Percutaneous extra-anatomical bypass stenting for AVF elbow perforating vein stenosis with venous hypertension.

Arteriovenous fistulas (AVF) are the preferred access for hemodialysis, but venous outflow stenosis or occlusion can lead to fistula failure, venous hypertension and compromised dialysis adequacy. We reported a case of a 44-year-old male with a left radiocephalic fistula and severe stenosis of the perforating vein leading to aneurysm formation and inability to cannulate the AVF. After initial PTA failed to fully resolve the outflow obstruction and venous hypertension, an extra-anatomical bypass technique was performed. In this minimally invasive approach, a subcutaneous tunnel was created between two incisions to allow guidewire- and sheath-assisted establishment of a direct conduit from the forearm cephalic vein to the upper arm basilic vein, thereby bypassing the stenotic perforating vein. Two covered stents (Covera, BD) were deployed across the stenotic segment via this extra-anatomical route, followed by post-dilation. The procedure was guided by ultrasound and angiography. The extra-anatomical bypass using covered stents via a subcutaneous tunnel effectively resolved the venous outflow obstruction and alleviated venous hypertension in this patient, with immediate restoration of flow and thrill.