Abstract:
A tool for facilitating access to the inside of a vessel and/or surgery on a vessel or an organ connected to the vessel. The vessel has a proximal end and a distal end, while the tool has a substantially cylindrical band and an arm. The band has a deployed configuration capable of opening the proximal portion of the vessel. The arm is connected to the band and has a deployed configuration capable of at least partially flattening the distal end of the vessel to improve the view inside the vessel. When deployed in a vessel, the tool holds the vessel in an open configuration and provides the physician with a surgical operating field, and the ability to pass a prosthesis through said tool and in a desired location within an organ.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to surgical instruments, and more particularly, to surgical instruments for use in prosthetic heart valve procedures and other vascular procedures requiring access to the inside of a vessel or organ. 
       BACKGROUND 
       [0002]    Conventional surgical heart valve repair and/or replacement procedures generally require complete dissection of the ascending aorta in order to suture the replacement valve (e.g., a prosthetic aortic valve) to the native valve annulus. With surgical sutureless heart valve replacement procedures, however, complete dissection of the ascending aorta would not be necessary for suturing the valve in place (i.e., because no suturing is required), but is still generally required to gain access to the native valve and valve annulus and generally to the inside of the vessel. 
       SUMMARY 
       [0003]    The present invention, according to one embodiment, is a tool for facilitating exposure of an inside portion of a vessel or an organ, the vessel having a proximal end and a distal end. The tool comprises a substantially cylindrical band having a deployed configuration capable of opening the proximal portion of the vessel and an arm connected to the band. The arm has a deployed configuration capable of at least partially flattening the distal end of the vessel. According to various embodiments, the vessel is an aorta. 
         [0004]    The present invention, according to another embodiment, is a tool for surgery facilitating exposure of an inside section of a vessel. The tool comprises an element having a band capable of creating an operating field to the inside of a first portion of the vessel and an arm capable of at least partially flattening a second portion of the vessel. According to some embodiments, the element is sized and dimensioned so that a prosthetic heart valve can travel therethrough. In some embodiments, the element is made from a lightweight material, such as a biocompatible polymer. According to some embodiments, the outside of at least a portion of the element is textured so as not to tear the intima of the vessel. In some embodiments, the band has a deployed configuration capable of exerting an outward radial force on the vessel wall, the outward radial force of the element being sufficient to adapt to different inner diameters of the vessel, while avoiding destructive stretching of the inner wall of the vessel. 
         [0005]    According to some embodiments, the arm comprises a bar having a deployed configuration generally perpendicular to a plane of the band. The bar may have an exemplary length of from about 3 cm to about 5 cm. The arm may have a generally t-shaped deployed configuration. 
         [0006]    The present invention, according to another embodiment, is a method of surgery comprising, partially dissecting a vessel to create an opening of a dissected vessel, inserting a tool through the opening, and exposing an operating field that is located within the vessel or organ connected to the vessel through the use of the tool. The method of surgery may further comprise providing a valve prosthesis and passing the prosthesis through the opening made by the tool. In some embodiments, the method further includes implanting the valve prosthesis. 
         [0007]    While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a perspective partial cut-away view of a surgical tool in a deployed state according to one embodiment of the present invention. 
           [0009]      FIGS. 2A-2C  are schematic elevation, plan, and end views, respectively, of the surgical tool of  FIG. 1 . 
           [0010]      FIGS. 3A and 3B  are plan views schematically illustrating the surgical tool of  FIG. 1  partially and fully deployed in a patient&#39;s ascending aorta. 
           [0011]      FIG. 4  is an end view schematically illustrating the surgical tool of  FIG. 1  deployed in a patient&#39;s ascending aorta taken along the line  4 - 4  of  FIG. 3B . 
