All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.
This invention relates, in general, to a surgical device and method, and more particularly to anastomotic tools and methods for their use.
Mechanical circulatory support has increasingly become a standard of care for advanced heart failure. An example of a circulatory support system is a left ventricle assist device (LVAD) for pumping blood from the heart to the ascending aorta. The LVAD is typically implanted at the apex of the left ventricle of the patient's heart. This is often accomplished by the use of an attachment ring, also referred to as a cuff, made of silicon and felt. In a conventional implantation procedure, a surgeon sutures the attachment ring to the base of the left ventricle with at least 12 pledgeted horizontal mattress 2-0 braided sutures almost full thickness through the myocardium. Corresponding sutures are then applied to the felt cuff. The sutures must then be separated and tied tight to gather the myocardium around the felt cuff. This is a time consuming process that is also open to the possibility of human error and inconsistency by the surgeon.
What is needed is a system that overcomes these and other problems. What is needed is a system that can automate at least part of the process without risking malpositioning of the cuff and sutures.
In summary, one aspect of the present invention is directed to an anastomotic system including a plurality of needles loaded with sutures and a delivery tool. The sutures include a suture core and crimp or fastener member at a proximal end of the core. An anchoring sleeve is optionally provided at a distal end. The anchoring sleeve is configured to collapse and prevent retraction of the suture after insertion through the tissue wall.
Another aspect of the present invention is directed to a method of deploying the needles using the delivery tool.
The anastomotic system of the present invention has other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated in and form a part of this specification, and the following Detailed Description of the Invention, which together serve to explain the principles of the present invention
The novel features of the invention are set forth with particularity in the claims that follow. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:
Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to those embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as defined by the appended claims.
For convenience in explanation and accurate definition in the appended claims, the terms “up” or “upper”, “down” or “lower”, “inside” and “outside” are used to describe features of the present invention with reference to the positions of such features as displayed in the figures.
In many respects the modifications of the various figures resemble those of preceding modifications and the same reference numerals followed by subscripts “a”, “b”, “c”, and “d” designate corresponding parts.
The invention relates to an improved system for performing anastomosis, and in various respects, connecting a prosthesis to tissue. In various embodiments, the system is configured to connect a vascular prosthesis to an organ such as the apex of the left ventricle of a patient's heart. In various embodiments, the system is configured to connect the prosthesis to a body lumen such as an artery or vein. The system can be configured for various applications throughout the body including end-to-end attachment.
Various aspects of the system are similar to those described in International Pub. Nos. WO1995004503A1 to Domaas et al. and WO2001041623 to Keren et al.; U.S. Pub. Nos. 2013/0282026 to Hoarau et al., 2012/0221021 to Hoarau et al., 2010/0069932 to Bilotti et al., 2004/0260318 to Gravett et al., and 2004/0068217 to Brenzel et al.; and U.S. Pat. No. 5,695,504 to Bolduc et al., U.S. Pat. No. 6,361,559 to Fleischman et al., U.S. Pat. No. 6,638,237 to Guiles et al., U.S. Pat. No. 7,309,341 to Ortiz et al., and U.S. Pat. No. 7,682,368 to Bombard et al., the entire contents of which applications and patents are incorporated herein by reference for all purposes.
Turning now to the drawings, the exemplary automatic anastomosis system includes a suture device 28, an attachment member, and a pneumatic suture delivery tool 29. The exemplary suture device is a self-anchoring suture device. The exemplary suture delivery tool incorporates a plurality of NiTinol tubular needles. The exemplary attachment member is a ventricular cuff for a left ventricular assist device (LVAD), right ventricular assist device (RVAD), or Bi-ventricular assist device (BiVAD). The attachment member is in the shape of ring and made from silicone and felt with integrated metal suture crimps. Although shown and described as a ring for attachment to a ventricular apex, one will appreciate from the description herein that various other structures may be used in place of the attachment member. In various embodiments, the delivery tool is configured to deliver the suture devices without an attachment ring, for example, in a tissue-to-tissue application.
