Direction Change in Distal Bypass Graft due to Increased Collateral Perfusion after the Free Flap Transfer

Abstract

Distal bypass combined with a free flap is a frequent surgical option for ischemic ulcers of the lower extremities. Here, we describe a patient in whom there was a change in the direction of blood flow in a distal bypass graft. A 68-year-old male patient with an ischemic ulcer on his left heel was referred to our facility by a local dermatology clinic. Surgical revascularization was performed between the popliteal artery and the dorsalis pedis artery using an ipsilateral great saphenous vein as the graft vessel. The wound site did not heal postoperatively, so it was covered using a free latissimus dorsi muscle flap. At the same time, the thoracodorsal artery was anastomosed to the bypass graft in an end-to-side manner to serve as a nutrient vessel. Initially, blood flow into the thoracodorsal artery from the bypass graft was via the popliteal artery. However, after occlusion of the proximal anastomotic site of the bypass graft, blood flow into the thoracodorsal artery from the bypass graft was via the dorsalis pedis artery, which was the distal anastomotic site. The change in direction of blood flow might have been the result of an increase in blood flow in the collateral vessels in the ischemic lower leg, which eventually overwhelmed the blood flow in the bypass graft.