Apparatus and Methods for Anastomosis
Apparatus and methods for performing an anastomosis. More particularly, the apparatus may be used to perform a single or multiple anastomosis with the ability of maintaining fluid flow (e.g., blood) through the anastomosis vessel according to one aspect of the invention.
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This application hereby claims priority to copending provisional application No. 60/127,862, which was filed on Apr. 5, 1999, and which is hereby incorporated herein, by reference thereto, in its entirety.
FIELD OF THE INVENTIONThe present invention relates to apparatus and methods for performing an anastomosis. The apparatus may be used to perform a single or multiple anastomosis with the ability of maintaining fluid flow (e.g., blood) through the anastomosis vessel.
BACKGROUND OF THE INVENTIONThe occlusion of the arteries can lead to insufficient blood flow resulting in discomfort and risks of angina and ischemia. Significant blockage of blood flow in the coronary artery can result in damage to the myocardial tissue or death of the patient. In most cases, occlusion of the artery results from progressive long term deposits of plaque along the artery wall. While such deposits may be concentrated and occlude the artery at a particular site, the deposits are most certainly present throughout the arteries and the vascular system.
Coronary artery bypass graft (CABG) surgery is a surgical procedure performed in severe cases of coronary blockages. CABG procedures involve anastomosing an artery to a vascular graft which restores the flow of blood by establishing another pathway around the occluded vasculature. One problem encountered in the procedure is the need of performing the procedure while simultaneously maintaining sufficient function of the patient's circulatory system.
A CABG procedure may involve arresting the heart so that blood flow is diverted from the vessel to be anastomosed. The patient's blood circulation is maintained by a cardiopulmonary bypass (CPB). This bypass is accomplished by diverting the blood flow at selected arterial locations. The blood is diverted to the bypass system for release of carbon dioxide and subsequent oxygenation. Then, the blood is returned to the patient via a pump. Examples of these procedures are found in U.S. Pat. No. 5,799,661 to Boyd et al. which discloses a device and method for performing CABG surgery for multi-vessel coronary artery disease through port-access or closed-chest thorascopic methods; and U.S. Pat. No. 5,452,733 to Sterman et al. which discusses performing grafts with an efficacy equal to or greater than conventional open surgical bypass techniques.
Another CABG procedure involves operating on a beating heart and eliminates the need for a CPB. However, the procedure still requires diverting blood flow for a proximal anastomosis, such as one which attaches graft material (e.g., a graft vessel) to the ascending aorta.
First, the blood flow may be diverted by aortic clamping. Among the drawbacks associated with aortic clamping are an increased chance of trauma to the arteries caused by ligatures at the clamped site and the possible dislodging of plaque within the clamped vessel wall. As mentioned above, the arterial bypass may be required due to the deposits of plaque which have occluded the vessel. However, the plaque is typically present throughout the artery and is not limited to the occluded location. Clamping the artery creates a risk of plaque being released into the blood stream. This release of plaque has the potential of causing a stroke, occlusion of a smaller peripheral vessel, or other vascular trauma. In a beating heart procedure, full clamping (i.e., cross clamping) of the aorta for graft attachment at the proximal anastomosis is not feasible. Therefore a side biting clamp is used to clamp off only a portion of the cross-section of the aorta, where the proximal anastomosis is performed. This type of clamping procedure poses the same risks described above with regard to cross clamping, e.g., the risk of release of plaque and resultant cause of a stroke, occlusion of a smaller peripheral vessel, or other vascular trauma.
Second, the blood flow may be diverted by the use of a balloon catheter within the aorta, such as described in U.S. Pat. No. 5,868,702, for example. Drawbacks of using a balloon catheter in creating a seal to divert blood flow include the possibility of disturbing plaque deposits and creating particles in the blood stream, the chance that the balloon catheter may move within the aorta disrupting the seal and resulting in blood loss, and trauma to aortic tissue caused by the pressure needed to create the seal.
PCT Patent WO 98/52475 to Nobles et al. attempts to address problems associated with diverting the blood flow. Nobles et al. provides a method and device for creating an area of hemostasis within a blood vessel without interrupting the flow of blood through the vessel which eliminates the need to clamp the vessel. However, the Nobles et al. device requires the withdrawal of the hemostasis device prior to obtaining a tight seal between the graft and vessel. Therefore, since the area of hemostasis is lost upon the retrieval of the hemostasis device, the artery is open and blood is lost until the sutures are tightened.
Yet another problem related to CABG procedure lies in the procedure of suturing the vessels to create a tight seal. To ensure the integrity and patency of the anastomosis, the graft and vessel to be joined must be precisely aligned with respect to each other. If one of the tissues is affixed too close to its edge, the suture can tear through the tissue and impair both the tissue and the anastomosis. Another problem is that, even after proper alignment of the tissue, it is difficult and time consuming to pass the needle through the tissues, form the knot with the suture material, and ensure that the suture material does not become entangled. These difficulties are exacerbated by the small size of the artery and graft. Another factor contributing to the difficulty of the CABG procedure is the limited time available to complete the procedure. The surgeon must complete the graft in as little time possible due to the absence of blood flowing through the artery. If blood flow is not promptly restored, sometimes in as little as 30 minutes, the tissues the artery supplies may experience significant damage or necrosis. As mentioned above, surgeons are under pressure to reduce the cross-clamp time, yet, an incomplete suture may result in a leak in the tissue approximation between the vessel and graft. Moreover, the tissue approximation must be smooth and open. Hence, the suture cannot be hastily performed.