Sectional views of the suture device 28 can be seen in
In one embodiment a proximal end of the suture core 1 is threaded through the center of the cinching crimp 2 and is mechanically crimped in place. The distal end of the suture core 1 is then threaded through the center of the anchoring sleeve 3 and fastened to the distal tip 4 of the suture core 1. In an exemplary embodiment, the sleeve and core are thermally fused using a laser.
As shown in
The upper piston chamber 27 is connected by a pneumatic channel to a needle insertion port 15 while a lower piston chamber 26 is connected by a pneumatic channel to a needle retraction port 17. The piston stem 23 that provides the air to drive the sutures 28 through the tubular NiTinol needles 24a is connected by a pneumatic channel to the suture insertion port 16. The tissue vacuum cup 14 is connected by a pneumatic channel to an external vacuum port 18. Held captive within the stationary handle 11 by the cam ring handle 12 and the crimp retainer 19 are twelve crimp dies 31.
One will appreciate from the description herein that the suture delivery tool may be modified within the scope of the invention. For example, the tool may be actuated by means other than pneumatics such as an electric drive. The tool may include any number of dies and crimps, and means other than crimping may be employed.
The attachment ring 30 is then inserted into the tissue vacuum cup 14 such that the felt retaining holes 33 in the PTFE felt ring 8 align with the locating nubs 34 (shown in
With the attachment ring 30 inserted, the tissue vacuum cup 14 is positioned over the end of the left ventricle 36 where the attachment ring is to be attached (shown in
The clinician examines the tissue position and determines if it is in a desired location. The clinician may evaluate the tissue to ensure that it is completely conformed to the inner wall of the cup so the tissue is assured to be in alignment with the delivery path of the needles. Once satisfied with the positioning of the attachment ring 30 on the left ventricle 36, a predefined air pressure is applied via a pneumatic switch to the needle insertion port 15 inducing a pressure differential between upper piston chamber 27 and lower piston chamber 26. This drives the piston assembly downward. The tubular NiTinol needles 24b bonded to the lower piston 20 are thereby driven through the retaining crimps 9 of the attachment ring 30, into the myocardium 37 of the left ventricle 36, through the felt flaps 35, through apertures 800, and then exit into the inner vacuum chamber 38 of the tissue vacuum cup 14.
With the tubular NiTinol needles 24b deployed, a predefined air pressure is applied via a pneumatic switch to the suture insertion port 16. Air flows from the port 16 through the center of the piston stem 23 and into a manifold between the piston cap 22 and the upper piston 21 where it is distributed and directed into the twelve tubular NiTinol needles. As the air flows through the needles, it creates a friction boundary layer along the surface of the sutures 28 within the needles which propels the sutures toward the distal end of the tubular NiTinol needles 24b. The suture devices 28 come to rest when the cinching crimp 2 at the proximal end of the suture core 1 is stopped by the proximal end of the tubular NiTinol needle 24b. In an exemplary embodiment, suture devices 28 are of such a length that they come to rest only after the full length of the anchoring sleeve 3 has cleared the tip of the tubular NiTinol needle 32.
Next, air pressure at the suture insertion port 16 is removed by reversing the pneumatic switch to vent the upper piston chamber 27 to atmosphere through the needle insertion port 15. Air pressure at the needle retraction port 17 is slowly increased by means of a manually controlled regulator, thus increasing the pressure in the lower piston chamber 26. The increasing pressure in the lower piston chamber slowly drives the tubular NiTinol needles 24b up by means of the bond between the needles and the lower piston 20. As the proximal end 25 of each needle retracts, it bears against the cinching crimp 2 of each suture device and compresses the suture sleeves 6 against the felt flaps 35 (shown in
After the correct cinching force has been achieved, the cam ring handle 12 is squeezed by hand towards the stationary handle 11. The rotational movement of the cam ring handle 12 translates into linear motion of the twelve crimp dies 31 by means of twelve cams 32 milled into the cam ring handle (shown in
Upon completion of the cinching process described above, attachment ring 30 is firmly secured to myocardium 37 of the left ventricle 36. Suction in central chamber 802 is discontinued to allow attachment ring 30 to separate from vacuum cup 14. Vacuum cup 14 can be lifted away from myocardium 37, which leaves attachment ring 30 attached to myocardium 37. Next, with delivery tool 29 removed from the heart, a cannulation procedure can be performed through attachment ring 30 to provide a fluid connection from the chamber of left ventricle 36 to a ventricular assist device.
