Creation of a transrenal arteriovenous dialysis shunt: Feasibility study in a swine model

PURPOSE: To investigate the feasibility of percutaneous renal artery and ve in access for the creation of a transrenal arteriovenous hemodialysis graft . MATERIALS AND METHODS: Renal-artery-to-ipsilateral-renal-vein conduits were constructed with use of entirely percutaneous techniques in seven swine. R enal artery and vein access was performed in six animals with use of a retr ograde (inside-out) technique and in one animal with use of an antegrade (o utside-in) technique. Modified 8-F sheaths were used in the first three ani mals and Wallgrafts were used in the final four animals to form the arteria l and venous limbs of each shunt. The arterial and venous limbs were joined together by a subcutaneous segment of 6-mm reinforced polytetrafluoroethyl ene (PTFE) in five animals and by external conduits in two animals. Wallgra fts; were deployed from the renal artery and vein into the segments of PTFE . The free ends of each conduit were tunneled and joined together to close the arteriovenous circuit. Post-shunt angiography was used in all animals t o document successful shunt creation and demonstrate rapid arteriovenous sh unting as a determinant of technical feasibility. Two of the seven animals received additional anticoagulation therapy and/or antiplatelet therapy to prevent shunt thrombosis during the follow-up period. The three initial ani mals were killed within 2 hours of shunt creation, and two of the remaining four animals returned for angiographic follow-up, one on day 2 and one on day 9. All animals underwent a complete necropsy to assess for potential co mplications including hemorrhage and vascular or bowel injury. RESULTS: Retrograde renal arterial and venous access was successful in all six animals in which it was attempted. Five of six arterial accesses and fo ur of six venous accesses traversed the peritoneum with two arterial access es and one venous access penetrating a loop of large bowel. Antegrade acces s was performed and successfully accomplished in the final animal. Brisk ar teriovenous shunting was demonstrated on completion angiography in all anim als. Graft occlusion was present in the two animals that returned for follo w-up and two animals died before follow-up as a result of graft leakage and subsequent hemorrhage. Minimal perinephric and intrarenal hemorrhage was d emonstrated at necropsy after shunt insertion in the remaining five animals . Renal infarction was present in all kidneys used for transrenal access. CONCLUSION: The transrenal approach for the creation of a percutaneous arte riovenous shunt is, feasible after renal artery and vein access by either t he retrograde or antegrade technique. Additional technical refinements of t he procedure and the devices used will be necessary before follow-tip studi es are conducted.