Whether patients with bicuspid aortic valves are susceptible not only to ascending aortic dilatation but also to dilatation of the remaining aorta is uncertain. This study evaluated the possible correlation between ascending aortic dilatation and dilatation of the remaining aorta in patients with bicuspid and tricuspid aortic valves, respectively.The entire aortas of 97 patients (bicuspid in 62, tricuspid in 35) undergoing replacement of the ascending aorta because of ascending aortic pathology (78 with and 19 without concurrent valve pathology) were preoperatively evaluated using computed tomography scanning.Aortic dimensions distal to the ascending aorta were smaller in patients with bicuspid aortic valves than in patients with tricuspid aortic valves (P .2).Patients with bicuspid aortic valves and dilatation of the ascending aorta consistently had smaller dimensions of the remaining aorta compared with patients with tricuspid aortic valves. Concomitant dilatation of the descending aorta was predominantly found in patients with tricuspid aortic valves.