A cannulation procedure may include placing a cutting instrument through the center of attachment ring 30 in order to make a hole through myocardium 37, followed by removal of the cutting instrument, followed by insertion of a cannula through the center of attachment ring 30 and into the chamber of the left ventricle 36, and then locking the cannula to the attachment ring 30. The cannula may already be connected to a ventricular assist device when it is inserted in the heart chamber, or the cannula may be subsequently connected to a ventricular assist device after the cannula has been inserted into the heart chamber.
Cannula seal 7 (
To facilitate cannulation while the heart is beating, a valvular structure can be attached to attachment ring 30 before a hole is made through myocardium 37. Thereafter, the cannulation procedure described above can be performed by passing the cutting instrument through the valvular structure to make the hole through myocardium 37. When the cutting instrument is withdrawn, the valvular structure blocks blood flow and prevents exsanguination. Next, the cannula can be inserted through the valvular structure and attachment ring 30. After the cannula is locked onto attachment ring 30, valvular structure may be disassembled so that it can be removed from attachment ring 30 and the cannula. The valvular structure can include a housing that can be separated into multiple pieces, and further include flexible valve members in the housing. The housing and flexible valve members and be similar to those described in U.S. Application Publication No. 2011/0118766 A1, which is incorporated herein by reference for all purposes.
Further information regarding the configuration of the delivery tool and its use are described in U.S. Pub. Nos. 2013/0282026 and 2012/0221021, both to Hoarau et al. Both U.S. Pub. Nos. 2013/0282026 and 2012/0221021 disclose delivery tools similar to delivery tool 29 in many respects except that the tool in those publications is configured to deploy solid needles whereas delivery tool 29 is configured to deploy needles 24 each having a needle inner lumen containing suture device 28.
In some embodiments, each needle 24 has a predefined shape in which it is curved when in a natural, unconstrained state similar to the clips described in Pub. Nos. 2013/0282026 and 2012/0221021. The axial length of needle 24 forms an arc. Suture device 28 may have slots, similar to those of the applicator tool in Pub. No. 2012/0221021, which carry and constrain needles 24 to be straight. When needles 24 are pushed out of the slots, the tip of needles 24 follow curved trajectories due to the tendency of needles 24 to return to their predefined curved shape.
In some embodiments, as shown in
As discussed above, needle 24 can be made of Nitinol, which is a nickel titanium alloy that exhibits both shape memory and superelasticity. Shape memory allows needle 24 to undergo deformation at one temperature, and subsequently return to its original, undeformed shape when needle 24 is brought to a temperature above the transformation temperature of the alloy. Superelasticity allows the needle 24 to exhibit elasticity which is many times that of ordinary metal (for example, ordinary stainless steel) when needle 24 is within a temperature range above its transition temperature. Other alloys, such as copper-based alloys known in the art, may be used to make needle 24 in order to provide shape memory and superelasticity.
In some embodiments, as shown in
As discussed above, a cinching process is performed by providing air pressure at needle retraction port 17, which results in retraction of proximal end 25 of needle 24 in a direction away from myocardium 37. The air pressure at needle retraction port 17 causes the needle 24 to be driven in a distal direction into cylinder 13 of delivery tool 29. Cinching can also be performed using pressure applied by hand through the use of other delivery tool designs (see descriptions under the heading Second Embodiment and Third Embodiment below).
As shown in
In some embodiments, the thickening of the tissue is uniform around flap 8. In some embodiments, the thickening of the tissue is non-uniform around flap 8. In some embodiments, thickening is uniform in thickness around flap 28. Thickened portion 104 is squeezed between curved segments of flap 8 so that a pressure is applied to thickened portion 104. The air pressure at needle retraction port 17 can be controlled so that driving of needle 24 in a distal direction can be performed to achieve a desired pressure on the tissue. Thickened portion 104 is under stress, and the amount of thickening is selected to achieve a desired pre-stressing of the tissue.
