial rings they can be attached to a rigid temporary support structure which can be cut out/away once the prosthesis  900  has been tied down. The sizer/prosthesis  900  itself can also function as the suture or valve organizer. 
     It would be appreciated by those skilled in the art that various changes and modifications can be made to the illustrated embodiments without departing from the spirit of the present invention. All such modifications and changes are intended to be within the scope of the present invention, except insofar as limited by the appended claims.