Additionally, the difficulty of suturing a graft to an artery using minimally invasive surgical techniques, where the surgeon uses ports to access the internal organs to perform the procedure, has effectively prevented the safe use of complicated suturing technology in cardiovascular surgical procedures. Accordingly, many procedures are performed invasively and require a stemotomy, an opening of the sternum. As a result, the recovery times for patients is significantly increased. U.S. Pat. No. 5,868,763 to Spence et al. attempts to circumvent the suturing process by attaching the vessels to a cuff device. Spence et al. utilizes a passageway for continued blood flow so there is no clamping of the artery.
Houser et al., in U.S. Pat. No. 5,989,276, discloses various devices and techniques for performing bypass, one of which includes a device which can be intralumenally originated. Various other clamping arrangements are provided for securing a graft to a vessel without the use of sutures or other fasteners.
All of the problems discussed above are multiplied in those cases where a multiple anastomosis is required. In those cases where multiple bypass procedures are performed, the patient will naturally be subject to increased risks as multiple grafts must be sutured to perform the bypass.
There remains a need for improved anastomosis systems.
SUMMARY OF THE INVENTIONThe present invention involves apparatus and methods for connecting tissue. This invention may, for example, be used to secure one vessel to another, such as in a vascular anastomosis while maintaining blood flow within the vessel.
According to one aspect of the invention, an anastomosis apparatus is provided comprising a tubular member having an end with an edge adapted to form an opening in a vessel wall and an anchor member, which comprises a flexible shaft and a piercing member, slidably coupled to the tubular member. Preferably, a generally circular centering disk with a plurality of spikes is also provided to slide down along the flexible shaft of the anchor member.
During the surgery, a physician pushes the shaft of the anchor member to insert the piercing member through the vessel wall. The piercing member is then pulled back against the vessel wall. Once the piercing member is in place against the inner wall of the vessel, the centering disk is put in place and pushed against the outer wall of the vessel, thereby clamping the vessel wall between the centering disk and the piercing member. The tubular member is then moved over the shaft, centered by the disk and rotated to cut an opening through the vessel wall. Thereafter, the piercing member is used to coordinate with the centering disk to retain and retrieve the tissue cut by the tubular member. Next, an occlusion member is advanced within the tubular member through the opening in the vessel wall in order to substantially occlude such opening and form an area of hemostasis. The tubular member can then be retrieved, leaving the occlusion member in place, after which a graft is slid down along the occlusion member shaft for creating an anastomosis with the vessel.
According to one embodiment, the occlusion member comprises a cannula. According to another embodiment, the occlusion member comprises a radially expandable member, which can be an expandable brush-like member, an umbrella, a flexible cup or an inflatable balloon.
According to another aspect of the invention a cannula having an end portion adapted to pierce through a vessel is provided. The cannula may be passed through a vessel wall and a graft secured to the vessel adjacent to the cannula to facilitate an anastomosis without clamping the vessel, thereby avoiding the risk of dislodgement of plaque from the inner wall of the vessel which is incurred with clamping.
According to another aspect of the invention, a trocar adapted to receive the cannula and allow it to pivot is provided. The cannula, thus, may be repositioned to pierce the vessel wall at different locations and perform multiple anastomoses without relocation of the trocar in the vessel wall.
According to another aspect of the invention, a surgical fastener or clip cartridge is provided. One or more surgical fasteners may be loaded in the cartridge with ends of each fastener selectively releasable from the cartridge to anchor in either the graft or vessel to which the graft is to be attached. According to one cartridge embodiment, first and second tubular members are slidably coupled to one another and at least one surgical fastener placed therein with one end of the fastener engaging the first tubular member and another end of the fastener engaging the second tubular member.
According to yet another aspect of the invention, a dual-stage release fastener is provided which includes a clip movable between an open and a closed configuration and having a memory biased to the closed configuration. A first mechanical restraint is coupled to a first portion of the clip and is adapted to bias the first portion toward the open configuration. A second mechanical restraint is coupled to a second portion of the clip and is adapted to bias the second portion toward the open configuration.
The first and second mechanical restraints may be independently manipulatable to allow independent closure of the first and second portions of the clip.
According to still another aspect of the invention, an anastomosis apparatus is provided comprising a tubular member having an end with an edge adapted to form an opening in a vessel wall and an anchor member, which comprises a flexible shaft and a piercing member, slidably coupled to the tubular member. Preferably, a generally circular centering disk with a plurality of spikes is also provided to slide down along the flexible shaft of the anchor member. An adapter is mounted on the tubular member that forms the opening. The adapter includes wells in which needles are held in a predetermined orientation adapted for piercing through the vessel wall from the inside out, upon passing the adapter into the vessel and then pulling it back to perform the piercing action. Two-stage release fasteners may be used in conjunction with the adapter so as to affix the fasteners to the vessel after piercing it with the needles and then fixing the fasteners to a graft in a later operation.
The above is a brief description of some advantages of the present invention and deficiencies in the prior art. Other features, advantages, and embodiments of the invention will be apparent to those skilled in the art from the following description, accompanying drawings, and claims.
The present invention generally involves methods and apparatus for performing an anastomosis and may be used, for example, in bypass procedures. As used herein, the term graft includes any of the following: hemografts, autologous grafts, xenografts, allografts, alloplastic materials, and combinations of the foregoing.
