Patent Application
20170128658
The present subject matter relates generally to arteriovenous access valve systems and, more particularly, to an arteriovenous access valve system including separate valve tubes and one or more tube connectors configured to couple the valve tubes together.
The function of kidneys, which are glandular organs located in the upper abdominal cavity of vertebrates, is to filter blood and remove waste products. Specifically, kidneys separate water and waste products of metabolism from blood and excrete them as urine through the bladder. Chronic renal failure is a disease of the kidney in which the kidney function breaks down and is no longer able to filter blood and remove waste substances. Should certain toxic waste substances not be removed from the blood, the toxic substances may increase to lethal concentrations within the body.
Hemodialysis is a life-sustaining treatment for patients who have renal failure. Hemodialysis is a process whereby the patient's blood is filtered and toxins are removed using an extracorporeal dialysis machine. For hemodialysis to be effective, large volumes of blood must be removed rapidly from the patient's body, passed through the dialysis machine, and returned to the patient. A number of operations have been developed to provide access to the circulation system of a patient such that patients may be connected to the dialysis machine.
For example, the most commonly performed hemodialysis access operation is a subcutaneous placement of an arteriovenous graft, which is made from a biocompatible tube. The biocompatible tube can be made of, for instance, a fluoropolymer such as polytetrafluoroethylene. One end of the tube is connected to an artery while the other end is connected to a vein. The arteriovenous graft is typically placed either in the leg or arm of a patient.
Blood flows from the artery, through the graft and into the vein. To connect the patient to a dialysis machine, two large hypodermic needles are inserted through the skin and into the graft. Blood is removed from the patient through one needle, circulated through the dialysis machine, and returned to the patient through the second needle. Typically, patients undergo hemodialysis approximately four hours a day, three days a week.
Various problems, however, have been experienced with the use of an arteriovenous graft. For example, arterial steal occurs when excessive blood flow through the arteriovenous graft “steals” blood from the distal arterial bed. Arterial steal can prevent the proper supply of blood from reaching the extremities of a patient.
To address such problems, systems and processes have been deployed which can minimize or prevent complications by closing the arteriovenous graft when hemodialysis is not taking place. An example of one such system is described in U.S. Pat. No. 7,025,741 entitled “Arteriovenous Access Valve System and Process”, which is hereby incorporated by reference herein in its entirety for all purposes. These systems and processes utilize two separate valve assemblies, such as balloon valve assemblies, to force closure of an arteriovenous graft by pressing the opposite ends of the arteriovenous graft walls together.
However, such valve systems currently require that the two valve assemblies be surgically connected to a conventional arteriovenous graft via end-to-end anastomoses after such valve assemblies have already been anastomosed to the artery and the vein of the patient. As a result, current valve systems require a total of four anastomoses (e.g., around 60-80 stiches), which significantly impacts the overall length of the surgery required to implant such conventional valve systems. Moreover, the requirement of four separate anastomoses can make the corresponding surgery quite tedious
Accordingly, an improved valve system that reduces the surgery time and/or tedious nature of implanting the system within a patient would be welcomed in the technology.
Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
In one aspect, the present subject matter is directed to an arteriovenous access valve system. The system may generally include a first valve tube extending lengthwise between an arterial end and a first joint end, with the first valve tube including a first valve device. The system may also include a separate second valve tube extending lengthwise between a venous end and a second joint end, with the second valve tube including a second valve device. In addition, the system may include at least one tube connector coupled between the first and second valve tubes.
In another aspect, the present subject matter is directed to an arteriovenous access valve system. The system may generally include a first valve tube extending lengthwise between an arterial end and a first joint end, with the first valve tube including a first valve device and a first tube portion extending outwardly from the first valve device towards the first joint end. The system may also include a separate second valve tube extending lengthwise between a venous end and a second joint end, with the second valve tube including a second valve device and a second tube portion extending outwardly from the second valve device towards the second joint end. In addition, the system may include a tube connector extending lengthwise between a first end and a second end. The first joint end of the first valve tube may be configured to be coupled to the tube connector at or adjacent to the first end and the second joint end of the second valve tube may be configured to be coupled to the tube connector at or adjacent to the second end.
In a further aspect, the present subject matter is directed to an arteriovenous access valve system. The system may generally include a first valve tube extending lengthwise between an arterial end and a first joint end, with the first valve tube including a first valve device. The system may also include a separate second valve tube extending lengthwise between a venous end and a second joint end, with the second valve tube including a second valve device. In addition, the system may include a graft and first and second tube connectors, with the graft extending lengthwise between a first graft end and a second graft end. The first tube connector may be configured to couple the first joint end of the first valve tube to the first graft end of the graft and the second tube connector may be configured to couple the second end of the graft to the second joint end of the second valve tube.
