JP2004534552A - Distally narrowed vascular graft and method of using the same to make arterial-to-venous and arterial-to-arterial connections - Google Patents

Abstract

The graft (10) has a first end (20) adapted to be inserted into a blood-receiving vascular site and a second end (30) adapted to be attached to an arterial site. have. The implant (10) is preferably made of a material having a generally uniform thickness, the implant (10) forming a lumen (11) having the same shape as the outer surface of the implant (10). I have. In the implant (10), the distal end (20) forms an orifice (21) and the proximal end (30) forms an orifice (31). The portion of the lumen (11) formed by the portion (23), also referred to as the "stepped" or "tapered" portion, generally becomes progressively smaller in diameter from a longitudinal point adjacent the portion (40). I have.

Description

[0001]
Reference to related application
This application is filed on Nov. 1, 2000, US Provisional Application Ser. No. 60 / 224,392, filed Aug. 10, 2002, entitled "Arterial Grafts and Methods for Transplanting the Grafts." No. 09 / 704,083, filed Jun. 8, 2001, entitled "Arterial Grafts and Methods for Implanting Arterial Grafts," US Provisional Application No. 60 / 297,088, entitled "Trunched Vessel Grafts and Methods of Using Same", and "Arterial Grafts and Artificial Grafts," filed June 8, 2001. Related Provisional Application No. 60 / 297,226, entitled "Apparatuses Related thereto and Methods of Using Them," are hereby incorporated by reference in their entirety.
[0002]
Background of the Invention
The present invention relates to a vascular graft and a method for implanting the vascular graft. The present invention is directed, in various respects, to a vascular graft having a stepwise tapered end, a vascular graft having a cuff-like structure (cuff) to assist in attaching the vascular graft to a target vessel, an end. The present invention relates to a connector device for making a connection between a part and an end and a method related thereto. In various embodiments of the invention, the vascular graft is used to form a connection between an artery and a vein (referred to herein as a vascular graft) or to form a connection between an artery and an artery. be able to.
[0003]
It has been reported that about 4000 new patients start hemodialysis per year as a background for vascular grafts used to make arterial and venous connections. This number continues to increase at a rate of about 10 percent. The creation and maintenance of hemodialysis access was reported in 1998 to have increased physician and hospital costs to approximately $ 8 billion. The term "access" refers to a location in the patient's circulatory system that is specially configured to serve as a site for supplying blood to the dialyzer and receiving blood returning from the dialyzer. If the condition of the patient allows, the preferred mode of access is to repeat the needle to move blood into and out of the dialyzer during the dialysis procedure, each in fluid communication with the patient's circulatory system. An implant or fistula, which is a subcutaneous device that can be inserted.
[0004]
The most common cause of dialysis patients admitted to the hospital is from access-related problems, and the frustration of access failures rises until a solution to the current access question is identified and implemented. It is expected to continue. Even in view of this high need, no significant progress has been made in access for hemodialysis in the last 30 years. Hakim and Himmelfarb describe in their paper entitled "Hemodialysis Access Failure: A Call to Action" that we no longer have the same thing as far as [Hemodialysis] access is concerned. (In fact, very little) that the same method cannot be continued and that the lives of our [end-stage renal disease] patients will be better and that the cost of access medicine will be reduced ("Hemodialysis Access Failure: A Call to Action", Kidney International, Vol. 54, (199). Year), 1029 through 1040 pages). If access patency could be doubled, $ 100 million could be saved annually and then directed to transplant programs or kidney disease treatment. In addition, dialysis patients, especially those with end-stage renal disease ("ESRD"), will then be able to enjoy a richer, healthier, and happier life.
[0005]
Arteriovenous fistula (AVF) is the preferred and most cost-effective long-term access for hemodialysis patients. AVF is an artificial direct connection between arteries and veins. When a large amount of blood flows through this connection, the veins become very large and thicker walls are formed more similar to arteries. Thus, AVF provides a large blood flow site to access the circulatory system for performing hemodialysis. For dialysis, two needles with large holes (typically 14 to 16 gauge) are placed through the skin of the dialysis patient into the AVF, one at the "arterial" end. The other is inserted so as to be located at the "vein" side end. When the tips of the needles are properly positioned inside the access, a stream of blood enters the end of the tube attached to each needle. Prior to initiating the dialysis treatment, the cap is removed from each tube, thereby allowing blood to fill the tubes, and then a saline syringe is infused through each tube. The two needles are then connected with rubber tubing to the inflow line (artery) and outflow line (vein) of the dialyzer.
[0006]
Unfortunately, even with careful screening and / or using Doppler ultrasound or venography to identify the appropriate vein, about 40-50% of patients are sufficiently small to form AVF. Does not have vascular tissue. In addition, many dialysis veterans who have previously failed to use AVF can no longer be considered suitable candidates for fistula formation.
[0007]
The next option for long-term access is placement of an arterial graft ("AVG"). AVG is an elongated plastic tube, usually made of porous polytetrafluoroethylene ("PTFE"), placed under the skin by a surgical procedure to fluidly connect arteries and veins. Once the implant is in place, the dialysis machine fluidly enters the patient's circulatory system by inserting a needle into the graft and connecting the needle to the dialysis machine by the tubing described above in connection with the AVF. Can be connected. However, the term "long term access" is incorrectly referred to when discussing AVG. Because reported patency rates are extremely low, annual patency rates of only 40% are often reported. Even in graft monitoring and active prophylactic treatment to prevent thrombus, primary and secondary patency rates remain low, and the additional cost incurred may also be unduly high.
[0008]
Although many factors play a role in the limited durability of PTFE grafts, the first harm is neointimal formation (NIH) with venous anastomosis stenosis and subsequent graft thrombosis. Is a progressive occurrence of A thrombosed implant can surgically or percutaneously remove the clot, or can use a sophisticated atherosclerotic device, angioplasty or vasodilation procedure, but NIH Will probably still recur. Remodeling of the implant by more proximal anastomoses can also be completed, but this has proven to be extremely prone to failure.
[0009]
Neointima formation is caused by a number of factors, including, for example, vascular endothelial injury due to growth factor release, turbulence at the anastomosis site, forces from anastomotic vibration, shear forces, uremia and other hypothetical etiologies. it is conceivable that. Numerous studies have shown sustained and steady growth of NIH at the site of venous anastomosis.
[0010]
The physician typically states that the diameter of the graft is gradually increasing and stepped and tapered along a portion or the entire length of the graft from the arterial end to the venous end. Graded and tapered implants have been used that terminate at the venous end with a hole in the portion with the largest diameter. An example of a tapered graft with a continuously increasing diameter is shown in FIG. 1 in which the diameter of the venous end 1 is greater than the diameter of the arterial end 2. large.
[0011]
The general belief widely believed among medical professionals is that the growth of NIH can be prevented or delayed by further increasing the size of the venous anastomosis. In an attempt to improve the durability of AVG, "hooded implants" with larger venous anastomoses have been utilized. A representative example of a prior art hooded implant (Venaflo, Impra Company) is shown in FIG. 2, in which the venous end 3 has a "hood" configuration. However, no major improvements resulting from the use of such a hooded implant have been reported. Indeed, Venaflo grafts were found to occlude earlier in some cases than standard graded grafts. In addition, attempts to retrieve the graft by surgical or non-surgical thrombectomy have proven to be more difficult than placing the graft and have a relatively short secondary patency rate. It has been found to bring.
[0012]
A graft is used to divert blood from one artery to another by fluidly connecting two arteries or to fluidly connect the end of a graft to a single artery at two different locations. If so, similar difficulties can arise. Such grafts can be used, for example, if a portion of the artery is clogged or damaged, or if it becomes necessary and desirable to divert blood flow to the portion of the artery due to other impaired blood flow or for other reasons. Can be used. However, the placement of an arterial bypass graft disrupts the natural blood flow in the artery, and is therefore also associated with neointimal formation (NIH), terminal anastomotic stenosis, and subsequent thrombosis of the graft.
[0013]
In view of the above, there is a great need for alternative treatment modalities, care for hemodialysis patients and care for other patients in need of placement of vascular grafts, such as arterial bypass grafts. In particular, there is a great need for new vascular access grafts and new arterial bypass grafts and methods for surgically installing them. The present invention fulfills these needs.