Referring to
According to one aspect of the invention, a cannula having a distal portion adapted to pierce at least one wall portion of a vessel and a proximal portion is provided. The cannula may be used, for example, to create an area of hemostasis within the vessel and facilitate an anastomosis while allowing blood to flow through the vessel. In a preferred method, the cannula is passed through a vessel wall from the interior to the exterior of the vessel to create a hemostasis area within the cannula and within the vessel hole created thereby, as will be described in more detail below.
Referring to
The cannula may be introduced endovascularly or passed through a vessel wall to position it within a vessel. In the latter case, a trocar may be used. According to another aspect of the invention, a trocar having a varying diameter lumen may be used to allow the angular position of the cannula to be changed. Referring to
Referring to
According to another aspect of the invention, a surgical fastener or clip cartridge or retainer is provided and may be used with any cannula described above to make an anastomosis. Referring to
Referring to
Referring to
Rod (610), which extends through the cannula proximal portion and out from its other end, is pulled to unlock and allow release of other ends of the fasteners (
According to another aspect of the invention as shown in
The shaft (707) may be formed from medically acceptable polymers, stainless steel or Nitinol, for example and is flexible, yet stiff enough to have sufficient column strength to push the piercing member through the vessel wall. For normal CABG surgery, the tubular punch (704) preferably has an inner diameter between about 3.0-6.0 mm and a wall thickness between about 0.150-0.200 mm.
Whether barbed, umbrella-like, or some other expanding configuration, the piercing member (708) is tapered, and preferably pointed, in its “pre-entry” configuration, in order to pierce the vessel wall (
Once piercing member (708) has pierced the wall of vessel (714) and the operator has either rotated the shaft (707) (barbed configuration) or expanded the piercing member and pulled it back against the inner wall of the vessel (714) (umbrella-like or other expanding configuration), a generally circular centering disk (720) may be slid down along the flexible shaft (707), as shown in
The centering disk (720) may also function to keep the flexible shaft (707) at the center of the tubular punch (704) and coordinate with the piercing member to retain and retrieve the tissue cut (734), as shown in
With regard to the operation procedure, after the physician pushes the shaft to insert the piercing member (708) through the vessel wall, and after the piercing member is deployed (when using an umbrella-type actuator), or the barb type piercing member has been rotated, he or she will twist the punch (704) to create an opening in the vessel wall. Thereafter, the severed tissue (734) is held in place between the piercing member (708) and the centering disk (720), and retrieved through the inner lumen of the punch.
After the retrieval of the severed tissue (734), an occlusion device is inserted in order to prevent blood loss through the opening in the vessel wall. The occlusion device comprises two coaxial cylinders (726, 727) as shown in
For normal CABG surgery, the outer diameters of the inner and outer cylinders are less than about 3 mm and about 6 mm respectively. Preferably, the inner cylinder comprises polymer (polethylenes, polyurethanes, polyamides, polypropylenes) or other acceptable preferred materials, or stainless steel) materials such that it is flexible enough to allow side-to-side movement, and yet has sufficient column strength for the physician to push or pull it through.
Disk (720) may have a friction feature or ratchet (e.g., like a tie wrap) or some type of self-locking mechanism against shaft (707) to frictionally engage or otherwise resist backwards movement of the disk along the shaft. Thus, once the disk is engaged against the tissue of the vessel wall, it sandwiches the tissue cut (734), in cooperation with the piercing member on the opposite side of the vessel wall.
According to one embodiment of the occlusion device illustrated in
Referring to
As shown in
Once an area of hemostasis is created with the bristles (702) in place, a graft (712) is brought down over the outer cylinder (726) in place to form an anastomosis (
After the anastomosis is formed, the outer cylinder (726) is brought down over the bristles (702) to force them back into a compressed state within the outer cylinder (
One embodiment of the bristles (702) comprises deformable wires made from a shape memory alloy. A nickel titanium (Nitinol) based alloy may be used, for example. The Nitinol may include additional elements which affect the yield strength or the temperature at which particular pseudoelastic or shape transformation characteristics occur. The shape memory alloy preferably exhibits pseudoelastic (e.g., superelastic) behavior when deformed at a temperature slightly above its transformation temperature. At least a portion of the shape memory alloy is converted from its austenitic phase to its martensitic phase when the wire is in its deformed configuration.. As the stress is removed, the material undergoes a martensitic to austenitic conversion and springs back to its original undeformed configuration.
When the bristles are positioned within the outer cylinder (726) in their deformed configuration, a stress is present to maintain the bristles tightly therein. In order for the pseudoelastic bristles to retain sufficient compression force in their undeformed configuration, the bristles should not be stressed past their yield point in their deformed configuration to allow complete recovery of the bristles to their undeformed configuration. It is to be understood that the bristles may comprise other materials as well. Depending upon the size of the vessel and the graft, the length of the bristles extending from the distal end of the inner cylinder (727) can range from about 5 mm to about 20 mm.
