Systems and methods for creating arteriovenous (av) fistulas

Abstract

A system for creating an arteriovenous (AV) fistula comprises a vessel access sheath having a hollow interior and an exit port, a side access needle catheter configured to fit within the hollow interior of the sheath, a needle configured to be inserted into a blood vessel through the side access needle catheter, a toggle delivery catheter configured to fit within the hollow interior of the sheath, and a toggle apparatus configured to be delivered into a vessel through the toggle delivery catheter. The toggle apparatus comprises a shaft and a toggle member pivotably attached to a distal end of the shaft. A source of RF energy or resistive heat energy may be provided for application to the toggle member and/or to a heater insert in the toggle delivery catheter, for the purpose of creating the fistula.

What is claimed is: 
     
         1 . A method, comprising:
 inserting a guidewire through a first body lumen and into a second body lumen adjacent to the first body lumen;   advancing over the guidewire a medical device into the first body lumen, the medical device having a first portion and a second portion slidably coupled to the first portion, the second portion including a shaft and a non-expandable member, the medical device movable between a first configuration and a second configuration;   moving the medical device from its first configuration to its second configuration such that the second portion of the medical device moves into a second body lumen; and   activating an energy source associated with at least one of the first portion or the second portion of the medical device such that a concentric opening is created between the first body lumen and the second body lumen.   
     
     
         2 . The method of  claim 1 , wherein the concentric opening is formed using radiofrequency (RF) energy. 
     
     
         3 . The method of  claim 1 , wherein the second portion of the medical device moves in a first direction when moving from its first configuration to its second configuration, the method further comprising moving the second portion of the medical device in a second direction opposite the first direction before the activating. 
     
     
         4 . The method of  claim 1 , further comprising activating the energy source associated with the at least one of the first portion or the second portion of the medical device such that the first body lumen is coupled to the second body lumen. 
     
     
         5 . The method of  claim 4 , wherein the first body lumen is coupled to the second body lumen with at least one of a thermal resistance, a radiofrequency (RF) energy or an ultrasonic energy. 
     
     
         6 . The method of  claim 1 , further comprising:
 moving the non-expandable member of the second portion of the medical device towards the first portion of the medical device before the activating; and   maintaining the second portion in a position proximate the first portion with a force in the range of about 100 grams of force to about 1000 grams of force.   
     
     
         7 . The method of  claim 1 , further comprising:
 moving the non-expandable member of the second portion of the medical device towards the first portion of the medical device before the activating; and   applying a pressure between the first portion and the second portion in the range of about 100 to about 1000 g.   
     
     
         8 . The method of  claim 1 , further comprising:
 measuring a distance between the first portion and the second portion; and   outputting an indication associated with the measurement of the distance.   
     
     
         9 . The method of  claim 1 , further comprising:
 sensing a distance between the first portion and the second portion; and   outputting an indication associated with the measurement of the distance.   
     
     
         10 . A method of creating an arteriovenous (AV) fistula between a first vessel and an adjacent second vessel, comprising:
 inserting a guidewire into the first vessel and the second vessel using a needle;   positioning an access sheath within the first vessel and the second vessel over said guidewire;   advancing over the guidewire and through the access sheath a fistula creation device having a main body having a first tissue contacting surface, a shaft slidably coupled to the main body, and a non-expandable member coupled to the shaft and movable relative to the main body, the non-expandable member having a second tissue contacting surface;   positioning the main body in the first vessel;   moving the shaft such that the non-expandable member is positioned in the second vessel;   moving the non-expandable member relative to the main body to contact a side wall of the second vessel; and   creating an aperture through the first vessel and the second vessel between the first tissue contacting surface and the second tissue contacting surface.