ANEURYSMS OF THE DESCENDING THORACIC AORTA - 366 CONSECUTIVE CASES RESECTED WITHOUT PARAPLEGIA

Purpose: The aim of this study was to present a 20-year experience wit h a single method of passive distal perfusion during descending thorac ic aortic aneurysm resection. Method: Aortic repair with a Dacron graf t interposition was performed for 366 consecutive aneurysms located be tween the left subclavian artery and the crux of the diaphragm. The ex tent of aorta resected in 335 patients (91.5%) represented one third o r less of the aortic length. A 9 mm Gott shunt was cannulated proximal ly into the ascending aorta (235 cases), the aortic arch (60 cases), t he descending aorta (68 cases), or the left ventricle (3 cases) and in serted distally into the descending aorta (232 cases), the femoral art ery (127 cases), or the abdominal aorta (7 cases). Shunt flows were re corded in 91 cases and varied from 1100 mi to 4900 ml/min, (mean 2526 ml/min). Distal pressure during shunting was measured in 62 patients. It varied from 15 to 120 mm Hg (mean 64.5 mm Hg). The aortic cross-cla mp time varied from 8 to 124 minutes (mean 30 minutes). Results: The h ospital death rate was 12% overall and 9.9% (35/351) if ruptured aneur ysms are excluded. Among 359 operating room survivors, neither immedia te nor delayed ischemic spinal cord deficit occurred. Transient renal dysfunction occurred in nine patients (2.4%) and kidney failure in one (0.2%). Five deaths (1.3%) were shunt related. Conclusion: Distal per fusion with the 9 mm Gott shunt has proven to be an effective method t o preserve spinal cord function. The limited extent of aorta resected and the brief aortic cross-clamp time may also be interactive factors of protection.