According to another embodiment of the occlusion device as shown in
After the opening in the vessel wall is created, the anchor member (708) and the optional centering disk (720) are withdrawn from the vessel along with the severed tissue. The physician then inserts through the punch the occlusion member which comprises two generally coaxial cylinders (726, 727) and the membrane (800) in a deflated state. When the membrane (800) is at least substantially within the vessel (
Each of the fasteners used with this embodiment of the occlusion device has two needles (722, 725), one at each end. The fasteners are removably attached to the membrane and inserted into the vessel together with the membrane. The fasteners (721) can be glued to the membrane or attached to the membrane through a mechanical fitting such as a sliding or snap fit made of an acceptable material which may be mounted or insert molded into the membrane.
Each fastener is so removably attached to the membrane that only one needle (722) remains inside the vessel after the membrane (800) is inflated. As the membrane is slightly pulled back by the physician, the needle inside the vessel pierces through the vessel wall. Such needle (722) is then pulled completely out of the vessel. As the needle (722) is being so pulled, it causes the fastener to separate from the membrane and moves the suture (723) and the memory coil (721) along with it (
Referring to
As shown in
Referring to
Release mechanism members (121) have tapered ends (126), which are configured for positioning between coil (26) and fastener wire (34) as shown in
Flexible member (19) is threaded through channel (134) and between tapered member (3′) and annular member (115). When coil (26) is in a compressed state as shown in
As shown in
When coil (26) is in its free state (with the wire in its undeformed configuration), loops of the coil are generally spaced from one another and do not exert any significant force on the wire (34). When the coil (26) is compressed (with the wire (34) in its deformed configuration), loops of the coil on the inner portion of the coil are squeezed together with a tight pitch so that the loops are contiguous with one another while loops on the outer portion of the coil are spaced from one another. This is due to the compressed inner arc length of coil (26) and the expanded outer arc length of the coil. The compression of the loops on the inner portion of coil (26) exerts a force on the inner side of wire (34) which forces the wire to spread open (i.e., tends to straighten the wire from its closed configuration to its open configuration).
According to a further aspect of the occlusion device as shown in
In order to facilitate the expansion of the sheath (850) with the membrane to occlude the opening in the vessel wall, the sheath (850) overlaps itself in a roll-up fashion, as shown in
After occlusion of the opening by the membrane (800) and the sheath (850), the punch (704) and the outer cylinder (726) can be withdrawn and a graft (712) is slid down (
The sheath (850) may be made of superelastic materials such as Nitinol or stainless steel, etc. as described above. Alternatively, the sheath may be made of polymeric materials, e.g., thin polycarbonate, polyurethane, etc. In order to facilitate the expansion of the sheath with the membrane, it is preferable that the sheath has a wall thickness of less than about 0.5 mm.
According to another further aspect of the occlusion device as illustrated in
Each expansion member is attached to its adjacent members by a membrane (860). The membrane is held to the expansion member by e.g., glue, sandwich construction or other equivalent known techniques. The expansion members are arranged in a radially projecting pattern from the distal end of the inner cylinder (726) so that they can expand outwardly and form an umbrella when they exit the outer cylinder (726) (
The membrane (860) can be made in any suitable material which can block flow of fluid, particularly blood, therethrough. In choosing the material for the membrane, factors such as strength, flexibility, or bonding to the expansion elements should be considered. For example, the membrane may comprise latex, silicone, PET, etc.
In another example of the present invention shown in
The adapter (740), on the other hand, is preferably made of biocompatible plastics, such as ABS, polyurethanes, polycarbonates, or other medically compatible and acceptable polymers, for ease and less expense in manufacturing, although the adapter (740) may also be formed of the same metals used in making the cutting member (704′). The adapter (740) has about the same outside diameter as the tube of the cutting member (704′), or if slightly larger in diameter, is tapered (742) so as to facilitate the insertability of the adapter through the opening in the vessel (714). The walls of the adapter (740) are provided with bores or wells (744) that are dimensioned to snugly hold needles (725′) therein. The wells (744) may be mechanically formed in the adapter (740) as by boring, melting, electrodischarge machining, etc., or may be molded in during the formation of the adapter, for example. The wells (744) are formed so as to fit closely enough with the needles (725′) so as to maintain the needles at the desired angular orientation with respect to the longitudinal axis of the adapter (740), but not so tight as to form an impediment to their removal by hand or with a hand tool at the appropriate time during the procedure. The adapter orients the needles at an angle of between about 10 and 45 degrees. In one preferred example, the angle is about 30 degrees.
After formation of the opening in the vessel (714) wall and removal of the tissue plug (734) using anchor member (728) and disk (720), as shown in
In this embodiment, the needles (725′) preferably, although not necessarily, differ from needles (721) in that the needles (125′) are preferably substantially straight, while needles (721) are preferably curved. Further, this embodiment preferably, although not necessarily, uses two-stage release fasteners (821) for sequentially fastening the anastomosis as further described below.
Turning to
Coils (724′) are substantially the same as any of the coils (724) or (26) described above with the exception of being shorter to allow serial placement of two coils (724′) on a single wire (825) to enable separate and independent actuation and closing of opposite sides of the fastener (721). Release mechanisms (28a), which are preferably, but not necessarily the same, are releasably coupled to the respective enlarged ends (36) at opposite ends of the wire (825), and are, in turn coupled to the needles (722) and (725) by flexible members (18) and (19) respectively. The release mechanisms (28a) in this embodiment are preferably cable type release mechanisms, as described in copending application Ser. No. 09/259,705 entitled “Tissue Connector Apparatus with Cable Release”, and as shown above in
Assembly of the fastener (821) into the open position as shown in
A first coil (724′) is next slid over the wire (825) and an end of the coil (724′) is abutted against or placed adjacent to the enlarged portion (36). Next, a first retainer (836) is slid over the wire (825) and abutted against the opposite end of the coil (724′), after which a second retainer (836) is slid over the wire and placed adjacent the first retainer (836). A second coil (724′) is then slid over the wire (825) and a first end is abutted against the second retainer (836), while the second end of the second coil (724′) is used to determine where the wire (825) is cut to length. Generally, the wire (825) is cut so that it extends far enough, so that once the enlarged portion is formed at the end, the first and second portions are symmetric.