A second embodiment of a delivery tool is described below in connection with
Attachment ring 30 has bottom end 132 and top end 134. Bottom end 132 is secured to biological tissue and top end 134 is configured to engage forward segment 112 of delivery tool 111. In some embodiments, attachment ring 30 includes features configured to connect with a conduit, such as an inflow conduit of a ventricular assist device (VAD), after attachment ring 30 has been secured to biological tissue, such as the ventricular apex of the heart. Methods for securing an inflow conduit to the ventricular apex by means of an attachment ring are described in U.S. Application Publication Nos. 2011/0118766 A1, 2011/0118833 A1, and 2011/0118829 A1, which are incorporated herein by reference for all purposes.
In use, attachment ring 30 is engaged to and carried by connector mechanism 126 at forward segment 112 of delivery tool 111. The user positions forward segment 112 at the desired location on biological tissue where attachment ring 30 is to be secured. The user actuates the various controls on delivery tool 111 to simultaneously deploy multiple clips, or other type of anastomotic securements, that secure attachment ring 30 to the tissue and to disconnect connector mechanism 126 from attachment ring 30.
In some embodiments, when the user actuates clip deployment handle 118, clips are pushed out of delivery tool 111 such that the tips of clips pass through attachment ring 30 and into underlying tissue. The tips initially move downward in a substantially straight trajectory into the tissue. Thereafter, each tip follows a curved trajectory that extends radially outward and away from attachment ring 30 and returns upward out of the tissue. The tips then turn downward and return toward attachment ring 30 and stop at a position adjacent to or on an outer surface of attachment ring 30. Thus it will be understood that during deployment out of delivery tool 111, the clips pass through and curl back toward attachment ring 30. As the user continues to pull clip deployment handle 118, a portion of attachment ring 30 clamps down onto or traps the tips, and prevents the tips from moving backwards into the tissue. Next, as the user actuates cinching handle 122, the rear segment of each clip is pulled up away from the tissue and into delivery tool 111. Since the tip of each clip is held in place by attachment ring 30, pulling the rear segment of each clip causes the middle segment of each clip to cinch or tighten against the tissue. This tightening of the clips increases engagement between the tissue and attachment ring 30. When the user actuates release knob 123, the rear segment of each clip is released from delivery tool 111. Features on each clip and attachment ring 30, such as protrusions and catch features, prevent the rear segment of each clip from slipping or moving down toward the tissue, which maintains the cinched or tightened state of the clips. When the user actuates disengagement knob 124, attachment ring 30 is released by connector mechanism 126 of delivery tool 111, which allows delivery tool 111 to be pulled away from the tissue while attachment ring 30 remains attached to the tissue.
In use, engagement device 700 is fitted around and engaged to forward segment 112 of delivery tool 111. Engagement device 700 is configured to temporarily engage forward segment 112 of delivery tool 111 to biological tissue to facilitate accurate positioning of attachment ring 30 to the tissue and to facilitate deployment of clips into the tissue. Engagement device 700 is configured to selectively engage onto and disengage from the tissue with the application and removal of suction. Engagement device 700 is set to engage onto tissue, with application of suction, when clips are deployed and cinched by delivery tool 111. Engagement device 700 is set to disengage from the tissue, with a partial decrease or complete removal of suction, after the clips are deployed and before delivery tool 111 is pulled away from the tissue and attachment ring 30.
As shown in
Fluid conduit 704 is a tube that extends from top or rear end 710 (
Fluid conduit 704 includes rear tube 704a, ring tube 704b, and a plurality of forward tubes 704c. Rear tube 704a is configured to be connected to a negative pressure source or suction pump. An end of rear tube 704a is connected to ring tube 704b which is connected to ends of forward tubes 704c. The opposite end of forward tubes 704c are connected to suction apertures 712 (
Coupling member 706 is in the shape of a tube and has central lumen 714. Central lumen 714 is sized to receive forward segment 112 of delivery tool 111. Six contact members 702 are arranged circumferentially around central lumen 714 at substantially equal circumferential spacing of about 60 degrees. In other embodiments, an engagement device can include a lesser or greater number of contact members 702.
