Outcome after Endovascular Repair of Subacute Type B Aortic Dissection: A Combined Series from Two Greek Centers

Background: The aim of this study is to document the outcome following endovascular treatment of subacute type B aortic dissection (AD). Methods: Between October 2000 and June 2014, 40 patients (33 men, mean age 65 [range 35-87] years) with type B AD underwent thoracic endovascular aortic repair (TEVAR) during the subacute phase (defined as 15-90 days from the onset of symptoms). Indications for intervention were acute aortic enlargement, resistant hypertension, and/or intractable pain. The primary outcome was survival. Secondary outcome measures included reinterventions and aortic remodeling (i.e., the fate of the false lumen [FL] post-TEVAR, which was classified as complete, partial, or no thrombosis of the FL). Results: The intraprocedural technical success was 95% (2 proximal endoleaks). Three patients died within 30 days (7.5%), all 3 from dissection-related causes (retrograde type A AD in 2, ruptured thoracic aorta in 1). Another 11 deaths occurred during follow-up (median 64 months, range 1-167), 3 of which were dissection-related. The 1-, 3-, and 5-year Kaplan-Meier survival probability was 87.5%, 79%, and 71.5%, respectively. With regard to the aortic remodeling, there was complete FL thrombosis in 10 (25%) patients, partial thrombosis in 22 (55%), and patent FL with no thrombosis in 8 (20%) patients. There was no statistically significant association between FL status and survival, or between FL status and initial extent of dissection. However, there was a statistically significant association between FL status and reinterventions, the latter being more frequent in patients with no FL thrombosis. Conclusions: TEVAR for subacute type B AD appears to be associated with acceptable perioperative and long-term results. In contrast to previous reports, there is still a risk for postoperative retrograde type A AD even when patients are treated in the subacute phase when the aorta is less fragile. Aortic remodeling occurs in the majority of patients, but requires frequent aortic reinterventions, an observation that underlines the need for life-long surveillance.