Evolution of surgical techniques for aneurysms of the descending thoracic aorta: twenty-nine years experience with 659 patients.

Between 1953 and 1993, 659 patients underwent descending thoracic aneurysm resection. The most common etiology was atherosclerosis. Pain was the main presenting symptom. Perioperative mortality fell from 24.2% between 1953 and 1964 to 14.3% between 1970 and 1993. Paraplegia occurred in 4.1% (27/659) patients overall and was little affected by time of operation or use of atriofemoral bypass. Paraparesis occurred in 5.9% (39/659) patients and was reduced by use of atriofemoral bypass. The low rate of paraparesis in the earlier experience was offset by the higher perioperative mortality from hemorrhage, attributable to the use of systemic heparin. The use of heparin-free circuits with centrifugal pumps should be considered in patients likely to have a clamp time greater than 30 minutes. The major source of perioperative morbidity and mortality was cardiac causes (48%) followed by perioperative hemorrhage (14.4%), pulmonary complications (14.4%), and rupture of another aneurysmal segment (12.0%). Late mortality occurred most commonly from cardiac causes (30.6% of deaths) and rupture of another aneurysm (16.3% of deaths). Improvement in results was due to general refinements of management in all areas rather than any single factor. These results indicate that complete preoperative assessment of the patient and the entire aorta is essential and that regular life-long follow-up is critical in order to avoid unnecessary morbidity and mortality from cardiac, cerebrovascular, or subsequent aneurysmal complications.