Referring to
As shown in
As shown in
In some embodiments, concave walls 703 may be made of a flexible material, such as silicone rubber, to facilitate formation of a seal between peripheral edge 705 and the surface of tissue. As negative pressure builds in the cavity between concave walls 703 and the tissue surface, concave walls 703 may tend to collapse toward the tissue surface. Such collapse may result in deformation of peripheral edges 705 that causes loss of the air seal between peripheral edges 705 and the tissue. Also, if suction aperture 712 contacts tissue surface, suction and thus the area of tissue surface engagement will be limited to the area immediately surrounding suction aperture 712. Protrusions 720 are configured to help maintain the air seal and to prevent suction aperture 712 from contacting the tissue surface so that the area of tissue surface engagement extends out to peripheral edges 705 of contact members 702.
In some embodiments, protrusions 720 are configured to provide frictional engagement against the tissue surface. As negative pressure builds in the cavity between concave walls 703 and the tissue surface, concave walls 703 may tend to collapse toward the tissue surface so that protrusions 720 presses against and frictionally engage the tissue surface.
The clips for anchoring attachment ring 30 to biological tissue are contained within forward segment 112 of delivery tool 111. The configuration of each clip can be as shown in
When loaded inside delivery tool 111, curved segment 41 is in a straightened configuration. When deployed out of delivery tool 111, tip 44 will initially follow a straight path through attachment ring 30 and into the biological tissue. As curved segment 41 exits delivery tool 111, curved segment will autonomously return to a curved configuration, which causes tip 44 to follow a curved path beneath the tissue surface. Due to the curved path, tip 44 exits the tissue surface and loops back toward attachment ring 30. Attachment ring 30 includes features that clamp and/or trap tip 44. As tip 44 exits the tissue surface, annular surface 718 (
In some embodiments, band 742 of connector 740 is fixedly attached to forward segment 112 of delivery tool 111 with no ability to adjust the axial position of contact members 702 of engagement device 700 relative to forward segment 112 and attaching ring 30. In other embodiments, band 742 is slideably attached to forward segment 112 to allow a medial practitioner to selectively adjust and fix the axial position of contact members 702 relative to forward segment 112 and attachment ring 30.
In use, attachment ring 30 (not shown in
In other embodiments, engagement device 800 is combined with all the features of engagement device 700 such that coupling member 706 is replaced by suction cap 802. Alternatively, coupling member 706 can be fitted over and attached onto suction cap 802. Suction can be applied to contact members 702 and/or suction cap 802 to engage delivery tool 111 to tissue. Applying suction to contact members 702 helps to stabilize areas of tissue spaced apart from and surrounding attachment ring 30. Applying suction to suction cap 802 helps to stabilize areas of tissue directly beneath attachment ring 30. While negative pressure is generated within contact members 702 and/or suction cap 802, clips 136 are deployed out of delivery tool 111 and into the underlying tissue.
During a surgical procedure, engagement device 700, 800 and delivery tool 111 are fixed to each other. Delivery tool 111 is hand held by the surgeon who manipulates controls on the delivery tool. As the surgeon places delivery tool 111 at the target tissue, engagement device 700, 800 will engage surrounding tissue with application of suction and thereby prevent or minimize relative movement between delivery tool 111 and the target tissue. Engagement device 700, 800 is not fixedly connected to a surgical bed, sternum retractor, or other stationary structure. Engagement device 700, 800 does not fix or stabilize the surrounding tissue relative to a stationary structure. Engagement device 700, 800 fixes or stabilizes the surrounding tissue relative to delivery tool 111, which moves under the direction of the clinician. Thus, after engagement device 700, 800 attaches to surrounding tissue with suction, and if the clinician manually moves delivery tool 111 left, right, up or down within the patient's body cavity, delivery tool 111 will remain stationary relative to the target tissue. Delivery tool 111 will also remain at the target tissue even if the target tissue moves due to pulsatile blood flow, unexpected change in the patient's body position, or other reason. Thus it will be understood that delivery tool 111 and engagement device 700, 800 are designed to move with the target tissue and not to slip relative to the target tissue. Engagement device 700, 800 enables delivery tool 111 to be “stuck” with the target tissue, which helps to deploy the clips at the precise location selected by the surgeon. If desired, suction can be partially decreased or completely removed to allow the surgeon to adjust the position of delivery tool 111 on the tissue.