In yet another aspect, the present subject matter is directed to a method for providing access between an artery and a vein of a patient. The method may generally include subcutaneously implanting an arteriovenous access valve system in the patient. The arteriovenous access valve system may include a first valve tube extending lengthwise between an arterial end and a first joint end and a separate second valve tube extending lengthwise between a venous end and a second joint end. The first valve tube may include a first valve device and the second valve tube may include a second valve device. The arteriovenous access valve system may also include at least one tube connector configured to be coupled between the first and second valve tubes. In addition, the method may include opening the first and second valve devices to allow blood to flow through the first and second valve tubes between the artery and the vein of the patient and closing the first and second valve devices to prevent blood from flowing through the first and second valve tubes between the artery and the vein of the patient.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:
Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
In general, the present subject matter is directed to an arteriovenous access valve system including separate valve tubes configured to be coupled together to form a continuous flow path between an artery and a vein of a patient. Specifically, in several embodiments, the system may include a first valve tube extending between an arterial end and a first joint end, with the arterial end being configured to be coupled to the patient's artery. In addition, the system may include a separate, second valve tube extending between a venous end and a second joint end, with the venous end configured to be coupled to the patient's vein. Each valve tube may also include a valve device integrated therein or otherwise associated therewith. For instance, the first valve tube may include a first valve device disposed at or adjacent to its arterial end. Similarly, the second valve tube may include a second valve device disposed at or adjacent to its venous end. The first and second valve devices may generally be configured to be actuated between an opened position and a closed position to allow or prevent blood flow through the valve tubes, respectively.
Moreover, the system may also include one or more tube connectors configured to couple the separate valve tubes together. For instance, as will be described below, in one embodiment, the system may include a single tube connector extending lengthwise between a first end and a second end, with the first end being configured to be coupled to the first joint end of the first valve tube (e.g., via one or more loop stiches) and the second end being configured to be coupled to the second joint end of the second valve tube (e.g., via one or more loop stiches). As a result, the tube connector may serve as a direct fluid coupling between the first and second valve tubes to allow a continuous flow path to be defined between the patient's artery and vein. In another embodiment, the system may include first and second tube connectors configured to couple the separate vale tubes together via a graft. For instance, the first tube connector may be coupled between the first valve tube and one end of the graft and the second tube connector may be coupled between the second valve tube and the opposed end of the graft. As such, the tube connectors may serve as fluid couplings between the first and second valve tubes and the graft to allow a continuous flow path to be defined between the patient's artery and vein.
It should be appreciated that the disclosed arteriovenous access valve system may generally provide numerous advantages over conventional systems. For example, as opposed to the four anastomoses required by traditional systems, the disclosed system only requires two anastomoses, one to couple the arterial end of the first valve tube to the patient's artery and another to couple the venous end of the second valve tube to the patient's vein. Such a reduction in the number of anastomoses significantly reduces the amount of surgery time required to implant the components of the disclosed system into a patient as well as reduces the overall complexity of the surgical procedure.
In addition, the disclosed system components may be adjustable to meet the needs of the patient. Specifically, in embodiments in which the separate valve tubes are configured to be coupled together via a common connector, the length of each valve tube may be adjusted, as is necessary or desired, prior to connecting the tubes to one another. For example, each valve tube may be cut to the desired length required to suit the specific patient's body size, vascular system, access type and/or access location (e.g., the patient's arm versus the patient's thigh). The cut ends of the valve tubes may then be attached to the tube connector to fluidly couple the first valve tube to the second valve tube. Similarly, in embodiments in which the valve tubes are configured to be coupled together via separate tube connectors and a graft, the length of each valve tube and/or the length of the graft may be adjusted, as is necessary or desired, to customize the system components to the patient.
Referring now to
Referring now to
In order to carry out hemodialysis, a first hypodermic needle 116 may be inserted through the skin and into either the first valve tube 102 or the second valve tube 104. Blood is removed from the flowpath formed by the first and second valve tubes 102, 104 through the needle 116 and into a dialysis machine 118. In the dialysis machine 118, waste materials are removed from the blood. After circulating through the dialysis machine 118, the blood is then fed back into the flowpath defined by the first and second valve tubes 102, 104 via a second hypodermic needle 120 at a location downstream of the first hypodermic needle 116.
In the illustrated embodiment, the first hypodermic needle 116 is shown as being inserted into the first valve tube 102 and the second hypodermic needle 120 is shown as being inserted into the second valve tube 104. However, in other embodiments, the first and second hypodermic needles 116, 120 may be both inserted into the first valve tube 102 or the second valve tube 104.