           [0012]      FIGS. 5A and 5B  are elevation and side schematic views of a portion of an alternative surgical tool according to another embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]      FIG. 1  is a perspective partial cut-away view of a surgical tool  10  in a deployed state within a patient&#39;s ascending aorta  14  according to one embodiment of the present invention. As is known, and as shown in  FIG. 1 , the ascending aorta  14  is coupled to the left ventricle  18 . During normal operation, the left ventricle  18  pumps blood out of the heart through the aortic valve  20  and into the ascending aorta  14 . The aortic valve  20  is a semilunar valve including a set of valve leaflets  21  surrounding an aortic annulus  22 , which is defined by the periannular tissue located at the most distal portion of the left ventricular outflow tract. 
         [0014]    In the illustrated embodiment, the surgical tool  10  is deployed through a partial incision  24  in the wall of the ascending aorta  14  in a manner as would be used, for example, to facilitate surgical procedures in the vicinity of the aortic valve. Exemplary procedures that may be performed in conjunction with the surgical tool  10  include, without limitation, repair of the aortic valve  20 , replacement of the aortic valve  20 , aortic annuloplasty, repair procedures in the left ventricle, and similar procedures. In one embodiment, the surgical tool  10  is advantageously utilized for implantation of a surgical sutureless prosthetic heart valve to replace the aortic valve  20 . As explained in further detail below, the surgical tool  10  operates, at least in part, to provide an open operating field through which the surgeon or other clinician can perform the particular procedure. While much of the following disclosure is directed to use of the surgical tool  10  for use in procedures relating to the aortic valve  20 , one of ordinary skill in the art will readily recognize that the tool  10  will have utility for a wide variety of other procedures requiring access into various portions of the vasculature system or organs. 
         [0015]    In the illustrated embodiment, the surgical tool  10  includes a band  30  and an arm  36  coupled thereto. As shown, the band  30  is sized to be inserted into the ascending aorta  14  proximal to the incision  24  (i.e., closer to the left ventricle), and the arm  36  extends distally (i.e., farther from the left ventricle) from the band  30  and across the incision  24 . In  FIG. 1 , for illustration purposes, the wall of the ascending aorta  14  proximal to the incision  24  is shown cut-away to better illustrate the position of the band  30 . In practice, the band  30  is inserted into the ascending aorta  14  proximal to the incision  24  and is allowed to expand into contact with the internal surface (i.e., intima) of the vessel. The band  30  is configured to hold open and support the wall of the that portion of the ascending aorta  14  (or other desired vessel) with sufficient radial force to substantially inhibit migration of the band  30  from a desired location near the incision  24 . The band  30  thus provides a relatively large operating field through which the physician can access and visualize the aortic valve  20 , the valve leaflets  21 , and the aortic annulus  22 . 
         [0016]    As shown in  FIG. 1 , the arm  36  extends distally across the incision  24 . As shown, however, the arm  36  is not inserted into the ascending aorta  14 . Rather, the arm  36  contacts the outside anterior wall of the ascending aorta  14  and urges this anterior wall toward the posterior wall so as to somewhat flatten the ascending aorta  14  distal to the incision  24 . This flattening of the portion of the ascending aorta  14  distal to the incision  24  (which would otherwise interfere or block the operating lumen within the aorta  14  proximal to the incision  24 ) further enlarges the operating field available to the physician. Thus, the surgical tool  10  operates to maximize the operating field available to the physician while requiring only a partial incision about the circumference of the ascending aorta  14  (i.e., without requiring complete dissection of the ascending aorta  14 ). 
         [0017]    While the above discussion refers to the arm  36  urging the anterior wall of the ascending aorta  14  toward the posterior wall thereof, the use of the surgical tool  10  is not limited to only an anterior/posterior circumferential orientation. That is, the surgical tool  10  can be oriented so as to locate the arm  36  anywhere about the circumference of the ascending aorta  14 . Additionally, although the arm  36  will typically be positioned generally diametrically opposite the center of the incision  24 , this is not a requirement. 
