Hypothermic circulatory arrest: Safety and efficacy in the operative treatment of descending and thoracoabdominal aortic aneurysms

Background. The safety and efficacy of hypothermic circulatory arrest in the operative treatment of descending thoracic aortic aneurysms and thoracoabdominal aortic aneurysms are not clearly established. We evaluated our experience with repair of descending thoracic and thoracoabdominal aortic aneurysms using hypothermic circulatory arrest. Methods. In all, 111 patients with descending thoracic aortic aneurysms (83) or thoracoabdominal aortic aneurysms (28) underwent graft replacement of the involved aortic segments using hypothermic circulatory arrest. The technique was used when the location, extent, and severity of disease precluded placement of a proximal aortic clamp. Mean patient age was 61.4 +/- 13.1 years and 81 (73%) were male. Nine patients (8%) presented with acute dissection; 74 (67%) had chronic dissection; 56 patients (51%) required emergency operations, including 16 (14%) with ruptured aneurysms. Mean circulatory arrest time was 39.7 +/- 16.2 minutes. Results. There were no intraoperative deaths. There were 31 operative deaths (28%), including 23 patients (21%) who died within 30 days. Operative mortality was 29% (30 of 102) for patients undergoing emergent or urgent operations and 1% (1 of 9) for all elective cases (p = 0.4). Postoperative paraplegia developed in 1 patient (1%) and 17 patients (15%) had postoperative renal failure. Cardiac complications occurred in 26 patients (23%), reoperation for bleeding in 6 (5%), tracheostomy was required in 24 (22%), and 10 (9%) sustained postoperative stroke. Conclusions. When cross clamping the aorta is not feasible, hypothermic circulatory arrest can be performed but with an increased morbidity and mortality rate.