Subclavian Graft Thrombosis As an Alternative Cause for Delayed Spinal Cord Ischemia Following Hybrid Aortic Arch Repair

Abstract

PINAL CORD ISCHEMIA is a potentially devastating complication following any repair of the descending thoracic aorta. The literature suggests that the risk with descending aortic surgery may be lower with endovascular compared with open intervention. 1,2 Current estimates for the incidence of spinal cord ischemia with endovascular repair is in the range of 3% to 7%. 1-3 Thoracic aortic aneurysmal disease involving the aortic arch conventionally has required open repair involving cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest. Despite technical advances in surgical technique and perioperative care, the risk of mortality or significant morbidity remains high. 4,5 Hybrid arch repair is an evolving surgical approach for diffuse aortomegaly. It involves 2 steps, which can be performed together during a single surgery or staged over time. The first step involves conventional open aortic branch revascularization, while thoracic endovascular aortic repair (TEVAR) completes the process. Various approaches to the hybrid arch repair exist, with a wide range of reported incidence of neurologic complications. 6-8 Several risk factors have been identified for spinal cord ischemia in patients undergoing TEVAR, including previous abdominal aortic repair, hypotension, coverage of the left subclavian artery, and extensive endograft coverage. 9-16 The authors present a case of left subclavian graft thrombosis as a possible new etiology for delayed paraplegia in a patient following hybrid arch repair.