[0014]
Summary of the Invention
SUMMARY OF THE INVENTION The present invention provides a new graft and a method for surgical placement of the graft, thereby reducing the problems associated with hemodialysis access grafts and other vascular grafts known in the art. Solve. Embodiments of the present invention have various superior features.
[0015]
One form of the present invention is a unique vascular graft having a gradually tapering end. The distal portion has a substantially constant diameter portion which is adjacent to the stepped portion, which is then replaced by a relatively large diameter portion. Adjacent. This stepped portion decreases in diameter in the direction of blood flow through the implant, ie, toward the distal end. Alternatively, the graduated portion of decreasing diameter can extend from a relatively large diameter adjacent portion to the distal end. This step may vary in length and slope and may provide a substantially linear diameter reduction or a non-linear diameter reduction. Another form of the invention is a vascular graft, also having a stepped proximal end. In certain embodiments, the implants of the present invention may, for example, facilitate radiological identification and placement of subsequent implants, thereby facilitating implant monitoring or intervening treatment. Contains externally detectable labels, such as transmissive labels.
[0016]
Another form is a unique vascular graft having a cuff-like structure positioned a pre-selected distance from the distal end for attachment to a target vessel wall. This cuff-like structure forms a groove for receiving a purse string suture in the vessel wall. The cuff-like structure can be fixed to the outer surface of the implant as a single unit or can include multiple units. In one embodiment, the cuff-like structure includes two ring portions spaced apart from each other on the outer periphery of the implant at a preselected location to provide a groove therebetween for receiving the suture and the vessel wall. Contains. In another embodiment, at least a portion of the cuff-like structure, e.g., one or both of the rings, facilitates subsequent identification and placement of the anastomosis site, thereby requiring a graft. To facilitate surveillance or intervening treatment, an externally detectable marker, such as a radiopaque marker, is included.
[0017]
Another aspect of the invention includes a method for implanting a vascular graft, the method comprising making an incision in a wall of a target blood vessel and cutting the distal end of the graft of the invention. Inserting into the blood vessel such that the terminus is positioned downstream of the incision site and securing the graft to the wall of the blood vessel. In embodiments using an implant provided with a cuff-like structure, the securing step includes forming a purse string suture that engages a groove in the cuff-like structure. In certain embodiments, the method also includes removing the intermediate portion of the implant to shorten the implant. For example, the middle portion of the implant may be cut at two predetermined locations separated from each other by a distance equal to the length desired to be removed to provide two cut ends and connect the cut ends together. Thus, a shortened implant can be provided.
[0018]
In another embodiment of the present invention, a connector device is provided that has an advantageous use in assisting in connecting the ends of a plurality of conduits such as, for example, blood vessels, grafts, and the like. . In an embodiment for connecting two conduits, the connector has a first section configured to be inserted at one end of the conduit and a second section configured to be inserted at the end of the other conduit. And the division. In certain embodiments, the device also includes an intermediate section for maintaining the cut ends in a spaced relationship.
[0019]
It is an object of the present invention to provide a novel vascular graft and a method of implanting the same that provides an alternative to the unsatisfactory grafts and methods of the prior art.
[0020]
It is another object of the present invention to provide a method and apparatus for shortening a vascular graft by removing an intermediate portion from the graft.
Further aspects, embodiments, objects, advantages, benefits, appearances and features of the present invention will become apparent from the drawings and detailed description.
[0021]
Description of the preferred embodiment
While the features of the invention are particularly pointed out in the claims, the manner in which the invention may be made and used, by reference to the following description, taken in conjunction with the accompanying drawings, which are a part of this application, I can understand better.
[0022]
For the purposes of promoting an understanding of the principles of the invention, reference will be made to preferred embodiments, and specific language will be used to describe the same. Nevertheless, it will be understood that these terms are not intended to limit the scope of the invention, and alternatives and further modifications of the invention as described herein and the invention Still other uses of the principles of the invention will normally occur to those skilled in the art to which the invention pertains.
[0023]
The present invention, in one aspect, provides a vascular graft organ that defines a lumen through which blood passes and includes a generally tubular conduit having a tapered or tapered end. provide. This end directs blood flow out of the incision site and provides a more laminar flow of blood from the end of the graft into the vein or artery, thereby reducing turbulence at the anastomotic site. And can be inserted into the target blood vessel through the incision site.
[0024]
Referring to FIG. 3, which illustrates one embodiment of the present invention, a graft 10 has a first end 20 (here, the "end" of the graft) adapted for insertion into a blood receiving vascular site. ) And a second end 30 (referred to herein as the “proximal” end of the graft) adapted to be attached to an artery site selected to supply blood to the graft. Has been). It is understood by those skilled in the art that blood flows in one direction through a vascular graft. As used herein, the terms "proximal" and "distal" are used consistently to identify the end of the graft relative to the direction of blood flow within the graft. As these terms are used herein, blood flow flows in a proximal to distal direction. In other words, blood passes from the arterial site into the proximal end of the graft, and then flows through the graft toward the distal end of the graft, e.g., a vein where the proximal end is fluidly coupled, a secondary Flows into blood-receiving vessels, such as a normal artery or a location downstream of the same artery.
[0025]
Implant 10 is generally made of a material having a uniform thickness, so that implant 10 defines a lumen 11 having substantially the same shape as the outer surface of the implant. In the implant 10, the distal end 20 defines an orifice 21 and the proximal end 30 defines an orifice 31. The implant lumen portion formed by orifice 21 and portion 22 of implant 10 has a substantially constant diameter less than the diameter of the implant lumen portion formed by orifice 31 and portion 40 of implant 10. have. Also, the portion of the implant lumen 11 defined by the portion 23, referred to herein as a "stepped" portion or "tapered" portion, is also described herein. The diameter gradually decreases from a longitudinal point adjacent to the portion 40 to a longitudinal point adjacent to the portion 22, as described as a continuous taper.
[0026]
In one embodiment, the portion of the implant lumen 11 defined by the portion 40 has a diameter that is at least about 20% greater than the lumen portion defined by the portion 22. . In another embodiment, the portion of graft lumen 11 defined by portion 40 has a diameter that is at least about 40% greater than the portion defined by portion 22. In another embodiment, the portion of the implant lumen 11 defined by the portion 40 has a diameter that is at least about 50% greater than the portion defined by the portion 22. .
[0027]
In one embodiment, the portion of the lumen 11 defined by the portion 22 has an inner diameter of about 6 millimeters or less. In another embodiment, the portion of the lumen 11 defined by the portion 22 has an inner diameter of no more than about 5 millimeters. In another embodiment, the portion of lumen 11 defined by portion 22 has an inner diameter of about 3 millimeters to about 6 millimeters, and the lumen defined by portion 40. Section 11 has an inner diameter of about 4 to about 8 millimeters. In another embodiment, the portion of lumen 11 defined by portion 22 has an inner diameter of about 3.5 to about 4.5 millimeters and is defined by portion 40. The portion of the lumen 11 that is present has an inner diameter of about 5.5 to about 7.0 millimeters.
[0028]
In one embodiment, portion 23 extends over a relatively short length of implant 10, such as, for example, less than about 2 centimeters. In such an embodiment, portion 23 is preferably located about 1 cm to about 10 cm from distal end 20. In another embodiment, portion 23 is located about 1 cm to about 8 cm from distal end 20, and in yet another embodiment, portion 23 is It is located from 20 to about 1 cm to about 6 cm. In another embodiment, portion 23 extends over a longer length of the implant, for example, greater than about 2 centimeters, providing a slower taper. In one embodiment, portion 23 extends along the length of the implant from about 1 centimeter to about 10 centimeters.
[0029]
In another embodiment shown in FIG. 4, the implant 110 does not have a portion corresponding to the portion 22 in FIG. Up to a generally continuous taper. In one embodiment, portion 123 extends along a longitudinal axis of implant 10 from a longitudinal point at least about 2 cm from distal end 120. In another embodiment, portion 123 extends from a longitudinal point at least about 4 cm from distal end 120. In another embodiment, portion 123 extends from a longitudinal point about 2 cm to about 15 cm from distal end 120. In another embodiment, portion 123 extends from the distal end 120 from about 4 cm to about 15 cm longitudinally. In another embodiment, portion 123 extends from a longitudinal point about 2 cm to about 10 cm from distal end 120. In another embodiment, portion 123 extends from a longitudinal point about 4 cm to about 10 cm from distal end 120.
