Degenerative and atherosclerotic aneurysms of the thoracic aorta. Determinants of early and late surgical outcome.

To identify significant predictors of early and late mortality, multivariate discriminant analyses were applied to the clinical outcome of 175 consecutive patients with thoracic aortic aneurysms operated upon over a 20 year span. Only atherosclerotic and degenerative aneurysms were included; the patients were segregated into two groups according to location of the aneurysm. The ascending aortic aneurysm group consisted of 124 patients, 85% of whom required concomitant aortic valve replacement. There were 51 patients in the descending aortic aneurysm group. Mean follow-up was 4.9 years (maximum of 19 years), with a total of 860 patient-years of follow-up. Multivariate analyses revealed that surgical priority and advanced age were independent determinants of hospital mortality in the ascending group; for the descending group, surgical priority and the presence of congestive heart failure were the strongest predictors of hospital mortality. Late mortality in the ascending group correlated with advanced age. Hypertension and the presence of preoperative congestive heart failure were independent determinants of late mortality in the descending group. Several variables did not have any independent bearing on hospital or late mortality, including etiology and location of the aneurysm, previous myocardial infarction, chronic lung disease, and concomitant aortic valve replacement. High-risk subgroups of patients with thoracic aortic aneurysms can be identified by these variables. Aggressive medical plus surgical management and operation prior to aneurysm rupture is necessary to improve both early and long-term survival rates.