After cutting to length, the second end of the wire (825) is formed into an enlarged portion (836), preferably by electrodischarge. A first release mechanism (28a) is next fitted over the first enlarged portion (36), preferably according to the techniques described in copending application Ser. No. 09/259,705 with regard to the cable release. The first retainer (836) is then slid against the coil (724′) to compress it to a position that forces the first side of the fastener into its open configuration. The first retainer (836) is then swedged at its location to maintain the first portion of the fastener in the open position. Although swedging is preferred, welding or other equivalent methods of fixation may also be used to fix the retainer in place.
Likewise, a second release mechanism (28a) is fitted over the second enlarged portion (36), and the second retainer (836) is then slid against the second coil (724′) to compress it to a position that forces the second side of the fastener into its open configuration. The second retainer (836) is then swedged at its location to maintain the second portion of the fastener in the open position, which results in the entire fastener (821) now being in its open position, as shown in
Actuation of the first release mechanism (28a) is by squeezing or compression of a portion of the mechanism, which causes it to open, thereby releasing the enlarged portion (36). This, in turn allows a re-expansion of the coil (724′) thereby relieving the opening stresses against the first portion of the wire (825), thereby allowing the memory set of the wire (825) (and the memory set of the coil (724′) when a double memory configuration is used) to return the first portion of the wire (825) to the closed or memory position, as shown in
Actuation of the second release mechanism (28a) is performed independently of the first release mechanism, and therefor allows an independent closing of the second portion of the fastener (821), as shown in
Returning to
Once the fasteners (821) have been fixed into the wall of the vessel (714), the flexible sealing member (900) is expanded to establish the occlusion by removing the restraining sheath (950) from its restraining position, as shown in
After removal of the tube cutter assembly, a graft (712) is positioned over the restraining sheath (950) and into position at the anastomosis site as shown in
After all of the fasteners (821) have been fully closed to complete the approximation and anastomosis of the vessel (714) and graft (712), the restraining sheath (950) is slid back down over the flexible sealing member (900) to compress it and surround it as shown in
The above is a detailed description of particular embodiments of the invention. It is recognized that departures from the disclosed embodiments may be made within the scope of the invention and that obvious modifications will occur to a person skilled in the art. The full scope of the invention is set out in the claims that follow and their equivalents. Accordingly, the claims and specification should not be construed to unduly narrow the full scope of protection to which the invention is entitled.
Claims
1. An anastomosis apparatus comprising:
- a tubular member having an end with an edge adapted to form an opening in a vessel wall; and
- an occlusion member slidably coupled to the tubular member and adapted to substantially occlude said opening in the vessel wall to form an area of hemostasis.
2. The anastomosis apparatus of claim 1 wherein the occlusion member is a cannula having a cross-section adapted to substantially occlude said opening in the vessel wall.
3. The anastomosis apparatus of claim 1 wherein the occlusion member comprises a first and a second generally coaxial cylinders, and a radially expandable member attached to a distal end of said first cylinder to substantially occlude said opening in the vessel wall, said first cylinder being slidably positioned within said second cylinder.
4. The anastomosis apparatus of claim 3 wherein the radially expandable member comprises a plurality of bristles extending from said distal end of said first cylinder, said bristles having memory shapes that flare outwardly from said distal end of said first cylinder.
5. The radially expandable member of claim 4 wherein the bristles comprise nickel-titanium alloy.
6. The radially expandable member of claim 4 wherein the lengths of the bristles are less than 20 mm.
7. The radially expandable member of claim 4 wherein the first cylinder is hollow and the bristles are glued, attached, or otherwise fixed to an inside wall of the first cylinder.
8. The radially expandable member of claim 4 wherein the bristles are restrained by a ring attached to said distal end of the first cylinder.
9. The occlusion member of claim 4 wherein the first cylinder has an outer diameter of less than 8 mm.
10. The occlusion member of claim 4 wherein the first cylinder comprises polymeric material and/or stainless steel or other metallic material.
11. The occlusion member of claim 4 wherein the second cylinder has an outer diameter of less than 15 mm.
12. The occlusion member of claim 4 wherein the second cylinder comprises polymeric material and/or stainless steel, or other metallic material.
13. The anastomosis apparatus of claim 3 wherein the radially expandable member comprises a radially expandable membrane.
14. The radially expandable member of claim 13 further comprising a plurality of fasteners removably attached to the membrane, said fasteners being adapted to attach a graft to the vessel wall.
15. The radially expandable member of claim 14 wherein the fasteners are removably attached to the membrane by glue.
16. The radially expandable member of claim 14 wherein the fasteners are mechanically removably attached to the membrane.
17. The radially expandable member of claim 13 wherein the membrane comprises materials selected from the group consisting of: polyethylene terephthalate, polyethylene and polyurethane.