[0030]
Referring to FIG. 5, in another embodiment of the present invention, in addition to having a stepped-down distal portion, the implant 210 also includes a stepped-down proximal end. It also has a part. The graft 210 has a first end 220 adapted to be inserted into a blood receiving site and a second end adapted to be attached to an arterial site selected to supply blood to the graft. 230. In the implant 210, the distal end 220 defines an orifice 221 and the proximal end 230 defines an orifice 231. Orifice 221 and the portion of the implant lumen defined by portion 222 of implant 210 have a generally constant diameter less than the diameter of the portion of the implant lumen defined by portion 240 of implant 210 have. Further, the orifice 231 and the portion of the implant lumen defined by the portion 232 of the implant 210 are generally constant and smaller than the diameter of the portion of the implant lumen defined by the portion 240 of the implant 210. It has a diameter. The portion of the implant lumen 211 defined by the portion 223, also referred to herein as a “stepped” or “tapered” portion, is a portion from a longitudinal point adjacent the portion 240. The diameter gradually decreases to a longitudinal point adjacent to 222, which is also described herein as a continuous taper. Similarly, the portion of the implant lumen 211 defined by the portion 233 is a longitudinal portion adjacent to the portion 232, also referred to herein as a "stepped" or "tapered" portion. It has a generally smoothly increasing diameter from a point in the direction to a point in the longitudinal direction adjacent to the portion 240.
[0031]
In one embodiment, the portion of the implant lumen 211 defined by the portion 240 has a diameter that is at least about 20% greater than the lumen portion defined by the portion 222 or 232. are doing. In another embodiment, the portion of the implant lumen 211 defined by the portion 240 has a diameter that is at least about 30% greater than the portion defined by the portion 222 or the portion 232. are doing. In another embodiment, the portion of the implant lumen 211 defined by portion 240 has a diameter that is at least about 40% greater than the portion defined by portion 222 or portion 232. are doing. In another embodiment, the portion of the implant lumen 211 defined by the portion 240 has a diameter that is at least about 50% greater than the portion defined by the portion 222 or the portion 232. are doing. In another embodiment, the portion of the implant lumen 211 defined by the portion 240 has a length that is at least about 50% of the length of the implant. In another embodiment, the portion of the implant lumen 211 defined by the portion 240 has a length that is at least about 60% of the length of the implant. In another embodiment, the portion of the implant lumen 211 defined by the portion 240 has a length that is at least about 70% of the length of the implant. In another embodiment, the portion of the implant lumen 211 defined by the portion 240 has a length that is at least about 80% of the length of the implant. In another embodiment, the portion of the implant lumen 211 defined by the portion 240 has a length that is at least about 90% of the length of the implant. In another embodiment, the portion of the implant lumen 211 defined by the portion 240 has a length that is at least about 95% of the length of the implant.
[0032]
In one embodiment, the portion of lumen 211 defined by portion 222 has an inner diameter of no more than about 6 millimeters. In another embodiment, the portion of the lumen 211 defined by the portion 222 has an inner diameter of no more than about 5 millimeters. In another embodiment, the portion of the lumen 211 defined by the portion 232 has an inner diameter of about 6 millimeters or less. In another embodiment, the portion of lumen 211 defined by portion 232 has an inner diameter of no more than about 5 millimeters. In another embodiment, the portion of the lumen 211 defined by one or both of the portion 222 and the portion 232 has an inner diameter of about 3.5 to about 6 millimeters and the portion 240 The portion of the lumen 211 defined by has an inner diameter of about 4 to about 8 millimeters. In another embodiment, the portion of the lumen 211 defined by one or both of the portion 222 and the portion 232 has an inner diameter of about 3.5 to about 4.5 millimeters; The portion of the lumen 211 defined by the portion 240 has an inner diameter of about 5.5 to about 7.5 millimeters. In another embodiment, the portion of the lumen 211 defined by one or both of the portion 222 and the portion 232 has an inner diameter of about 3.5 to about 4.5 millimeters; The portion of the lumen 211 defined by the portion 240 has an inner diameter of about 5.5 to about 6.5 millimeters. In another embodiment, the portion of lumen 211 defined by one or both of portion 222 and portion 232 has an inner diameter of about 4 millimeters and is defined by portion 240. The portion of the lumen 211 that is present has an inner diameter of about 6 millimeters.
[0033]
Portions 223 and 233 can each extend over a relatively short length of implant 210, such as, for example, less than about 2 centimeters. In such an embodiment, portion 223 is located about 1 cm to about 10 cm from end 220 and section 233 is located about 1 cm to about 10 cm from end 230. It is preferred to be located at In another embodiment, portion 223 is positioned about 1 cm to about 8 cm from distal end 220 and section 233 is positioned about 1 cm to about 8 cm from proximal end 230. It is located in meters. In yet another embodiment, portion 223 is located about 1 cm to about 6 cm from distal end 220 and section 233 is about 1 cm to about 6 cm from proximal end 230. It is located up to centimeters. It should be understood that portions 223 and 233 can be the same or different lengths. Alternatively, portions 223 and 233 can each extend along a longer length of the implant, for example, greater than about 2 centimeters, to provide a slower taper. In one embodiment, portions 223 and 233 each extend along a length of about 2 cm to about 10 cm of the implant.
[0034]
In another embodiment shown in FIG. 6, the implant 310 does not have portions corresponding to portions 222 and 232 in FIG. Rather, the tapered portion 323 is continuously tapered from the larger diameter portion 340 to the distal end 320, and the tapered portion 333 is larger than the larger diameter portion 340 from the proximal end 330. It is characterized in that the diameter generally increases continuously. One or both of the portions 323 and 333 preferably extend along the longitudinal axis of the implant 310 from each end 320 and 330 to a longitudinal point of at least about 2 centimeters. In another embodiment, one or both of portions 320 and 330 extend from each end 320 and 330 to a longitudinal point of at least about 4 centimeters. In another embodiment, one or both of portions 320 and 330 extend from each end 320 and 330 to a longitudinal point of about 2 centimeters to about 15 centimeters. In another embodiment, one or both of portions 320 and 330 extend from each end 320 and 330 to a longitudinal point of about 4 centimeters to about 15 centimeters. In another embodiment, one or both of portions 320 and 330 extend from each end 320 and 330 to a longitudinal point from about 2 centimeters to about 10 centimeters. In another embodiment, one or both of portions 320 and 330 extend from each end 320 and 330 to a longitudinal point of about 4 centimeters to about 10 centimeters.
[0035]
Although the implants described herein are preferably made of polytetrafluoroethylene ("PTFE"), the invention is not intended to be limited by the material from which the implant is made. Implants can be advantageously made of a wide range of currently known or later developed biocompatible materials that have acceptable physical properties such as flexibility.
[0036]
A method for surgically implanting the implant of the present invention is also provided by the present invention. To place a graft according to the present invention, an incision is made at a location selected to receive blood from the graft within the vessel, and the distal end of the graft is introduced into the vessel at this incision site, At a predetermined distance downstream from the incision, the graft is hermetically secured to the vessel wall at the incision site. FIG. 7 shows a representative structure of the graft relative to the target blood vessel after deployment, in which the distal end 360 of the graft 365 is positioned with respect to the direction of the natural flow of blood within the blood vessel 370. It is located in the target blood vessel 370 at a position downstream from the incision site 380.
[0037]
In one embodiment, attaching the distal portion of the graft of the present invention to a target vascular site comprises: (1) making an incision in the wall of the target blood vessel at a predetermined site; (2) a first end. Inserting the end of the graft of the present invention into the blood vessel through the incision, such that is passed to a point downstream of the incision; (3) securing the graft to the blood vessel at the incision site; 4) Anastomosis of the proximal end to a preselected artery site. In one embodiment, the distal end of the graft can be advantageously secured to the target vessel using purse string sutures. In one method of practicing the present invention, the purse string suture may be inserted into the wall of the target vessel prior to making the incision. In another embodiment, the insertion involves inserting the distal end of the implant of the present invention through the incision and into the blood vessel such that the distal end passes to a point at least about 1 cm downstream of the incision. Including. In another embodiment, the insertion is performed through the incision through the distal end of the graft of the present invention into the vessel such that the distal end passes to a point about 1 to about 4 centimeters downstream of the incision. Including inserting. In another embodiment, the insertion is made through the incision through the incision through the distal end of the implant of the present invention such that the distal end passes to a point about 1 to about 3 centimeters downstream of the incision. Including inserting. By inserting the end of the graft into the blood vessel, blood flow is diverted from the incision site, thus reducing the strong flow of blood at the anastomosis site.