As discussed above, negative pressure or suction is applied to the engagement device 700, 800 so that engagement device 700, 800 attaches to the target tissue. A particular amount of negative pressure is necessary for the purpose of deploying the clips with consistency from delivery tool 111. Inconsistent clip deployment may take the form of undue variation in depth, direction, and/or curvature in the path of travel of the clips. The amount of negative pressure needed for consistent clip deployment may depend on multiple factors, including but not limited to the number of clips being deployed, the type of tissue into which the clips are being deployed, and the size of the surface area to which vacuum is being applied. A method according to the invention can include the steps discussed above in combination with either one or both of (1) the step of selecting or determining an amount of negative pressure that corresponds to a threshold level of security between the delivery tool and the target tissue, and (2) the step of applying the preselected or predetermined amount of negative pressure to the engagement device 700, 800 during clip deployment. In various embodiments, the determined amount of negative pressure is selected to be below a maximum threshold. The maximum threshold may be selected to reduce the risk of injury to the target tissue.
Engagement device 700, 800 can be used for locating and targeting the site for attaching a VAD inflow conduit during an off-pump, minimally invasive surgical procedure as opposed to a conventional, open heart procedure. The term “off-pump” means that clip deployment is performed while the heart is beating and without a heart-lung or cardiopulmonary bypass procedure being performed. For example and without limitation, delivery tool 111 and engagement device 700, 800 can be introduced into the chest cavity of a patient via an intercostal approach or via a small incision between the ribs of the patient. In this example, a sternotomy and spreading of the left and right rib cage apart are avoided. After introduction into the chest cavity, the clinician can place delivery tool 111 on the ventricular apex of the heart (the target tissue) and apply a sufficient amount of negative pressure to engagement device 700, 800 that substantially prevents relative movement between the target tissue and delivery tool 111.
Engagement device 700, 800 applies preset or adjustable force loading between the delivery tool 111 and the tissue. This loading is important for the success of deploying the clips. When delivery tool 111 is used in concert with engagement device 700, 800, and as a vacuum is applied, delivery tool 111 is pressed downward (as a result of the suction) against the tissue. The downward force (also referred to as load) applied by delivery tool 111 on the tissue depends upon a connection device that connects engagement device 700, 800 and delivery tool 111 together. The exemplary connection device allows for control of the amount of force on the tissue so that the force is simultaneously (1) below a maximum level that would damage the tissue, and (2) at or above a minimum level needed to ensure that the clips are properly deployed without undue variation in depth, direction, and/or curvature in the path of travel of the clips. Control of the amount of force on the tissue can be accomplished by adjusting the distance between the forward tip of attachment ring 30 and the base (736 in
Engagement device 700, 800 keeps the deployment site clear of possible obstruction. Engagement device 700, 800 completely engages the tissue area required for clip deployment and prevents surrounding tissue and other surgical devices from entering into that tissue area and interfering with clip deployment.
Engagement device 700 has contact members 702 that function as individual pods or feet that provide suction to discrete areas of tissue surrounding a central area into which clips are deployed. The central area is referred to as the clip deployment site. The discrete areas of tissue can be separated from each other by areas of tissue which receive no suction. Engagement device 800 has suction cap 802 that provides suction to a circular area that includes the clip deployment site.
As shown in
As shown in
The orientation and shape of the suction ports serve multiple purposes. Angle A1 is selected to allow for easy attachment of engagement device 700 to the heart. Angle A1 allows engagement device 700 to conform to the curved outer surface 734 of the heart. Angle A1 can be within the range of about 10 degrees to about 80 degrees, or more narrowly within the range of about 20 degrees to about 70 degrees, or at about 60 degrees. The appropriate angle depends in part on the physical size of the patient's heart. A relatively small angle would be more suitable for the curved outer surface of a relatively small heart, and a relatively large angle would be more suitable for the curved outer surface of a relatively large heart.