18. The radially expandable member of claim 13 further comprising a generally cylindrical sheath located coaxially outside the membrane, said sheath being radially expandable with the membrane.
19. The radially expandable member of claim 18 wherein the sheath comprises nickel-titanium alloy.
20. The radially expandable member of claim 18 wherein the sheath comprises polymeric materials.
21. The radially expandable member of claim 18 wherein the sheath has a wall thickness of less than about 0.5 mm.
22. The radially expandable member of claim 18 wherein the sheath overlaps itself in a roll-up fashion.
23. The anastomosis apparatus of claim 3 wherein the radially expandable member comprises a plurality of expansion members attached to said distal end of said first cylinder, said expansion members supporting a membrane therebetween and being foldable from an expanded position to a collapsed position.
24. The radially expandable member of claim 23 wherein the expansion members form a substantially convex surface in said expanded position.
25. The radially expandable member of claim 23 wherein the membrane is dimensioned to block the flow of blood through the opening in the vessel wall.
26. The radially expandable member of claim 23 wherein the expansion members comprise superelastic or shape memory materials.
27. The radially expandable member of claim 23 wherein the membrane comprises a medically compatible polymer.
28. The anastomosis apparatus of claim 3 wherein the radially expandable member comprises a membrane attached to said distal end of said first cylinder, said membrane being radially expandable from a collapsed position to an expanded position.
29. The radially expandable member of claim 30 wherein the membrane forms a substantially convex surface in said expanded position.
30. The radially expandable member of claim 30 wherein the membrane is dimensioned to block the flow of blood through the opening in the vessel wall.
31. The radially expandable member of claim 30 wherein the membrane comprises materials selected from the group consisting of polyethylene terephthalate, polyethylene and polyurethane.
32. The anastomosis apparatus of claim 1, further comprising an adapter coaxially mounted to said tubular member and adapted to pass said occlusion member therethrough.
33. The anastomosis apparatus of claim 32, said adapter further comprising wells adapted to hold needles in a predetermined orientation.
34. The anastomosis apparatus of claim 32, further comprising needles mounted in wells in said adapter, said wells holding said needles in an orientation adapted to pierce a vessel wall from the inside out.
35. The anastomosis apparatus of claim 34, further comprising fasteners connected with said needles, respectively, said fasteners being adapted to fix a graft to a vessel.
36. The anastomosis apparatus of claim 35, each of said fasteners comprising a clip movable between an open and a closed configuration and having a memory biased to said closed configuration, said clip having a first portion including a first end portion and a second portion including a second end portion; a first mechanical restraint coupled to said first portion of said clip and adapted to bias said first portion toward said open configuration; and a second mechanical restraint coupled to said second portion of said clip and adapted to bias said second portion toward said open configuration.
37. The anastomosis apparatus of claim 36, each of said fasteners further comprising a first release mechanism releasably fixed to said first end portion and adapted to release the bias of said first mechanical restraint against said first portion upon release from said first end portion.
38. The anastomosis apparatus of claim 37, each of said fasteners further comprising a flexible member interconnecting one of said needles with said first release mechanism.
39. The anastomosis apparatus of claim 37, each of said fasteners further comprising a second release mechanism releasably fixed to said second end portion and adapted to release the bias of said second mechanical restraint against said second portion upon release from said second end portion.
40. The anastomosis apparatus of claim 39, each of said fasteners further comprising a second needle releasably fixed to said second release mechanism.
41. The anastomosis apparatus of claim 40, each of said fasteners further comprising a second flexible member interconnecting said second needle with said second release mechanism.
42. An anastomosis system comprising:
- a tubular member having an end with an edge adapted to form an opening in a vessel wall; and
- an occlusion member slidably coupled to the tubular member and adapted to substantially occlude said opening in the vessel wall to form an area of hemostasis.
43. The anastomosis system of claim 42 further comprising an anchor member adapted to hold said vessel wall in place while the tubular member is forming said opening in said vessel wall, said anchor member being slidably coupled to the tubular member.
44. The anastomosis system of claim 43 wherein the anchor member comprises a shaft and a piercing member extending from a distal end of said shaft, said piercing member being adapted to pierce the vessel wall.
45. The anchor member of claim 44 wherein said shaft comprises a flexible polymeric material.
46. The anchor member of claim 44 wherein the shaft has a diameter of less than 3 mm.
47. The anchor member of claim 44 wherein the piercing member has a tapered end.
48. The anchor member of claim 44 wherein the piercing member has a pointed end.
49. The anastomosis system of claim 43 further comprising a generally circular centering disk slidably movable along the piercing member.
50. The anastomosis system of claim 49 wherein the centering disk is made from a medically acceptable polymer.
51. The anastomosis system of claim 49 wherein said centering disk comprises ABS or polyurethane.
52. The anastomosis system of claim 49 wherein the centering disk comprises one or more spikes extending from a surface of the centering disk proximal of the vessel wall.
53. The centering disk of claim 52 wherein said one or more spikes comprise Nitinol.
54. The centering disk of claim 52 wherein said one or more spikes have lengths of less than about 5 mm.
55. A cannula comprising a body member forming a lumen and a piercing member extending from said body member, said piercing member having a generally cylindrical edge adapted to cut tissue and said piercing member forming a cavity adapted to receive the tissue.
56. The cannula of claim 55 wherein said cylindrical edge is pointed.
57. The cannula of claim 55 further including a rod extending through said lumen, said rod having a pointed member extending therefrom.
