Different clinical features of aortic intramural hematoma versus dissection involving the ascending aorta

Objectives The goal of this study was to test the hypothesis that the absen ce of direct flow communication through intimal tear in aortic intramural h ematoma (AIH) involving the ascending aorta has different clinical impact o n clinical course compared with typical aortic dissection (AD). Background Although emergent surgical repair has been applied for patients with proximal AIH as if it was typical AD, the natural history of proximal AIH is not known clearly yet. Methods Direct comparison of the clinical data of 81 patients with proximal AD and 24 patients with AIH was performed retrospectively. Results Patients with AIH were older (67 +/- 10 vs. 50 +/- 13, p = 0.001), and female gender was more predominant in AIH (19/24 vs. 29/81, p = 0.001). The development of mediastinal hemorrhage and pericardial and pleural effu sion was more frequent in patients with AIH than it was in patients with AD . Although medical treatment tvas more frequently selected in the AIH group (75% vs. 15%, p = 0.001) due to old age and other associated medical disea ses, the mortality rate with medical treatment was much lower in patients w ith AIH than it was in patients with AD (6% vs. 58%, p = 0.003). In follow- up imaging studies of 13 patients who survived AIH without surgical repair, seven patients showed complete resolution. Typical AD developed in three p atients, and the other three patients showed focal AD only in the descendin g aorta. The two-year survival rate did not show significant difference (84 % +/- 6% in AIH vs. 76% +/- 17% in AD, p = 0.47). Conclusions Absence of continuous flow communication can explain a more fav orable clinical course of AIH than for AB, and medical treatment with frequ ent imaging follow-up and timed elective surgery in cases with complication s can be a rational option for patients with proximal AIH. (J Am Coll Cardi ol 2001;37:1604-10) (C) 2001 by the American College of Cardiology.