         [0018]      FIGS. 2A-2C  are schematic elevation, plan, and end views, respectively, of the surgical tool  10  according to one embodiment of the present invention. As shown in  FIGS. 2A-2C , in the illustrated embodiment, the band  30  is generally cylindrical and defines a proximal edge  40 , a distal edge  44 , an outer face  48 , and an inner face  52 . 
         [0019]    As further shown, the arm  36  has a proximal end  56  and a distal end  60  defining a length  61 , an upper face  62 , and a lower face  63 , and includes a lateral member  64  and a cross member  68 . Additionally, in the illustrated embodiment, the proximal end  56  of the arm  36  is coupled to the band  30  by a hinge  72  located at or proximate the distal edge  44  of the band  30 . In the illustrated embodiment, the lateral member  64  extends away from the hinge  72 , and the cross member  68  is located on the lateral member  64  opposite the hinge  72 , such that the distal end  60  of the arm  36  is generally T-shaped. 
         [0020]    As illustrated in  FIG. 2A , the arm  36  is angularly adjustable with respect to the band  30  by virtue of the hinge  72 . Thus, the arm  36  is pivotable or actuatable between a longitudinally compact configuration (not shown), in which the arm  36  is substantially parallel to the general plane of the band  30 , and the deployed configuration of  FIGS. 2A-2C  in which the arm  36  extends upward and is substantially perpendicular to the general plane of the band  30 . The hinge  72  can take on any suitable configuration. In various embodiments, the hinge  72  is a separate structure attached to both the band  30  and the proximal end  56  of the arm. In other embodiments, the hinge  72  is integral to one or both of the band  30  and the arm  36 . In various embodiments, the hinge  72  is in the form of a so-called “living hinge,” which structures are well known in the art and need not be described in detail here. 
         [0021]    In various embodiments, the arm  36  is pre-configured to be biased toward the deployed configuration of  FIGS. 2A-2C , and temporarily retained in the compact configuration by any suitable retaining structures (e.g., sutures). In such embodiments, once the band  30  is placed in the proximal ascending aorta  14  as desired by the physician, the retaining structures can be removed or otherwise disabled (e.g., the sutures can be cut) so as to allow the arm  36  to rotate to its deployed configuration, thereby flattening the ascending aorta  14  distal to the incision  24 . In other embodiments, the arm  36  is manually rotatable or adjustable by the physician. 
         [0022]    As will be appreciated, the arm  36  is configured such that all or a substantial portion of the lower face  63  will contact and bear upon the outer surface of the ascending aorta  14  distal to the incision  24  when deployed. In various embodiments, all or a portion of the lower face  63  is textured to help minimize damage to the vessel wall. In other embodiments, the lower face  63  is not textured. Because the upper face  62  is not generally configured to contact the wall of the aorta, in various embodiments, this face is generally smooth (i.e., not textured). Of course, the upper face  62  can be textured as well if desired. 
         [0023]    In the illustrated embodiment, the arm  36  is shown as a generally unitary structure. This is not a requirement, however, and in other embodiments, the arm  36  can be formed from one or more wires, rods, etc. into the desired shape. Of course, the arm  36  need not be T-shaped as shown. Additionally, the arm  36  need not be substantially flat as shown. Rather, in various embodiments, all or portions of the arm  36  can have other cross-sectional shapes, e.g., cylindrical. In some exemplary embodiments, the cross member  68  is formed with a slight curvature such that it is concave from the perspective of the center of the vessel. 
         [0024]    As further shown, the band  30  is generally cylindrical, with the inner face  52  defining an opening  76 , the outer face  48  defining an outer diameter  78 , with the separation between the outer and inner faces defining a width  80 . The outer diameter  78  is generally selected such that the outer face  48  contacts and bears upon the intima of the ascending aorta  14  in which the band is inserted. Such contact is selected to be sufficient to prevent or at least substantially inhibit translation of the band  30  within the desired vessel (e.g., ascending aorta  14 ), and also to provide sufficient support to maintain the desired operating field, but at the same time to avoid unnecessary stretching of the wall of the vessel. The width  80  is also selected to optimize the contact area between the outer face  48  and the intima of the ascending aorta  14  without interfering with the implantation of the valve prosthesis. In exemplary embodiments, the width  80  is between about 1 and about 15 mm. In other exemplary embodiments, the width  80  is between about 5 and about 10 mm. 
