RISK OF REPLACEMENT OF DESCENDING AORTA WITH A STANDARDIZED LEFT-HEART BYPASS TECHNIQUE

Replacement of the descending aorta for aneurysms (51%) and dissection (49%) was performed in 132 patients with a highly standardized left h eart vortex-pump bypass. No adjuncts other than staged aortic clamping and intercostal artery reconnection were used to reduce spinal cord i njury in extensive involvement. Four patients (3%) died early, two of cardiac cause, and nine (7%) died late. Complications of vital organ f unction occurred in eight patients, two having reversible renal failur e and six spinal cord injury that was permanent in three (2.3%). Cord injury occurred only in replacement beyond thoracic segment 8 and coul d not be completely avoided despite distal intercostal artery reconnec tion in two cases; in the other four cases such vessels either did not appear worth reconnecting or were sacrificed in emergency operations. We conclude that left heart bypass effectively unloads the proximal c irculation during aortic occlusion while maintaining adequate perfusio n of distal vital organs as evidenced by low rates of early mortality and renal failure. The remaining risk of spinal cord damage may be low ered by more aggressive reconnection of all distal intercostal arterie s and by extending the permissible cord ischemic period by means of hy pothermia.