[0038]
One advantage of the present invention is that the ends of the grafts of the present invention can be placed in blood receiving vessels having a wide range of sizes, including vessels that were previously considered unsuitable due to size restrictions. is there. In one method of practicing the invention, the blood receiving vessel at the target attachment site selected for the anastomosis has a diameter of about 1.5 centimeters or less. In another embodiment,
The selected blood receiving vessel at the target attachment site has a diameter from about 0.4 centimeters to about 1.5 centimeters. In another embodiment, the selected blood receiving vessel at the target attachment site has a diameter of about 1.4 centimeters or less. In another embodiment, the selected blood receiving vessel at the target attachment site has a diameter of about 1.3 centimeters or less. In another embodiment, the selected blood receiving vessel at the target attachment site has a diameter of about 2 centimeters or less. The present invention also contemplates that it can be used to place the implant of the present invention in a relatively large vessel, such as a vessel in the patient's leg. Thus, in another embodiment, the selected blood receiving vessel at the target attachment site has a diameter of about 3 centimeters or less.
[0039]
In another embodiment, the present invention relates to a method for placing a purse string suture at an incision site at a desired distance from a distal end of the implant and surgically deploying the implant to create a wound at the incision site. An implant is provided that includes a cuff-like structure adapted to isolate the attached endothelium from the intravascular portion of the anastomosis. In this regard, in one aspect of the invention, an implant includes a cuff-like structure secured to the outer surface of the implant and defining a groove configured to receive a purse string suture for anastomosis. Pieces are provided. The present invention has standard grafts, i.e., non-tapered and other grafts, as well as tapered or tapered ends. It should be understood that the use of such cuff-like structures in combination with the novel implants described herein is contemplated.
[0040]
In one embodiment, the cuff-like structure is such that the grooves lie on a plane that is generally perpendicular to the longitudinal axis of the implant. In this configuration, when the graft is sutured to the vessel wall, the graft will pass through the vessel wall at approximately a 90 degree angle to the vein. In another embodiment, the cuff-like structure is such that the grooves lie on a plane that is at an angle to the longitudinal axis of the implant, as shown in FIGS. It has a structure. In one preferred embodiment, the grooves lie in a plane that forms an angle of about 45 degrees with the longitudinal axis of the implant, but the present invention contemplates a wide range of angles.
[0041]
In one embodiment, the cuff-like structure includes a single structure forming a groove. For example, FIG. 8 shows a cuff-like structure 650 configured to attach to the outer surface of an implant. Cuff-like structure 650 defines a lumen 651 sized to engage the outer surface of the implant at a desired location. The cuff-like structure 650 also includes a first protrusion 652 and a second protrusion 653 extending around the cuff-like structure 650 and forming a groove 655 therebetween. I have. The cuff-like structure 650 can be attached to the implant at a desired location using a biocompatible adhesive or can be formed integrally with the implant.
[0042]
In another embodiment, the cuff-like structure includes two ring-like structures extending around the implant and defining a groove therebetween. Referring to FIGS. 9 and 10, the implants 410, 510 each include a cuff-like structure 450, 550 that is affixed or integrally molded to the outer surface of the implants 410, 510. The cuff-like structures 450, 550 each include two ring-like structures 452, 453, 552, 553, each of which is configured to receive a purse string suture for venous or arterial anastomosis. 455 and 555 are defined.
[0043]
In one embodiment, the groove is located at least about one centimeter from the distal end. In another embodiment, the groove is located about 1 cm to about 5 cm from the end. In another embodiment, the groove is located about 1 cm to about 3 cm from the end. The distance from the distal end affects the length of the existing graft remaining inside the target vessel after completion of the graft implantation process. In one embodiment, for example, the cuff-like structure is positioned such that the groove defined by the cuff-like structure is located about 1 to about 3 centimeters from the end of the implant. I have. In another embodiment, the cuff-like structure is such that the groove defined by the cuff-like structure is located about 1.5 to about 2.5 centimeters from the end of the implant. Are arranged as follows. In another embodiment in which the cuff-like structure as shown in FIGS. 9 and 10 includes two ring-like structures, one ring is about 1.75 centimeters from the end of the implant. And another ring is located about 2.25 centimeters from the distal end, forming a groove between them.
[0044]
In another embodiment of the invention, at least a portion of the implant is coated and / or impregnated with an anticoagulant. In one embodiment, the surface of the implant that comes into contact with blood is coated and / or impregnated with an anticoagulant. The presence of the anticoagulant on the surface of the implant has the beneficial effect of preventing blood in contact with the surface from clogging and / or adhering to the surface. In accordance with certain embodiments of the present invention, the surface to which the anticoagulant can be advantageously coated or impregnated includes the surface of the graft lumen, the distal portion to be inserted into the target blood receiving vessel. (I.e., for a graft having a cuff-like structure, the portion of the graft between the cuff-like structure and the distal end) and the presence of the cuff-like structure within the target vessel. There is an outer surface of the portion of the cuff-like structure to be placed within the cavity (ie, the portion of the cuff-like structure closest to the end of the implant). Suitable anticoagulants that can be used to coat and / or impregnate the surface of the implant include, for example, carbon, heparin and silicone.
[0045]
In another embodiment, at least a portion of the cuff-like structure includes an externally detectable sign, for example, a radiopaque sign. The presence of such a marker allows the location of the cuff-like structure to be ascertained using radiation or other means, thereby providing a relative position of the cuff-like structure on the implant. Based on this, it is possible to ascertain where the diameter of the implant has changed and / or where the implant is in the blood vessel. This confirmation facilitates post-installation monitoring or mid-treatment required by the implant. In certain preferred embodiments, one or both of the cuff-like structure protrusions or rings include an externally detectable marker. In another embodiment, one or both of the ends of the implant include an externally detectable marker, thereby externally locating one or more ends of the implant. The subsequent method is facilitated. In one preferred embodiment, the end of the vein is marked with an externally detectable sign.
[0046]
As used herein, the term "externally detectable" refers to a material that is used by medical imaging devices, including fluoroscopy, x-ray, CT, MRI, ultrasound, and other forms of remote imaging. Is intended to refer to a property of a material that can be imaged. A wide range of medical imaging devices are commercially available. The term "externally detectable" as used herein refers not only to radiopaque materials, but also to materials that can be detected by a medical imaging device due to different concentrations or other properties than the surrounding materials. Inclusive. For example, fluoroscopy can be used with radiopaque materials. The radiopaque material selected for use in accordance with the present invention can be, for example, a barium compound such as barium sulfate, for example, a metallic material such as tantalum, or other radiopaque material. Selecting an appropriate radiopaque material for use in conjunction with the present invention is well within the purview of those skilled in the art. Alternatively, MRI or ultrasonography can be used to detect materials that differ in concentration from substances in the human body and other surroundings.
[0047]
Externally detectable markers may be, for example, by incorporating an inert, externally detectable material into a paint or other coating applied to the cuff-like structure, or through a cuff-like structure or cuff-like structure. Externally in the polymer used to make the cuff-like structure or part of the cuff-like structure or part of the graft It can be provided by kneading possible materials.
[0048]
The present invention also provides, in certain aspects, a method for non-invasively monitoring a patient having a subcutaneous implant of the present invention. In one embodiment, the method uses X-ray or fluoroscopy imaging for radiopaque materials, or uses NRI or ultrasonic scanning for different concentrations of the material. Implanting the implant of the present invention, wherein the implant has a material that is detectable from a patient, and ascertaining the location and / or patency of the implant by examining the patient. .
[0049]
As described herein, a method of implanting an implant of the present invention having a cuff-like structure is also provided by the present invention. According to the present invention, in order to place a graft having a cuff-like structure, an incision is made in the target blood vessel, the end of the graft is introduced inside the blood vessel, and a groove is formed at the incision site in the blood vessel. Position the cuff-like structure so that it is positioned to receive the wall, and secure the vessel wall to the graft. An exemplary structure of a graft with a cuff-like structure relative to the target vessel after placement is illustrated in FIG. 11 in which the distal end 460 of the graft 465 is within the target vessel 470 and the blood flow within the vessel 470. Is positioned downstream of the incision site with respect to the natural flow of the incision. The cuff-like structure 480 is positioned such that the groove formed by the cuff-like structure receives the vessel wall at the incision site.