The orientation and shape of the suction openings will remodel the clip deployment site for engagement with delivery tool 111 and attachment ring 30. The configuration of the suction openings will pull the heart tissue 734 up to form an ideal shape for engagement with delivery tool 111 and attachment ring 30. The slanted angle of the engagement device surface in contact with the heart tissue 734, in combination with the vacuum suction, will change the shape of the heart so it can conform to that of the engagement device and/or attachment ring 30.
The orientation and shape of the suction openings minimize the movement of the tissue during clip deployment.
The angular orientation of the suction opening, Angle A1, can be adjusted according to the surgeon's need. Contact members 702 are adjustable and designed to contour to the shape of the outer surface of the heart. Making joint 708 (
An engagement device can have an annular or ring-shaped contact member 750, as shown in
Interior surface 760 is oriented at acute Angle A2 relative to central axis 762. Angle A2 can be about 25 degrees. In other embodiments, Angle A2 can be within the range of about 10 degrees to about 80 degrees, or more narrowly within the range of about 20 degrees to about 70 degrees, or at about 60 degrees. Angle A2 is selected with the purpose of maintaining contact with the heart surface which is not flat, but curved so that ring-shaped contact member 750 can “cup” the heart.
Contact member 750 includes multiple attachment points 764 (
As shown in
In other embodiments, engagement device 700, 800 has attachment points around the outer perimeter of the device. The attachment points are configured to receive and retain add-on devices, such as a viewing port or a light source. The attachment points can be the same as or similar to accessory attachment points 770 described in connection with
A third embodiment of a delivery tool is described below in connection with
In use, clips 136 (also referred as needles) are contained within forward end 212 of delivery tool 211. Each clip 136 includes wire body having forward segment 40 and rear segment 42. Forward segment 40 has sharp tip 44 for piercing a portion of attachment ring 30 and underlying biological tissue. Catch 46 protrudes out from rear segment 42 and is pushed forward during operation of delivery tool 211. Clips 136 are constrained in a straightened configuration within forward end 212 of delivery tool 211. In various embodiments, the clips are formed of shape memory material and make use of the shape memory properties. When deployed out of forward end 212, exemplary clips 136 will autonomously coil radially outward away from axial centerline 54 (
Referring to
Clip grooves 52 have sidewalls 57 that extend substantially parallel to axial centerline 54 and substantially non-perpendicular to outer surface 145 of clip tube 48. In other embodiments, sidewalls 57 are substantially perpendicular to outer surface 145.
Catch 46 of each clip 136 abuts sidewalls 57 of clip groove 52, which prevents clip 136 from twisting about its central axis 39 while contained inside clip groove 52. Catch 46 and sidewalls 57 help to ensure that the curved trajectory of tip 44 will be in the desired direction relative to attachment ring 30. The direction followed by tip 44 is controlled in part by the angle of sidewalls 57 and by the initial shape of clip 136 prior to being loaded in delivery tool 211. As shown in
In
There are twelve clip holders 47 circumferentially arranged on clip tube 48 at substantially equal angular spacing of about 30 degrees apart from each other. In other embodiments, a fewer number or a greater number of clip holders 47 are arranged around the clip tube than what is shown in
Cinching tube 58 is a hollow, cylindrical sleeve. Cinching tube 58 contains and is substantially coaxial with clip tube 48. Clip pusher surface 51 (
A method for anchoring attachment ring 30 will now be described together with delivery tool 211, though it should be understood that other delivery tools may be used to perform the method. It is to be understood that, depending on the type of delivery tool used and depending on clinical need, some steps described below may be performed simultaneously as a single step, performed in a sequence other than described below, or may be omitted.
Exemplary steps for delivery tool stabilization are as follows. Referring to
Exemplary steps for clip deployment are as follows. The user rotates handle 218 to begin deployment of clips 136 out of delivery tool 211. Handle rotation causes clamping tube 64 (
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.
This application claims the benefit of U.S. Provisional Application No. 61/799,877, filed Mar. 15, 2013, the entire disclosure of which is incorporated herein for all purposes by reference.
Number | Date | Country | |
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61799877 | Mar 2013 | US |