58. The cannula of claim 57 wherein said pointed member includes a portion adjacent to said cylindrical edge, said pointed head portion having diameter greater than the inner diameter of said cylindrical edge.
59. A trocar comprising a body having a proximal portion, a distal portion, and a passageway extending between said proximal and distal portions, said passageway changing in dimension along a longitudinal portion thereof.
60. The trocar of claim 59 further including a seal disposed within said passageway.
61. A surgical fastener cartridge comprising: a first tubular member; a second tubular member slidably coupled to said first tubular member; and at least one surgical fastener having one end engaging said first tubular member and a second end engaging said second tubular member.
62. The cartridge of claim 61 wherein said surgical fastener has first and second shapes and said tubular member bias said fastener to said second shape.
63. The cartridge of claim 62 including a rod disposed in said second cylindrical member and urging said second end of said fastener against said second tubular members.
64. A method for performing an anastomosis while maintaining blood flow within a vessel comprising:
- positioning a cannula so that it extends through a vessel wall;
- attaching a graft to the vessel wall adjacent to said cannula while said cannula extends through said vessel wall; and
- removing the cannula.
65. The method of claim 64 wherein the cannula is positioned in the vessel wall from the interior of the vessel.
66. A method for performing an anastomosis on a vessel wall while maintaining blood flow within the vessel comprising:
- forming an opening in the blood vessel;
- inserting an occluding member into the opening cut into the vessel, thereby occluding the opening; and
- anastomosing a graft to the vessel at the opening.
67. The method of claim 66, wherein said forming an opening comprises:
- piercing the vessel wall with an anchor member; and
- cutting the opening in the vessel wall around the anchor member with a cutting tool.
68. The method of claim 67, further comprising removing a tissue plug produced by said cutting, prior to said inserting an occluding member.
69. The method of claim 67, wherein said inserting comprises inserting the occluding member into the opening cut into the vessel while the cutting tool is still in the opening.
70. The method of claim 69, further comprising withdrawing the cutting tool to allow the occluding member to expand against the periphery of the opening, thereby occluding it.
71. The method of claim 70, further comprising placing a graft over the occluding member and in alignment with the opening, prior to said anastomosing.
72. The method of claim 67, further comprising sliding a generally circular centering disk along the anchor member onto the vessel wall, prior to said cutting, thereby clamping vessel wall tissue between the centering disk and an end portion of the anchoring member.
73. The method of claim 72, further comprising removing the tissue plug in a clamped configuration between the centering disk and anchoring member.
74. The method of claim 66, wherein said anastomosing comprises fastening walls of the graft and vessel together using fasteners.
75. The method of claim 74, wherein said fastening is performed with self closing fasteners.
76. The method of claim 66, wherein the occluding member includes fasteners attached thereto, said method further comprising pulling back said occluding member slightly, after expanding to occlude, thereby piercing the vessel wall with needles attached to said fasteners.
77. The method of claim 76, further comprising grasping the needles and pulling them entirely through the vessel wall, thereby positioning the fasteners for performing the anastomosis and separating them from the occluding member.
78. The method of claim 77, wherein the fasteners each have a second needle at an end opposite the location of the needles used to pierce the vessel wall, said anastomosing further comprising piercing the graft with the second needles and securing the graft and the vessel together by closing the fasteners upon them.
79. The method of claim 67, wherein an adapter is mounted on the cutting tool, the adapter retaining a plurality of needles therein which are propositioned for piercing the vessel from the inside out, said method further comprising inserting the cutting tool and adapter into the vessel, prior to said inserting an occluding member, so as to position the needles against the inner wall of the vessel, and pulling back the adapter and cutting tool slightly to pierce the vessel wall with the needles; grasping the needles and pulling them all the way through the vessel and thereby also removing them from the adapter.
80. The method of claim 79, wherein the needles are connected to two-stage release fasteners having independently closable first and second portions, the needles being connected by flexible members to respective first portions of the fasteners, said method further comprising removing the needles and flexible members from the fasteners, after insertion of the occluding member, thereby closing the first portions of the fasteners and fixing the fasteners to the wall of the vessel.
81. The method of claim 80, wherein the fasteners each have a second needle connected to an end portion of the second portion thereof by a second flexible member, said anastomosing further comprising piercing the graft with the second needles and securing the graft and the vessel together by removing the second needles and second flexible members from the second portions of the fasteners, thereby closing the second portions of the fasteners on the graft and fixing the walls of the vessel and the graft in approximation.
82. An occlusion device comprising first and a second generally coaxial cylinders, the first cylinder being slidably positioned within the second cylinder and having a plurality of bristles extending from a distal end of said first cylinder, said bristles having memory shapes that flare outwardly from said distal end of the first cylinder.
83. The occlusion device of claim 82, wherein the bristles are made of super-elastic materials comprising nickel-titanium alloy.
84. The occlusion device of claim 82, wherein the lengths of the bristles extending from the distal end of the first cylinder are of less than about 5 mm.
85. The occlusion device of claim 82, wherein the bristles are fixed to the inside wall of the first cylinder.
86. The occlusion device of claim 82, wherein the bristles are restrained by a ring attached to the distal end of the first cylinder.