         [0025]    Similar to the lower face  63  of the arm  36  described above, the band  30  is configured such that all or a substantial portion of the outer face  48  will contact and bear upon the intima of the ascending aorta  14  proximal to the incision  24  when deployed. In various embodiments, all or a portion of the outer face  48  is textured to help minimize damage to the vessel wall. In other embodiments, the outer face  48  is not textured. Because the inner face  52  is not generally configured to contact the intima of the aorta, in various embodiments, this face is generally smooth (i.e., not textured). Of course, the inner face  52  can be textured as well if desired. 
         [0026]    In one embodiment, the band  30  is radially expandable from a radially compact configuration (not shown) suitable for ease of deployment, to a radially expanded, deployed configuration such as shown in  FIGS. 2A-2C . In such an embodiment, the outer diameter  78 , when the band  30  is radially un-restrained, is larger than the inner diameter of the corresponding portion of the ascending aorta  14  in which the band  30  will be inserted. Thus, upon insertion into the ascending aorta  14  and subsequent expansion, the band  30  will exert an outward radial force on the inner wall of the ascending aorta  14 . The band  30  is configured such that the applied radial force is sufficient to allow the band to adapt to a range of inner aortic diameters, but not to the extent that the ascending aortic wall is unnecessarily stretched. 
         [0027]    In various embodiments, the expandable band  30  may be self-expanding, in which case the band  30  is pre-biased to its expanded configuration, and is retained in its radially compact configuration prior to insertion into the ascending aorta  14  via a suitable retaining structure. After insertion into the ascending aorta  14 , the retaining structure is removed or disabled, thereby allowing the band  30  to attempt to expand to its un-restrained outer diameter  78 . Alternatively, the band  30  may be manually expandable by another device, e.g., a balloon catheter. Various technologies and configurations for self-expanding and/or balloon-expandable structures are known, such as, for example, technologies used in the design and manufacture of stents for interventional cardiology procedures, which technologies could be utilized in the design and manufacture of the band  30 . 
         [0028]    The overall dimensions of the band  30  and the arm  36  can be tailored to provide the desired functionality (i.e., support of the ascending aorta  14  proximal to the incision and flattening of the ascending aorta  14  distal to the incision). As will be appreciated, the outer diameter  78  is selected based on the size of the ascending aorta  14  in which it is to be inserted. Additionally, the opening  76  is generally sized to maximize the operating field available to the physician. As will be appreciated, the size of the opening  76  is dictated by the outer diameter  78  and the thickness of the material making up the band  30 . In various embodiments, the band  30  is made from a lightweight material having sufficient strength to provide the desired support, but still allowing the thickness of the band  30  to be minimized, thereby maximizing the size of the opening  76 . In various embodiments, the opening  76  is sized to permit passage of a prosthetic heart valve (e.g., a surgical sutureless prosthetic aortic valve) therethrough, along with other instruments necessary for implantation of the prosthetic valve. 
         [0029]    The T-shaped profile of the arm  36  advantageously allows the width of the lateral member  64  to be minimized, so as to not unnecessarily stiffen the band  30  at the attachment (e.g., the hinge  72 ) between the two structures, yet still provide significant contact between the arm  36  and the wall of the ascending aorta  14 . Additionally, the length  61  of the arm  36  can be varied as needed. According to some embodiments, the length of the arm  36  is approximately equal to the diameter of the band  30  when the band is in its compressed form. In various embodiments, the length  61  is selected in the range of from about 1 cm to about 5 cm. In other embodiments, the length  61  is selected in the range of from about 3 cm to about 5 cm. In another variant of the invention the arm could also have a concave or convex profile as viewed from above, and/or the top part of the T could have the same characteristics. 
