Aortic Diameter ≥5.5 cm Is Not a Good Predictor of Type A Aortic Dissection

BACKGROUND: Studies of aortic aneurysm patients have shown that the risk of rupture increases with aortic size. However, few studies of acute aortic dissection patients and aortic size exist. We used data from our registry of acute aortic dissection patients to better understand the relationship between aortic diameter and type A dissection. METHODS AND RESULTS: We examined 591 type A dissection patients enrolled in the International Registry of Acute Aortic Dissection between 1996 and 2005 (mean age, 60.8 years). Maximum aortic diameters averaged 5.3 cm; 349 (59%) patients had aortic diameters