BackgroundsSurvival and aortic-related adverse events after thoracic endovascular aortic repair (TEVAR) for aortic intramural hematoma (IMH) and aortic dissection (AD) are controversial. We aimed to assess the preoperative characteristics and to evaluate TEVAR outcomes of acute type B IMH and AD.MethodsBetween June 2002 and May 2021, 83 patients with acute type B IMH and 755 patients with acute type B AD underwent TEVAR at the General Hospital of Northern Theater Command. We retrospectively analyzed data from these patients, including clinical characteristics and follow-up outcomes.ResultsThe patients with IMH were significantly older than the ones with AD (P < 0.001). Diabetes mellitus (P = 0.035) and ischemic cerebrovascular disease (P = 0.017) were more common in the IMH group than in the AD group. The results demonstrated a less long-term aortic-related death-free survival rate in the IMH group than the AD group for all the patients (P = 0.014) and the matched patients (P = 0.027). It also presents a lower long-term overall survival rate (P = 0.047) and aortic-related event-free rate (P = 0.048) in the IMH group than in the matched patients.ConclusionsCompared with AD patients, patients with IMH who underwent TEVAR had a worse long-term outcome of aortic-related survival in all and matched patients.