[0050]
In one embodiment, the anastomosis is performed such that (1) making an incision in the wall of the preselected target vessel and (2) the groove is positioned to receive the vessel wall and suture. Inserting the end of the graft with the cuff-like structure into the blood vessel through the incision, (3) fixing the wall to the cuff-like structure, and (4) preselecting the second end By anastomosis to the target artery site. In one embodiment, the distal end of the graft can be advantageously anchored to a blood receiving vascular site. In one method of practicing the present invention, a purse string suture may be inserted into the wall of the target vessel prior to making an incision, wherein the purse suturing is performed using the purse string suture to form a cuff-like structure in the vessel wall. Including sticking to. In addition to directing blood flow out of the incision site, reducing the force of the implant over the anastomosis site, and making the blood flow more laminar, the incision and The amount of damage to the endothelium of blood vessels created by suturing can also be significantly reduced. Furthermore, in accordance with the present invention, the creation of an anastomosis using a cuff-like structure and a purse string suture allows the incision itself (ie, the incisal edge of the vessel wall) to be isolated from the inside of the vessel. . Thus, blood in the graft and blood vessels does not come into contact with the incision site.
[0051]
It should be understood that the present invention also contemplates the use of cuff-like structures in combination with standard implants, i.e., non-tapered implants. Further, while embodiments including a cuff-like structure are described and shown herein, it is not intended that the present invention be limited to implants having a cuff-like structure, and the present invention is not limited thereto. Certain features, such as those described above, provide a structure that does not have a cuff-like structure. In the absence of a cuff-like structure, the graft can be anastomosed to a blood-receiving vessel using other techniques known in the art, and the graft can be implanted in a manner known in the art. Optionally, it can have an alternative structure for attachment to a blood vessel.
[0052]
Turning to another advantageous feature of the present invention, one of ordinary skill in the art can readily appreciate that placement of an implant generally includes modifications to the length of the implant being installed. For example, arteriovenous grafts are typically manufactured to have extra length that can be removed if needed. One reason for this extra length is to provide an implant that can be used for patients of all sizes. In addition, this provides the physician placing the implant with tolerance in selecting an appropriate subcutaneous route for the implant to extend from the target arterial site to the target venous site. Thus, during placement of an arteriovenous graft, a portion of the graft that is known to be redundant is typically removed by cutting an appropriate length from one end of the graft. In this regard, during placement of the arteriovenous graft, the graft can be passed subcutaneously from a point near the target venous anastomosis site to a point near the arterial anastomosis site (or vice versa). The extra length is then trimmed, if necessary, from one or both ends to provide an appropriately positioned end of the graft for attachment to each vessel. Similar techniques are commonly used in the art for installing arterial grafts.
[0053]
The process described above may be such that the implant being deployed has a particularly desirable configuration at each end, e.g., tapered or stepped ends and tapered, according to certain features of the invention. Obviously, it is not very suitable for an implant placement process in which an implant having a stepped or stepped proximal end is used. When placing an implant of this type, reducing the length of the implant by simply trimming a predetermined length from one end of the implant is typically unacceptable. Thus, to reduce the length of the implant, a predetermined length is cut from the intermediate portion of the implant, and then the two cut ends are joined in an end-to-end fashion to form a continuous It is necessary to provide an implant conduit. In addition to the above, if arteriovenous grafts, bypass grafts, etc., must be modified, it is also necessary to achieve an end-to-end connection between the two pieces of the graft. This type of modification generally involves making a connection between the ends of the implant pieces. However, suturing two pieces of PTFE together for a new or modified arteriovenous graft can lead to scarring and / or ingrowth at the connection site. Thus, suturing the grafts in an end-to-end fashion can lead to thrombosis or failure of the grafts, in significant excess cases. In addition, suturing the two ends of the PTFE can lead to significant bleeding at the anastomotic site, further increasing surgical time and cost.
[0054]
In another aspect of the present invention, there is provided a connector device that can find advantageous use in assisting in connecting the ends of the implant pieces. The connector device of the present invention may find a particularly advantageous application where it is desirable or necessary to reduce the length of the arteriovenous graft by removing the intermediate portion. In certain embodiments of the present invention, after the intermediate portion is removed, the two cut ends of the implant are connected using the connector device of the present invention. Of course, the present invention is not intended to be limited to the connection of the two severed ends of an arteriovenous catheter. The connector device of the present invention can be used to connect end portions.
[0055]
In one embodiment illustrated in FIG. 12, the connector 710 is generally tubular and, as shown in FIGS. 13 and 14, of a graft piece or other conduit 771, 772 being connected. A lumen 750 configured to be in fluid communication with the lumens 761, 762 is defined. The connector 710 includes a first end 720 configured to be inserted into an end 773 of a first graft piece or other conduit 771 and a second graft piece or other conduit. A second end 740 configured to be inserted into end 774 of 772 and a relatively large outer diameter configured to maintain the implant pieces 773, 774 in a spaced relationship. And an intermediate portion 730 having
[0056]
In other embodiments, connector 710 also includes means for attaching graft pieces 771, 772 to connector 710. In one embodiment, after the connector 710 is placed in contact with the graft pieces 771, 772, an adhesive formulation, for example, an adhesive compound may be applied to the first end 720 and the second end 720 to retain the connector. The outer surface with the second end 740 is provided. In another embodiment illustrated in FIG. 15, the first end 720 and the second end 740 each receive a fastening member, such as, for example, a clamp, clip, thread, etc. Grooves are formed. FIG. 16 shows a representative example of a connector 710 according to this embodiment connected to the graft pieces 771, 772 by threads 791, 792 positioned to engage the grooves 781, 782. In another embodiment illustrated in FIG. 17, one or both of the grooves are formed between protrusions or rings 783, 784, 785, 786 formed around sections 720 and / or 740. ing. It is understood, of course, that the projections or rings are configured to form grooves between them, but are large enough to make the above sections unacceptably difficult to insert into the end of the implant. Is preferably not present. In still another embodiment illustrated in FIG. 18, one or each of the first end 720 and the second end 740 engages a fastening member, such as, for example, a clamp, clip, thread, or the like. And a single protrusion or ring 788, 789 that is structured to be compliant. The connector of this embodiment inserts the sections 720 and 740 into the end of the implant such that the end of the implant extends over the protrusions 788 and 789, and then engages the selected fastener with the protrusion. Can be secured to the end of the implant by positioning the implant adjacent to the protrusion, thereby preventing the end of the implant from slipping from the end of the connector. It will of course be understood that the connector of the present invention can alternatively be attached to the implant piece in other ways as will occur to those skilled in the art.
[0057]
In another embodiment illustrated in FIG. 19, there is no intermediate section having a relatively large outer diameter, and the connector 710 is configured to be insertable into the end of the first conduit. 720 and a second section 740 configured for insertion into the end of the second conduit. The connector 710 has grooves 781 and 782 for receiving fastening members, such as, for example, clamps, clips, ties, and the like.
[0058]
The connector according to the invention is preferably made of a relatively rigid biomaterial. Although the robustness of the connector of the present invention can be varied, the connector will withstand the forces of the threads, clips, etc. used to handle, insert into the graft piece and secure the graft piece to the connector. Preferably, it is sufficiently robust. Of course, it is also important that the connector be robust enough to prevent bending or collapsing at the connection site. It is also important that the connector not be biologically degraded in the environment in which it is deployed. For example, connectors used to connect pieces of an arteriovenous or arterial bypass graft must be made of a suitable material that does not degrade in the presence of physiological blood. The selection of a suitable material is well within the purview of those skilled in the art, and a variety of suitable materials are commercially available.
