Association of Painless Acute Aortic Dissection With Increased Mortality

To evaluate the clinical characteristics and outcomes of patients with painless acute aortic dissection (AAD). For this study conducted from 1997 to 2001, we searched the International Registry of Acute Aortic Dissection to identify patients with painless AAD (group 1). Their clinical features and in-hospital events were compared with patients who had painful AAD (group 2). Of the 977 patients in the database, 63 (6.4%) had painless AAD, and 914 (93.6%) had painful AAD. Patients in group 1 were older than those in group 2 (mean ± SD age, 66.6±13.3 vs 61.9±14.1 years; P=.01). Type A dissection (involving the ascending aorta or the arch) was more frequent in group 1 (74.6% vs 60.9%; P=.03). Syncope (33.9% vs 11.7%; P