Shrapnel Injury Leading to Posterior Tibial Arteriovenous Fistula: A Complex Repair

Traumatic arteriovenous fistulas (AVFs) are a rare entity in vascular surgery and can lead to congestive heart failure, venous hypertension, severe leg swelling, and limb threatening ischemia. We present a case of a posterior tibial (PT) AVF associated with a popliteal artery aneurysm (PAA), requiring a bypass graft, ligation of the AVF, and a PT interposition graft. The patient was a 70-year-old Vietnam veteran with a history of lower extremity shrapnel injuries. He had presented with a nonhealing third toe ulcer, toe brachial index of 0, and a flat metatarsal pulse volume recording. Computed tomography angiography was performed, which revealed an occluded arteriomegalic superficial femoral artery with a reconstituted 2.0-cm PAA and a synchronous AVF between his PT artery and vein at a site with retained shrapnel. We performed PAA ligation with a common femoral artery to below-the-knee popliteal artery bypass with vein and AVF ligation. On-table angiogram, now without venous obscuration, showed occlusion of the PT AVF with reconstitution via the peroneal artery. A PT–PT interposition graft with a vein was performed, restoring in-line flow to his foot. At the 6-month follow-up examination, his toe amputation had healed, and the ankle brachial index was 1.1. Shrapnel injuries leading to traumatic AVFs are rarely reported in the surgical literature. Many will be treated endovascularly using covered stents to avoid open surgical exposure, which can be treacherous owing to the scarring and venous hypertension. Given the associated PAA with upstream superficial femoral artery occlusion, endovascular repair was not considered. Additionally, the preoperative imaging findings suggested a patent PT artery was present. It was only after ligation of the AVF that we discovered the occlusion of the distal PT with reconstitution via the peroneal artery; thus, a PT–PT interposition graft was created to reestablish the in-line flow (Figs 1 and 2). Traumatic AVFs are an infrequent disorder and will usually have a long latency period before discovery. Open and endovascular repairs have been documented. Given the uniqueness of each case, repair should be tailored to the patient.Fig 2Posterior tibial (PT) arteriovenous fistula (AVF). Forceps indicate clip used to ligate the AVF. Note marked dilation of the PT vein.View Large Image Figure ViewerDownload Hi-res image Download (PPT)