Authors report their experience between 1981 and 1989 in the surgical treatment of 24 patients, aged 11 to 68 years, with chronic aneurysm of the ascending aorta (14 cases) or acute aortic dissection (10 cases), 7 of them being in cardiogenic shock with cardiac tamponade. In 7 patients the classic Bentall technique was employed, in 7 a modified Bentall technique and in 10 cases reimplantation of the coronary arteries was performed. In 2 cases a coronary artery by-pass, by saphenous vein graft, was placed on the right coronary artery, which was involved in the dissection. Valved dacron conduits were always employed. Two patients died after the operation whereas no late deaths were recorded in a follow-up interval ranging from 3 months to 7 years. The modifications of the classic surgical technique described in 1968 by Bentall-De Bono are of primary importance in diminishing the operative mortality and the incidence of early and late complications in these patients, whose disease nonetheless remains a surgical challenge.