[0059]
The connector of the present invention is preferably sized to slide fit within the end of the conduit being connected. The loose fit helps prevent the formation of spaces or voids between the connector and the end of each implant and helps secure the connector to the end of the implant. Thus, it will be appreciated that various sized connectors are preferred when selected for use in connecting various sized implants. In certain embodiments of the present invention as illustrated in FIG. 20, the connector 710 has a tapered end to facilitate insertion of the end of the connector into the end of each implant. Parts 721 and 741 are included. Of course, these ends are preferably not inclined to the extent that they cause substantial turbulence or obstruction in the flow of blood through the implant and the connector after placement of the connector. Choosing a tapered shape that will achieve the desired results of the present invention is well within the purview of those skilled in the art. Insertion of the connector of the invention into the end of the implant can also be facilitated, if necessary, by moistening the surface of the connector with saline to lubricate the connector prior to insertion. It will be appreciated that alternative biocompatible fluids may be used to moisten and / or lubricate the connector and that one skilled in the art may select a suitable fluid to achieve this purpose. It can be understood.
[0060]
It is anticipated that the connectors of the present invention will often be used to connect implant pieces of generally constant inner diameter. In one embodiment of the present invention, the outer diameter of the first end and the outer diameter of the second end are substantially the same. Many arteriovenous implants have an inner diameter of, for example, about 5 to about 8 mm. Thus, in one preferred embodiment, the inner diameter of the first end and the inner diameter of the second end are about 5 to 8 mm. It should be understood that the connector of the present invention can also be used to connect pieces of an implant or other conduit having different internal diameters. The connector used to connect such pieces would, of course, have a first end with a different outer diameter than the second end. In one preferred embodiment, the diameter of the first end and the diameter of the second end are each within about 0.5 mm of the inner diameter of the target implant piece.
[0061]
The connector device of the present invention need not form a straight lumen as shown in the drawings. Rather, in certain embodiments, the connector of the present invention is curved.
[0062]
Accordingly, in one embodiment of the present invention, (1) a distal end adapted to be positioned within a blood receiving vessel and defining a first orifice having a first diameter; A) a proximal end adapted for attachment to an arterial site; and (3) a lumen disposed between the distal end and the proximal end and having a generally constant second diameter greater than the first diameter. A first tubular portion defining a portion, and (4) a first tapered portion provided between the first tubular portion and the distal end, the first tapered portion being along the first tapered portion. A vascular graft is provided that includes a first tapered portion of decreasing diameter. In another embodiment, the implant is provided between the distal end and the first tapered portion and defines a lumen portion having a generally constant diameter corresponding to the first diameter. Includes two tubular sections.
[0063]
In yet another embodiment, the proximal end of the implant forms a second orifice having a third diameter smaller than the second diameter, the implant including the proximal end and the first tubular member. A second tapered portion having a substantially uniform increase in diameter between the portions. In yet another embodiment, the implant includes a third tubular portion between the proximal end and the second tapered portion, the third tubular portion generally corresponding to a third diameter. A lumen portion having a constant diameter is defined.
[0064]
In another embodiment, a cuff-like structure is secured to the outer surface of the implant at least about one centimeter from the distal end, the cuff-like structure providing a purse string suture for an anastomosis. A groove is formed that is structured to accept it. In yet another embodiment, the implant generally lies on a plane that is at about a 45 degree angle to the longitudinal axis of the implant. The cuff-like structure in one embodiment includes a tubular member defining a lumen sized to engage an outer surface of the implant, and a groove extending around and surrounding the tubular member. First and second projections. In another embodiment, the cuff-like structure includes a first ring member secured to the implant and a second ring member also secured to the implant; The first and second ring members form a groove between them.
[0065]
In other embodiments, the cuff-like structure or other portion of the implant includes an externally detectable marker. In certain embodiments, the externally detectable label is a radiopaque label, while in other embodiments, the externally detectable label differs from the concentration in the patient's body. Has a concentration. In certain embodiments, the cuff-like structure and other portions of the implant are coated with a paint or other coating formulation that includes an externally detectable substance.
[0066]
Another alternative form of the invention includes (1) making an incision in the wall of a preselected target vessel, (2) preparing a vascular graft according to the invention, and (3) distal end. Inserting the end of the graft from the incision into the blood vessel such that the gas passes to a point downstream of the incision; (4) securing the graft to the blood vessel; Anastomosing the end to a preselected target arterial site.
[0067]
In another form of the invention, the implant is secured to the vessel using a purse string suture. In another form of the invention, the purse string suture is inserted into the wall of the target vessel prior to making the incision. In yet another form of the invention, the inserting includes inserting the distal end from the incision into the blood vessel such that the distal end passes to a point at least about 1 cm downstream of the incision. In another embodiment of the present invention, the implant includes a cuff-like structure secured to the outer surface of the implant at least about one centimeter from the distal end, the cuff-like structure comprising: And a groove configured to receive a purse string suture for anastomosis. In this embodiment, the step of inserting includes inserting the distal end of the graft from the incision into the blood vessel such that the groove is positioned to receive the wall of the blood vessel, and the step of securing comprises: Fixing to a cuff-like structure. In yet another method of practicing the invention, a purse string suture is inserted into the wall of the target blood vessel before the incision is made, and the securing step includes pulling the purse string suture into the groove.
[0068]
In another embodiment of the present invention, (1) anastomosing a first end of a vascular graft to a first blood vessel, and (2) connecting a second end of the vascular graft to a first vessel. Anastomosis to two blood vessels; (3) removing the intermediate portion of the graft by cutting the graft at two locations between the first end and the second end; (4) A) a first end defining a lumen and adapted to be inserted into the lumen of the first graft piece, and inserted into the lumen of the second graft piece; Providing a generally tubular connector device having a second end configured to allow the first and second implant pieces to be connected to the first and second portions of the connector device. And connecting to the method. In certain embodiments, the connector device further includes an intermediate portion configured to maintain the ends of the implant pieces in a spaced relationship. In another embodiment, each of the first section and the second section has a groove for receiving a clip, clamp, tie, etc. for attaching the section to the first and second implant pieces. Alternatively, one or more rings are formed. In yet another embodiment, the first and second ends are coated with an adhesive formulation to attach the sections to the first and second implant pieces. In yet another embodiment, the connection comprises: (1) inserting the first portion into the lumen of the first graft piece; and (2) connecting the second portion to the second graft piece. Securing; (3) inserting the second portion into the lumen of the second graft piece; and (4) securing the second portion to the second graft piece. Achieved.
[0069]
In accordance with yet another aspect of the present invention, a first end defining a penetrating lumen and (1) structured for insertion into a lumen of a first graft piece. And (2) a second end configured to be inserted into the lumen of the second graft piece, and (3) a relative relationship in which the ends of the graft piece are spaced apart from each other. An intermediate section configured to maintain the first and second implant pieces, the first and second ends being coated with an adhesive formulation to attach the ends to the first and second implant pieces. A generally tubular connector device is provided.
[0070]
In accordance with yet another aspect, the invention includes a first end defining a penetrating lumen and (1) adapted to be inserted into the lumen of the first graft piece; (2) a second end configured to be insertable into a lumen of a second graft piece, wherein each of the first and second ends has the same first and second ends. A generally tubular connector device is provided that forms a groove or one or more rings for receiving clips, clamps, thread for binding, etc. for attachment to a second implant piece.
[0071]
In accordance with yet another aspect, the invention includes a first end defining a penetrating lumen and (1) adapted to be inserted into the lumen of the first graft piece; (2) a second end configured to be insertable into the lumen of the second graft piece; and (3) an end section of the graft piece maintained in a mutually spaced relative relationship. And a threaded clip for clamping the first and second ends to the first and second graft pieces. Provides a generally tubular connector device forming a groove or one or more rings for accommodating the like. In certain embodiments, the groove or ring is configured to receive a purse string suture.
[0072]
In certain embodiments, the lumen of the connector device is substantially straight. In other embodiments, the connectors are not straight.
As mentioned above, one advantage of the present invention is that the use of an implant having a tapered or stepwise tapered end allows the incision to be reduced in size. This is expected to reduce the amount of endothelial injury and mitigate the cascade leading to NIH. Further, in embodiments that include a cuff-like structure on the implant, an anastomosis with a purse string suture can remove a damaged endothelial layer from the intravascular portion of the anastomosis. The cuff-like structure may also prevent sliding or dislodging of the purse string suture which can have apparently inconsequential results. Reducing the diameter of the implant outlet also serves to reduce turbulence and make the flow more laminar.