87. The occlusion device of claim 82, wherein the first cylinder has an outer diameter of less than about 3 mm.
88. The occlusion device of claim 82, wherein the first cylinder has a wall thickness of less than about 0.5 mm.
89. The occlusion device of claim 82, wherein the first cylinder comprises a medically compatible polymeric material.
90. The occlusion device of claim 82, wherein the second cylinder has a wall thickness of less than about 0.5 mm.
91. The occlusion device of claim 82, wherein the second cylinder comprises a medically compatible polymeric material.
92. An occlusion device comprising a radially expandable membrane and a plurality of fasteners removably attached to the membrane, said fasteners being adapted to attach a graft onto a vessel.
93. The occlusion device of claim 92, wherein the fasteners are attached to the membrane by glue.
94. The occlusion device of claim 92, wherein the fasteners are attached to the membrane through a mechanical fitting mechanism.
95. The occlusion device of claim 92, wherein the membrane comprises a medically compatible polymer.
96. An occlusion device comprises a radially expandable membrane and a generally cylindrical sheath located coaxially outside the membrane, said sheath being radially expandable with the membrane.
97. The occlusion device of claim 96, wherein the sheath comprises nickel-titanium alloy.
98. The occlusion device of claim 96, wherein the sheath comprises at least one polymeric material.
99. The occlusion device of claim 96, wherein the sheath has a wall thickness of less than about 0.5 mm.
100. The occlusion device of claim 96, wherein the sheath overlaps itself in a roll-up fashion, the overlap being greater in the unexpanded configuration and lesser in an expanded configuration.
101. An occlusion device comprising first and a second generally coaxial cylinders and a plurality of expansion members attached to a distal end of the first cylinder, said expansion members supporting a membrane therebetween and being foldable from a collapsed position and an expanded position, and said first cylinder being slidably positioned within said second cylinder.
102. The occlusion device of claim 101, wherein the expansion members form a substantially convex surface in said expanded position.
103. The occlusion device of claim 101, wherein the membrane is dimensioned to block the flow of blood through an opening in a vessel wall.
104. The occlusion device of claim 101, wherein the expansion members comprise superelastic material.
105. The radially expandable member of claim 96 wherein the membrane comprises at least one medically compatible polymeric material.
106. An occlusion device comprising first and second generally coaxial cylinders, and a membrane attached to a distal end of said first cylinder, said membrane being radially expandable from a collapsed position to an expanded position.
107. The occlusion device of claim 102, wherein the membrane forms a substantially convex surface in said expanded position.
108. The occlusion device of claim 106, wherein the membrane is dimensioned to block the flow of blood through the opening in the vessel wall.
109. The occlusion device of claim 106, wherein the membrane comprises at least one material selected from the group consisting of polyethylene terephthalate, polyethylene and polyurethane.
110. An occlusion device comprising a radially expandable member expandable from a relatively compressed smaller external dimension to a radially expanded, relatively larger external dimension, said radially expanded member fixed to an end of an elongated member; and a cylindrical restrictor adapted to pass over said elongated member and said radially expandable member, thereby compressing said radially expandable member so that it assumes said relatively compressed smaller external dimension.
111. The occlusion device of claim 110, wherein said restrictor is adapted to slide off of said radially expandable member, thereby allowing said radially expandable member to expand.
112. A dual-stage release fastener comprising:
- a clip movable between an open and a closed configuration and having a memory biased to said closed configuration, said clip having a first portion including a first end portion and a second portion including a second end portion;
- a first mechanical restraint coupled to said first portion of said clip and adapted to bias said first portion toward said open configuration; and
- a second mechanical restraint coupled to said second portion of said clip and adapted to bias said second portion toward said open configuration.
113. The fastener of claim 112, wherein said first and second mechanical restraints are independently manipulatable to allow independent closure of said first and second portions of said clip.
114. The fastener of claim 112, further comprising an enlarged first end portion on said first portion and an enlarged second end portion on said second portion.
115. The fastener of claim 114, further comprising first and second retainers fixed on said clip and abutting said first and second mechanical restraints respectively.
116. The fastener of claim 115, further comprising first and second release mechanisms releasably fastened to said first and second enlarged end portions respectively, said release mechanisms being independently operable to close a respective first or second portion of said clip upon release from a respective first or second enlarged end portion.
117. The fastener of claim 116, further comprising a first needle fixed to said first release mechanism.
118. The fastener of claim 117, further comprising a flexible member interconnecting said first needle and said first release mechanism.
119. The fastener of claim 117, further comprising a second needle fixed to said second release mechanism.
120. The fastener of claim 119, further comprising a flexible member interconnecting said second needle and said second release mechanism.
121. The fastener of claim 112, wherein said first and second mechanical restraints comprise first and second coils surrounding at least a portion of said first and second portions of said clip, respectively.
122. The fastener of claim 121, wherein said first and second coils each comprise a memory biased to said closed configuration and a memory shape substantially conforming to a memory shape of said first and second portions of said clip, respectively.
Type: Application
Filed: Jul 3, 2012
Publication Date: Jan 3, 2013
Applicant: Medtronic, Inc. (Minneapolis, MN)
Inventors: Steve Golden (Menlo Park, CA), John Nguyen (San Jose, CA), Charles T. Maroney (Portola Valley, CA), Sid Gandionco (Fremont, CA), Laurent Schaller (Los Altos, CA), Liem Ho (Mountain View, CA)
Application Number: 13/540,805
International Classification: A61B 17/11 (20060101);