Thirty of 33 patients (ages 18-67) with acute dissection of the ascending aorta underwent surgical intervention. There were four deaths. There were eight male and five female patients and 15 patients were known to be hypertensive. Severe chest pain, widened mediastinum (demonstrated radiographically), and varying degrees of aortic insufficiency were present in each patient. Heart failure was present in 13 patients, numbness and coolness of an extremity in seven patients, and central nervous system changes were present in three patients. The diagnosis in each instance was confirmed by aortography. Three patients treated nonoperatively died during hospitalization following aortic rupture into the mediastinum and pericardium. The remaining 30 patients were managed by insertion of a woven Dacron((R)) graft sutured distal to the coronary arteries and proximal to the origin of the great vessels. This was accompanied with resuspension of the aortic valve in 24 patients and valve replacement in six patients. Each of the latter six patients had a history of aortic valve disease. The goals of the operation were: 1) correction of the accompanying aortic insufficiency, either by valve replacement or resuspension of the valve and 2) placement of a prosthetic graft into the ascending aorta, thereby obliterating the false lumen and preventing involvement of the coronary arteries or rupture into the mediastinum or the pericardium. Hypertensive patients were managed pre- and postoperatively with nitroprusside and then with propranolol HCI, methyldopa, or hydralazine HCI and hydrochlorothiazide. One late death occurred six months after myocardial infarction and a second late death occurred from a presumed cardiac arrhythmia. One patient had a femorofemoral graft two months after the initial operation and another patient has mild aortic insufficiency. It is concluded that prompt surgical management is mandatory in acute ascending aortic dissection, and in most patients aortic valve competency can be re-established with resuspension of the valve preventing the added morbidity associated with a prosthetic valve. Four patients have been followed for five years and additional follow-up data will better define long-term survival.