         [0030]    The band  30  and/or arm  36  may be made from any material having suitable physical characteristics. In various embodiments, the band  30  and/or the arm  36  are made from a lightweight, biocompatible polymeric or metallic material. In embodiments where the band  30  is expandable, at least the band  30  is made from a biocompatible polymer or metal having shape memory and/or super-elastic properties. One such class of shape-memory and super-elastic materials are nickel-titanium alloys such as nitinol. In various embodiments, for example, where the arm  36  is self-deployable, the hinge  72  may also be made from stainless steel or a shape-memory material such as nitinol. 
         [0031]      FIGS. 3A and 3B  are plan views schematically illustrating the surgical tool  10  partially and fully deployed, respectively, in a patient&#39;s ascending aorta. In  FIG. 3A , the surgical tool  10  is partially deployed, in that the band  30  is inserted through the incision  24  into the proximal ascending aorta  14   p , and the arm  36  is as yet undeployed, such that the cross-member  68  is positioned adjacent to the band  30 . In  FIG. 3B , the arm  36  has been deployed (i.e., angularly adjusted to displace the cross-member  68  away from the band  30 ), thereby at least partially flattening the distal ascending aorta  14 d. As illustrated in  FIGS. 3A and 3B , the surgical tool  10  is amenable to implantation by the physician through a relatively small aortic incision. The incision  24  need only be of a length sufficient to allow insertion of the surgical tool  10 , while in its compressed configuration. In various exemplary embodiments, the incision  24  is made through about half of the diameter of the aortic wall. 
         [0032]      FIG. 4  is an end view schematically illustrating the surgical tool  10  deployed in a patient&#39;s ascending aorta taken along the line  4 - 4  of  FIG. 3B . As shown in  FIG. 4 , in the deployed state, the band  30  contacts and supports the proximal ascending aorta  14   p , while the deployed arm  36  has substantially flattened the distal ascending aorta  14   d . Thus, the operating field available to the physician (e.g., for visualizing and accessing the diseased aortic valve  20 ) is maximized while still allowing the length of the incision  24  to be relatively short (as compared to a complete aortic dissection). Additionally, in the embodiment illustrated in  FIG. 4 , the arm  36 , including the cross-member  68 , is curved in the same general shape as the shape of the ascending aorta  14  so as to further reduce the extent to which the arm  36  extends radially into the operating field. In one embodiment, the arm  36  is pre-shaped to generally correspond to the aortic anatomy. In other embodiments, all or portions of the arm  36 , e.g., the cross-member  68 , are flexible so as to adapt or conform to the anatomy as desired. 
         [0033]      FIGS. 5A and 5B  are elevation and side schematic views of a portion of an alternative surgical tool  110  according to another embodiment of the present invention. As shown in  FIGS. 5A and 5B , the surgical tool  110  includes an arm  136  which is configured to be coupled to a band such as the band  30  of the tool  10  discussed above. The arm  136  is overall configured in substantially the same or an identical manner as the arm  36  of the tool  10 . As such, the arm  136  has a proximal end  156  and a distal end  160 , an upper face  162 , and a lower face  163 , and includes a lateral member  164  and a cross member  168 . In the illustrated embodiment, the cross member  168  is located on the lateral member  164  opposite the proximal end  156 , such that the distal end  160  of the arm  136  is generally T-shaped. 
         [0034]    Additionally, the arm  136  includes a mirror  200  pivotally coupled to a standoff  210 . As shown, the standoff is attached to and supported from the upper face  162  of the cross-member  168 . The mirror  200  can pivot about the attachment point to the standoff  210 , and can be oriented to provide enhanced visualization of the inside of the aorta and/or the operating field in general. 
         [0035]    Various modifications and additions can be made to the exemplary embodiments discussed without departing from the scope of the present invention. Accordingly, the scope of the present invention is intended to embrace all such alternatives, modifications, and variations as fall within the scope of the claims, together with all equivalents thereof.