In addition, the first and second valve tubes 102, 104 may each include a valve device 122, 124 integrated therein and/or otherwise associated therewith. For example, as shown in
In several embodiments, the valve devices 122, 124 may correspond to balloon-actuated valves and, thus, may each include an inflatable balloon (not shown in
It should be appreciated that, the actuator assembly 126 may generally correspond to any suitable device(s) or component(s) that is configured to actuate or adjust the valve devices 122, 124 between their opened and closed positions. For instance, in one embodiment, the actuator assembly 126 may correspond to a magnetically activated actuator assembly. One example of a suitable magnetically activated actuator assembly is described in U.S. patent application Ser. No. 14/695,241 (Johnson et al.), filed on Apr. 24, 2015 and entitled “Magnetically Activated Arteriovenous Access Valve System and Related Methods,” the disclosure of which is hereby incorporated by reference herein in its entirety for all purposes. For instance, the actuator assembly 126 may include an implanted housing configured to house both a driver assembly (e.g., a gear pump or a plunger device) and a drive magnet that is rotatably coupled to the driver assembly. In such an embodiment, rotation of the drive magnet may rotatably drive the driver assembly so as to supply fluid to the first and second valve devices 122, 124 or to draw fluid out of the first and second valve devices 122, 124 depending on a rotational direction of the driver assembly. As described in the '241 application, such rotation of the drive magnet may be achieved, for example, using an external activator device including a rotatable activator magnet. Thus, by placing the external activator device adjacent to the exterior of the patient's skin, rotation of the activator magnet may rotate the drive magnet, thereby driving the driver assembly and causing the valve devices 122, 124 to be opened or closed.
In another embodiment, the actuator assembly 126 may correspond to an implanted device configured to receive the tip of a hypodermic needle to allow fluid to be supplied to and drawn out of the valve devices 122, 125. One example of such an actuator assembly is described in U.S. Pat. No. 8,764,698 (Cull) entitled “Arteriovenous Access Valve System and Process,” the disclosure of which is hereby incorporated by reference herein in its entirety for all purposes. For instance, the actuator assembly 126 may include an implanted housing defining a septum or injection port for receiving the tip a hypodermic needle. In such an embodiment, when fluid is injected or withdrawn through the septum or injection port via the needle, the valve devices 122, 124 may be opened or closed, respectively.
In alternative embodiments, it should be appreciated that the actuator assembly 126 may correspond to any other suitable device(s) or component(s) that is configured to actuate or adjust the valve devices 122, 124 between their opened and closed positions. For instance, any device(s) or component(s) that allows fluid to be supplied to and/or drawn out of the valve devices 122, 125 may correspond to an actuator assembly 126 suitable for use in the disclosed system 100.
Referring now to
As indicated above, the separate valve tubes 102, 104 of the disclosed system 100 may each include a valve device 122, 124 integrated therein and/or otherwise associated therewith. For instance, as shown in
It should be appreciated that, in several embodiments, the arterial/venous ends 108, 114 of the first and second valve tubes 102, 104 may be defined by their corresponding valve devices 122, 124 and/or their corresponding tube portions 132, 134. For instance, in one embodiment, the first tube portion 132 may be integrated into and/or extend through the first valve device 122 to the arterial end 108 of the first valve tube 102. Similarly, in one embodiment, the second tube portion 134 may be integrated into and/or extend through the second valve device 124 to the venous end 114 of the second valve tube 104.
As shown in the illustrated embodiment, the tube connector 106 may generally correspond to a hollow component extending lengthwise between a first end 136 and a second end 138, with the first end 136 being configured to be coupled to the first joint end 110 of the first valve tube 102 and the second end 138 being configured to be coupled to the second joint end 112 of the second valve tube 104. Specifically, as shown in
Such a configuration may create an overlapped joint or connection between the tube connector 106 and the valve tubes 102, 104. For example, as shown in
Additionally, as particularly shown in
It should be appreciated that the ends 136, 138 of the tube connector 106 may also be rounded-off or non-sharp to avoid stress-risers and to prevent wear from occurring at the interface between the tube portions 132, 134 and the connector 106.
Additionally, as shown in
It should be appreciated that the tube connector 106 may generally be formed from any suitable material. For instance, in several embodiments, the tube connector 106 may be formed from a rigid, biocompatible material, such as titanium or a rigid, biocompatible polymer material.
As indicated above, in several embodiments, each valve device 122, 124 may correspond to a balloon-actuated valve that is integrated into or otherwise disposed in-line within its corresponding valve tube 102, 104. For instance,
As shown, the valve device 122 may include a housing or outer sleeve 150 extending lengthwise between a first end 152 disposed at or adjacent to the arterial end 108 of the first valve tube 102 and a second end 154 opposite the first end 152. In several embodiments, the sleeve 150 may be configured to extend around a section of the first tube portion 132 of the first valve tube 102. In such an embodiment, as shown in
Additionally, as shown in
As shown in
It should be appreciated that the hoop strength of the outer sleeve 150 may generally correspond to any suitable value that allows the sleeve 150 to function as described herein. However, in a particular embodiment of the present subject matter, the outer sleeve 150 may have a hoop strength of greater than about 3,000 psi (e.g., 20.7 Mpa).
