Long-term follow-up of acute type B aortic dissection: Ulcer-like projections in thrombosed false lumen play a role in late aortic events

ObjectivePatients with Stanford type B dissection treated medically during the acute phase have a risk of surgery and aortic rupture during the chronic phase. We investigated the predictors for late aortic events by focusing on the false lumen status with computed tomography.MethodsA total of 160 patients were enrolled in the study, with a mean follow-up interval of 44.6 ± 25.4 months. Patients were divided into 3 groups according to the false lumen status at the time of onset: group T, thrombosed in 49 patients (30.6%); group U, thrombosed with ulcer-like projections in 52 patients (32.5%); and group P, patent in 59 patients (36.9%).ResultsThe mean aortic enlargement rate of groups U and P was greater than that of group T (0.40 ± 0.91 mm/month in group U, 0.44 ± 0.49 mm/month in group P, and −0.016 ± 0.23 mm/month in group T). The event-free rate in groups U and P was lower than in group T: 5-year event-free rates of 67.4% ± 8.2% in group U and 57.7% ± 10.9% in group P versus 95.0% ± 4.9% in group T (group T vs group U: P = .0011, group U vs group P: P = .96, group P vs group T: P = .0004). Cox regression analysis revealed that the false lumen status (patent or ulcer-like projections) (P = .029), maximum aortic diameter at onset (P < .0001), and patient age (P = .0069) were predictors of the late aortic events.ConclusionsIn type B aortic dissection, a thrombosed false lumen with ulcer-like projections and a patent false lumen had an influence on late aortic dilation and late aortic events.