Method: Two hundred twenty-one cases have been operated for type A aortic dissection in Nagoya University group for last 5 years. Ascending aortic replacement underwent in 136 cases (group Asc) and aortic arch replacement was done in 80 cases (group Arc). Comparative study is performed to estimate the clinical efficacy or aortic arch replacement for type A aortic dissection.Result: The entry of aortic dissection was located in the ascending aorta in 76% of group Asc and in aortic arch in 64% of group Arc. Average age of group Asc was significantly older than group Arc (62 ± 13 vs. 55 ± 14 year, p = 0.006). However, there were no significant differences between groups in emergency operation rate (80% vs. 79%) and in any preoperative symptoms (hemodynamic compromise, cardiac arrest, neurologic dysfunction, cardiac tamponade, aortic valve regurgitation, myocardial infarction, renal or hepatic dysfunction and leg ischemia). As brain protection, isolated cerebral perfustion and retrograde cerebral perfusion were performed in 40% and 43% of group Asc and in 60% and 24% in group Arc. Bypass time of group Arc were significant longer than group Asc (256 ± 111 vs. 323 ± 112 min., p < 0.0001). However, cardiac ischemic time and lowest body temperature revealed no significant differences. Moment of awakening was similar but intubation period in group Acr was longer than group Asc. There were no significant differences in neurologic outcome (21%, 18%), cardiac (9%, 14%), pulmonary (49%, 56%), renal (12%, 18%), hepatic complication (6%, 8%). Early mortality (18%, 14%) and three years survival rate (68%, 72%) were same. The rate of redo of rupture of group Arc was smaller than group Asc (10%, 2%, p = 0.0316).Conclusion: Aortic arch replacement for type A aortic dissection revealed the same morbidity and mortality and better long term event free rate than solely ascending aortic replacement even in emergency operations.