Retrospective data regarding 290 patients suffering from spontaneous aortic dissection between January 1976 and June 1987 are reported. Dissection was always documented by retrograde aortography and data were collected from 11 catheterization laboratories operating in North-East Italy. The results show that over a 12-year period there was an increase in cases, an increase in the number of operations and a decline in operative mortality. Multivariate discriminant analysis demonstrated that acute myocardial infarction, persistent shock and persistent central neurologic deficit were significant independent predictors of operative mortality in type A patients. Only persistent shock was significantly related to higher operative mortality in type B patients. Late deaths occurred in 14/118 operated patients, and were mostly secondary (directly or indirectly) to aortic dissection. Discharged patients underwent frequent medical checks and chronically received drugs to control hypertension and reduce inotropism. Most of them (73.7%) were asymptomatic: careful post-operative medical assistance is necessary to guarantee the long-term success of surgical treatment.