As indicated above, by providing an arteriovenous access valve system 100 including separate valve tubes 102, 104, the length of such valve tubes 102, 104 may be adjusted, as is desired or necessary, to suit the patient's body size, vascular system, access type and/or access location (e.g., the patient's arm versus the patient's thigh). For example,
Referring now to
As particularly shown in
Similar to the valve tubes 102, 104 described above, the separate valve tubes 202, 204 of the disclosed system 200 may each include a valve device 222, 224 (indicated by dashed lines in
It should be appreciated that, in addition to the valve tubes 202, 204, the graft 205 and the tube connectors 206, 207, the system 200 may also include any other additional system components, such as the actuator assembly 126 and the tubing 128, 130 of the system 100 described above with reference to
In several embodiments, the valve devices 222, 224 may correspond to balloon-actuated valves and, thus, may each include an inflatable balloon 258 (
It should be appreciated that the arteriovenous graft 205 may generally correspond to any suitable graft or other tube-like member. For example, the graft 205 may be formed from a flexible, biocompatible material, such as expanded PTFE or any other suitable biocompatible graft or tubing material. In another embodiment, the graft 205 may be formed from a woven or tissue-based material.
It should also be appreciated that the first and second tube connectors 206, 207 may generally be configured the same as or similar to the tube connector 106 described above. For example, the first tube connector 206 may generally correspond to a hollow component extending lengthwise between a first end 236 and a second end 238, with the first end 236 being configured to be coupled to the first joint end 210 of the first valve tube 202 and the second end 238 being configured to be coupled to the first graft end 211 of the graft 205. Specifically, as shown in
Similarly, the second tube connector 207 may generally correspond to a hollow component extending lengthwise between a first end 237 and a second end 239, with the first end 237 being configured to be coupled to the second graft end 213 of the graft 205 and the second end 239 being configured to be coupled to the second joint end 212 of the second valve tube 204. Specifically, as shown in
Such a configuration may create overlapped joints or connections between the tube connectors 206, 207 and the both the valve tubes 202, 204 and the graft 205. Similar to the embodiment described above with reference to
Additionally, similar to the tube connector 106 described above, each tube connector 206, 207 may also include features or design elements that assist in coupling the valve tubes 202, 204 and the graft 205 to the tube connector 206, 207 and/or assist in positioning the joint ends 210, 212 of the valve tubes 202, 204 and/or the ends 211, 213 of the graft 205 relative to the tube connector 206, 207. For instance, as shown in the illustrated embodiment, each tube connector 206, 207 may be flared outwardly at its first and second ends 236, 237, 238, 239 which may serve as a retention means for preventing the valve tubes 202, 204 and the graft 205 from being pulled off of the tube connector 206, 207. In addition, the ends 236, 237, 238, 239 of each tube connector 206, 206 may also be rounded-off or non-sharp. Moreover, as shown in the illustrated embodiment, each tube connector 206, 207 may also include an annular rib 246 extending outwardly from a central portion of the tube connector 206, 207 located between its first and second ends 236, 237, 238, 239 that may serve as a locating means for installing the valve tubes 202, 204 and the graft 205 onto the tube connectors 206, 207.
Further, in several embodiments, each tube connector 206, 207 may also include one or more inwardly extending channels or grooves 290 defined around its exterior. For example, as particularly shown in
It should be appreciated that, although the valve tubes 202, 204 shown in
It should also be appreciated that the present subject matter is also directed to a method for providing access between an artery and a vein of a patient. In one embodiment, the method may include assembling one or more of the components of the arteriovenous access valve system 100, 200 described herein (e.g., by coupling the joint ends 110, 112 of the valve tubes 102, 104 to the tube connector 106 or by coupling the valve tubes 202, 204 to the graft 205 via the first and second tube connectors 206, 207) and subsequently subcutaneously implanting such assembled components in the patient (e.g., by coupling the arterial end 108, 208 of the first valve tube 102, 202 to the patient's artery 14 and by coupling the venous end 114, 214 of the second valve tube 104, 204 to the patient's vein 16). In addition, the method may include opening first and second valve devices 122, 124, 222, 224 of the first and second valve tubes 102, 104, 202, 204 to allow blood to flow through the valve tubes 102, 104, 202, 204 between the artery 14 and the vein 16 of the patient and closing the first and second valve devices 122, 124, 222, 224 to prevent blood from flowing through the first and second valve tubes 102, 104, 202, 204 between the artery 14 and the vein 16 of the patient.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