[0073]
Although the distal taper will have an effect on the speed and pressure of blood flow within the implant of the present invention, the implant of the present invention exhibits excellent fluidity over time, while It is believed that other advantages will be apparent from the present description. Indeed, graft surveillance studies performed by researchers have reported that the majority of functioning AVGs have anastomotic or other stenosis greater than 50% of their original diameter. Other researchers have stated that "critical stenosis that causes thrombosis has a diameter reduction of about 70%" (Hakim and Himmerlfarb (1998)). In an implant of the present invention having a 4 millimeter end that tapers from a 6 millimeter section, the diameter is actually reduced by only 33% at the end. Further, in embodiments where each end (ie, distal and proximal) is tapered, the bulk flow through the implant is not significantly altered by having a gradually tapering distal end. Will.
[0074]
The resistance to flow provided by having a tapered end is expected to result in a slow flow rate within the portion of the larger diameter implant. Flows of over 800 ml per minute have been reported to be important in preventing thrombosis (Hakim and Himmerlfarb (1998)). For the reasons described above, it is believed that the implants of the present invention remain patent for an acceptable period of time, with adequate blood pressure and arterial inflow. Thrombus in the larger diameter portion of the implant of the present invention caused by reduced flow rate may be present, although there may be some possibilities that may be relevant to the use of the implant of the present invention. If so, the high likelihood of thrombosis can be resolved by using anticoagulants and / or antiplatelet substances.
[0075]
In addition, Lumsden suggests that the length of a segment having a diameter of 4 millimeters on a graded graft at an arterial anastomosis may adversely affect patency if it is greater than 2 centimeters. Said that you could not. This was consistent with Poiseuille's law and the findings of Hakim and Himmelfarb on flow rates, although the differences did not appear when statistically significant. Hagen Poiseuille's law
Q = ΠR ⁴ ΔP / 8ηL
When applying, if the other variables remain unchanged, as the radius (R) of the tube decreases, the flow (Q) also decreases. Lumsden's findings are expected to apply to the ends as well. Accordingly, one preferred embodiment of the present invention provides for a stepped tapered end having dimensions (ie, the radius and length of the stepped tapered portion) that do not significantly increase the risk of graft thrombosis. Contains. In one preferred embodiment, the tapered end portion has a length of about 3 centimeters or less. In another embodiment, the tapered end portion has a length of about 2 centimeters or less. In another embodiment, the tapered end portion has a length of about 1 centimeter or less.
[0076]
As noted above, a widespread idea and current trend is to implant a graft having a relatively large arterial anastomosis. It is believed that such ideas and trends stem from the perception that grafts with large venous anastomoses have delayed clogging of the distal graft. This is because a larger stenosis is needed to narrow the venous anastomosis beyond the critical size required for patency. One skilled in the art would not find any motivation in the prior art to use AVGs with smaller ends, and the skilled person concludes that a relatively small anastomosis leads to accelerated critical stenosis and clogging points. Will. Although the relatively small anastomosis by the classical method (end-to-side joining) leads to the development of NIH and more sudden "critical stenosis" due to thrombosis, the present invention A unique device and method is provided that allows for the placement of a narrowed or tapered end.
[0077]
All references, including publications, patents, and patent applications, cited or listed herein are specially incorporated as if each separate reference was incorporated by reference and incorporated in its entirety herein. And are incorporated by reference as individually indicated. Further, any theory, proposed actuation mechanism or discovery set forth herein is meant to further enhance the understanding of the invention, and the present invention is not intended to be limited to such theory, proposed actuation mechanism or discovery. It is by no means intended to be limited to While the invention has been illustrated and described in detail in the drawings and foregoing description, these are to be considered exemplary and not of a limiting nature; It is to be understood that all modifications, equivalents, and variations that fall within the spirit of the invention as defined are desired to be protected.
[Brief description of the drawings]
FIG.
1 shows a standard tapered implant according to the prior art, increasing in diameter from a proximal end 2 to a distal end 1.
FIG. 2
1 shows a hooded implant according to the prior art.
FIG. 3
1 is a side view of one embodiment of a vascular graft according to the present invention.
FIG. 4
FIG. 6 is a side view of another embodiment of a vascular graft according to the present invention.
FIG. 5
FIG. 6 is a side view of another embodiment of a vascular graft according to the present invention.
FIG. 6
FIG. 6 is a side view of another embodiment of a vascular graft according to the present invention.
FIG. 7
FIG. 2 is a partially broken side view of the implant of the present invention after implantation of the implant.
FIG. 8
FIG. 4 is a side view of an embodiment of a cuff-like structure according to the present invention.
FIG. 9
FIG. 6 is a side view of another embodiment of a vascular graft according to the present invention.
FIG. 10
FIG. 6 is a side view of another embodiment of a vascular graft according to the present invention.
FIG. 11
FIG. 2 is a partially broken side view of the implant of the present invention after implantation of the implant.
FIG.
1 is a perspective view of one embodiment of a connector device according to the present invention.
FIG. 13
FIG. 13 is a perspective view of the connector device of FIG. 12, also showing the implant being connected.
FIG. 14
FIG. 13 is a perspective view of the connector device of FIG. 12, showing the device positioned to connect two implants.
FIG.
FIG. 4 is a perspective view of another embodiment of the connector according to the present invention.
FIG.
FIG. 16 is a perspective view of the connector device of FIG. 15, showing a state in which it is being used for connection of an implant.
FIG.
FIG. 9 is a perspective view of another embodiment of the connector device according to the present invention.
FIG.
FIG. 9 is a perspective view of another embodiment of the connector device according to the present invention.
FIG.
FIG. 9 is a perspective view of another embodiment of the connector device according to the present invention.
FIG.
FIG. 9 is a perspective view of another embodiment of the connector device according to the present invention.
FIG. 21
FIG. 13 is a perspective view of the connector device of FIG. 12, shown positioned for connection of two grafts, and also showing the end of the positioned connected graft within a blood vessel.

Claims (64)

A vascular graft forming a lumen through which blood passes,
A distal end adapted to be placed in a blood receiving vessel through the wall of the blood vessel, the distal end forming a first orifice having a first diameter;
A proximal end that can be attached to an artery site;
A first tubular portion between a distal end and a proximal end, the first tubular portion forming a portion of a lumen having a second generally constant diameter larger than the first diameter;
A first tapered portion provided between the first tubular portion and the distal end, the first tapered portion having a generally gradually decreasing diameter along the first tapered portion. Including vascular grafts. The implant of claim 1, wherein:
The implant, wherein the second diameter is at least about 20% greater than the first diameter. The implant of claim 1, wherein:
The implant, wherein the second diameter is at least about 30% greater than the first diameter. The implant of claim 1, wherein:
The implant, wherein the first diameter is less than or equal to about 6 millimeters. The implant of claim 1, wherein:
The implant, wherein the first diameter is less than or equal to about 5 millimeters. The implant of claim 1, wherein:
The implant, wherein the first diameter is between about 3.5 and about 4.5 millimeters and the second diameter is between about 5.5 and about 7.0 millimeters. The implant of claim 1, wherein:
A second tubular portion between the distal end and the first tapered portion, the second tubular portion having a generally constant diameter corresponding to the first diameter; The implant forming the cavity. The implant according to claim 7,
The implant wherein the longitudinal length of the first tapered portion is less than about 2 centimeters. The implant according to claim 7,
The implant, wherein the first tapered portion is positioned about 1 to about 10 centimeters from the distal end to the distal end. The implant of claim 1, wherein:
The implant wherein the longitudinal length of the first tapered portion is about 2 to about 10 centimeters. The implant of claim 1, wherein:
The implant wherein the first tapered portion extends from the distal end to a longitudinal position of at least about 4 centimeters from the distal end. The implant of claim 1, wherein:
The implant, wherein the first tapered portion extends from a longitudinal location about 4 to about 15 centimeters from the distal end to the distal end. The implant of claim 1, wherein:
The proximal end forming a second orifice having a third diameter smaller than the second diameter, the implant further comprising a second orifice between the proximal end and the first tubular portion; An implant comprising a second tapered portion, the second tapered portion having a generally evenly increasing diameter. The implant according to claim 13,
A third tubular portion between the proximal end and the second tapered portion, the third tubular portion defining a portion of a lumen having a generally constant diameter corresponding to the third diameter; Forming graft. The implant of claim 14, wherein:
The implant, wherein the second diameter is at least about 20% greater than the third diameter. The implant of claim 14, wherein:
The implant, wherein the third diameter is less than or equal to about 6 millimeters. The implant of claim 14, wherein:
