Background: Recent studies have shown an favorable short-term prognosis of patients with type A acute aortic intramural hematoma (IMH). The difference of aortic pathology may have a different impact on clinical course compared with classic aortic dissection (AD). The purpose of this study was to elucidate clinical features and long-term prognosis of patients with type A IMH.
Methods and results: Clinical data were compared retrospectively between 30 patients with acute type A IMH (IMH group) and 101 patients with acute type A AD (AD group) who were admitted to our institutions from 1988 to 1998. In AD group, 72 patients underwent surgical repair and 29 patients were treated medically. All patients in IMH group were treated initially with supportive medical therapy. Thirteen patients who demonstrated progression to AD or increase in size of hematoma underwent timed surgical repair except for 1 patient. The overall in-hospital mortality rate in IMH group was significantly lower than that in AD group (7% and 34%, P=0.004). Follow-up periods were 56+/-37 (IMH group) and 60+/-42 months (AD group), which revealed 1 and 6 late deaths, respectively. The actuarial survival rates in IMH group were all 90% at 1, 2, and 5 years, which were significantly higher than those in AD group (67%, 66%, and 62%, respectively; P=0.004).
Conclusions: Patients with type A IMH have better long-term prognosis than patients with AD.