Fourteen patients with aortic regurgitation due to aortitis syndrome that underwent surgical therapy were studied with particular emphasis on the long term merits of Bentall's operations over the conventional valve replacement. They were divided into two groups; Group A: 6 aortic valve replacements (AVRs) and Group B: 8 Bentall's operations. Post operative complications related to aortitis syndrome developed in 3 cases; a case of paravalvular leakage (Group A) and two cases of aneurysm formation at the coronary artery anastomotic sites (Group B). We speculated that these complications were due to abnormal healing and recurrent inflammatory process of the disease. Therefore we think that conventional valve replacement is not suited to cope with these problems. Since 1984, we have adopted the policy to perform Bentall's operations for all patients with aortitis requiring valve replacement. Bentall's operation required longer aortic cross-clamp time (212.1 +/- 53.9 min) than AVRs (73.0 +/- 25.0) and was more aggressive. However no patients with our current technique to reimplant the coronary artery button and distal graft to aorta anastomosis, which has been used since 1984, has developed pseudoaneurysm or valvular leakage. We conclude that our modified Bentall's operation is effective even for patients who have active aortitis syndrome or need redo operations.