The first diameter is about 3.5 to about 4.5 millimeters, the second diameter is about 5.5 to about 6.5 millimeters, and the third diameter is about 3.5 to about 4 millimeters. The implant, which is .5 millimeters. The implant according to claim 13,
The implant wherein the first tubular portion has a length of at least about 60% of the length of the implant. The implant according to claim 13,
The implant, wherein the first tubular portion has a length that is at least about 70% of the length of the implant. The implant according to claim 13,
The implant, wherein the first tubular portion has a length of at least about 80% of the length of the implant. The implant according to claim 13,
The implant, wherein the first tubular portion has a length of at least about 95% of the length of the implant. The implant of claim 1, wherein:
The device further includes a cuff-like structure secured to an outer surface of the implant at least about one centimeter from the distal end, the cuff-like structure receiving a purse string suture of a vessel wall for anastomosis. An implant forming a structured groove. The implant of claim 22, wherein
The implant wherein the groove lies in a plane that forms an angle of about 45 degrees with the longitudinal axis of the implant. The implant of claim 22, wherein
An implant, wherein the cuff-like structure is positioned about 1 to about 10 centimeters from the end. The implant of claim 22, wherein
An implant, wherein the cuff-like structure is positioned about 1 to about 5 centimeters from the end. The implant of claim 22, wherein
The cuff-like structure,
A tubular member defining a lumen sized to engage an outer surface of the cuff-like structure;
A first and second protrusion extending around the tubular member and having a groove formed therebetween. The implant of claim 22, wherein
The cuff-like structure,
A first ring member fixed to the implant,
A second ring member secured to the implant;
An implant, wherein the first ring member and the second ring member form a groove therebetween. 28. The implant of claim 27,
The first ring member is positioned about 1.5 to about 2 centimeters from the distal end, and the second ring member is positioned about 2 to about 2.5 centimeters from the distal end. The graft is located in the. 28. The implant of claim 27,
The first ring member is positioned about 1.75 centimeters from the distal end, and the second ring member is positioned approximately 2.25 centimeters from the distal end; Graft. Forming an incision in the wall of the preselected target vessel;
Providing a vascular graft forming a lumen for blood to flow, comprising:
The vascular graft is
A distal end adapted to be placed within the vessel from the incision and forming a first orifice having a first diameter;
A proximal end adapted to be attached to an artery,
A first tubular portion disposed between the distal end and the proximal end, the first tubular portion forming a portion of the lumen of a second generally constant diameter greater than the first diameter; A tubular portion;
A first tapered portion between the first tubular portion and the distal end, the first tapered portion having a generally increasing diameter along the tapered portion. And
Inserting the distal end from the incision into the blood vessel such that the distal end passes to a point downstream of the incision;
Securing the graft to the wall of the blood vessel;
Anastomosing the proximal end of the implant to a preselected target arterial site. 31. The method of claim 30, wherein
The method wherein the implant is secured to a vessel wall using a purse string suture. 32. The method according to claim 31, wherein
The method wherein the purse string suture is inserted into the wall of a target blood vessel prior to making the incision. 31. The method of claim 30, wherein
The method wherein the insertion comprises inserting the end from the incision into a blood vessel such that the end passes to a location at least about 1 centimeter downstream of the incision. 31. The method of claim 30, wherein
The method, wherein the vessel has a diameter less than about 1.5 centimeters. 31. The method of claim 30, wherein
The method, wherein the blood vessel has a diameter no greater than about 1.4 centimeters. 31. The method of claim 30, wherein
The method, wherein the blood vessel has a diameter of about 1.3 centimeters or less. 31. The method of claim 30, wherein
The method, wherein the blood vessel has a diameter of about 3 centimeters or less. 31. The method of claim 30, wherein
The implant includes a cuff-like structure secured to an outer surface of the implant at least about one centimeter from the distal end, the cuff-like structure accommodating a purse string suture for an anastomosis. To form a groove with a structure that
The inserting includes inserting the end of the graft from the incision into a blood vessel such that the groove is positioned to receive a wall of the blood vessel;
The method wherein the securing comprises securing a vessel wall to the cuff-like structure. 39. The method according to claim 38, wherein
The method wherein the vessel wall is secured to the cuff-like structure using a purse string suture. The method of claim 39, wherein
The method wherein the purse string suture is inserted into the wall of the target vessel prior to forming the incision, and wherein the securing comprises retracting the purse string suture into the groove. The implant of claim 1, wherein:
An implant, wherein the implant comprises an externally detectable label. The implant of claim 1, wherein:
An implant, wherein the cuff-like structure includes an externally detectable marker. 42. The implant of claim 41,
The implant, wherein the externally detectable label is a radiopaque label. 42. The implant of claim 41,
The implant, wherein the externally detectable marker comprises a material having a concentration different from that of the human body. 42. The implant of claim 41,
The implant, wherein the externally detectable marker is a paint or a coating containing an externally detectable material. 42. The implant of claim 41,
An implant, wherein at least a portion of the cuff-like structure includes an externally detectable material. 31. The method of claim 30, wherein
The method, wherein the implant includes an externally detectable label. 39. The method according to claim 38, wherein
The method wherein the cuff-like structure includes an externally detectable marker. Anastomosing the first end of the vascular graft to the first blood vessel;
Anastomosing a second end of the graft to a second blood vessel;
Cutting the implant at two locations between the first end and the second end removes an intermediate portion of the implant, thereby removing the first end. Providing a first graft piece including the first graft piece and a second graft piece including the second end;
A generally tubular connector device having a lumen formed therein, wherein the first end section is configured to be insertable within the lumen of the first graft piece; Providing a tubular connector device having a second end section configured for insertion into the one-piece piece;
Connecting the first and second implant pieces to the first end section and the second end section of the connector device. 50. The method of claim 49, wherein
The method, wherein the connector device further comprises an intermediate section configured to maintain the ends of the implant pieces in a spaced relationship. 50. The method of claim 49, wherein
One or both of the first and second end sections form a groove for receiving a clip, clamp or tie for attachment to one or both of the first and second graft pieces. Is the way. 50. The method of claim 49, wherein
The method, wherein one or both of the first and second end sections are coated with an adhesive formulation for attaching to one or both of the first and second implant pieces. 50. The method of claim 49, wherein
One or both of the first and second end sections may have a clip, clamp, or groove therebetween for receiving a clip, clamp or tie for attachment to one or both of the first and second graft pieces. A method comprising two forming rings. 50. The method of claim 49, wherein
One or both of the first and second end sections include a ring for receiving a clip, clamp or tie for attaching to one or both of the first and second graft pieces. Is the way. 50. The method of claim 49, wherein
The method, wherein one or both of the first and second end sections form a tapered end. A method according to any one of claims 49 to 55, wherein
The connection is
Inserting the first end section into the lumen of the first graft piece;
Securing the first end section to the first graft piece;
Inserting the second end section into the lumen of the second graft piece;
Securing the second end section to the second graft piece. A generally tubular device forming a penetrated lumen,
A first end section configured to be insertable within the first graft piece;
A second end section configured to be insertable within the second graft piece;
An intermediate section configured to maintain the graft pieces in a spaced relative relationship. The apparatus according to claim 57, wherein
An apparatus wherein one or both of said first and second end sections are coated with an adhesive formulation to attach said sections to said first and second implant pieces. The apparatus according to claim 57, wherein
One or both of the first and second end sections form a groove for receiving a clip, clamp or tie for attachment to one or both of the first and second graft pieces. Equipment. The apparatus according to claim 57, wherein
One or both of the first and second end sections may intersperse a groove for receiving a clip, clamp or tie for attachment to one or both of the first and second graft pieces. The device, comprising two rings forming the device. The apparatus according to claim 57, wherein
One or both of the first and second end sections include a ring for receiving a clip, clamp or tie for attaching to one or both of the first and second graft pieces. You are the device. The apparatus according to claim 57, wherein
The device, wherein the first and second end sections form a tapered end. A generally tubular connector device defining a through lumen, wherein:
A first end section configured to be insertable into the lumen of the first graft piece;
A second end section configured to be insertable into the lumen of the second graft piece;
The device, wherein each of the first and second end sections defines a groove for receiving a suture for attaching the same to the first and second implant pieces. An apparatus according to any one of claims 57 to 63,
The device wherein the lumen of the connector device is substantially straight.

Images