Predictors of late aortic events after Stanford type B acute aortic dissection

Objective: Patients with Stanford type B acute aortic dissection usually receive medical treatment during the acute phase. The present study aimed to elucidate the factors predicting late aortic events in patients treated conservatively for acute type B dissections. Methods: From March 1991 to March 2011, 117 patients were enrolled in the present study, with a mean follow-up period of 5.1 +/- 4.1 years. The patients were divided into 4 groups according to their false lumen status at onset: group F, fully open (n=26, 22.2%); group P, partially thrombosed (n=23, 19.6%); group U, ulcer-like projections (n=22, 18.9%); and group T, completely thrombosed (n=46, 39.3%). Results: Long-term survival did not significantly differ among the groups. The Kaplan-Meier event-free rate curve showed that aortic events occurred less frequently in group T than in the other 3 groups; the 5-year event-free rate was 65.4%, 58.8%, 36.1%, and 95.7% for groups F, P, U, and T, respectively. Cox regression analysis showed that the presence of ulcer-like projections (P=.016) and a maximum aortic diameter of >= 40 mm (P=.003) were predictors of late aortic events. Conclusions: When patients have a maximum aortic diameter of >= 40 mm or ulcer-like projections at onset, early surgical intervention should be considered to prevent positive remodeling of the aorta.