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 <5.5 cm and 229 (40%) patients had aortic diameters <5.0 cm. Independent predictors of dissection at smaller diameters (<5.5 cm) included a history of hypertension (odds ratio, 2.17; 95% confidence interval, 1.03 to 4.57; P =0.04), radiating pain (odds ratio, 2.08; 95% confidence interval, 1.08 to 4.0; P =0.03), and increasing age (odds ratio, 1.03; 95% confidence interval, 1.00 to 1.05; P =0.03). Marfan syndrome patients were more likely to dissect at larger diameters (odds ratio, 14.3; 95% confidence interval, 2.7 to 100; P =0.002). Mortality (27% of patients) was not related to aortic size. Conclusions— The majority of patients with acute type A acute aortic dissection present with aortic diameters <5.5 cm and thus do not fall within current guidelines for elective aneurysm surgery. Methods other than size measurement of the ascending aorta are needed to identify patients at risk for dissection.

Background— Follow-up survival studies in patients with acute type B aortic dissection have been restricted to a small number of patients in single centers. We used data from a contemporary registry of acute type B aortic dissection to better understand factors associated with adverse long-term survival. Methods and Results— We examined 242 consecutive patients discharged alive with acute type B aortic dissection enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1996 and 2003. Kaplan-Meier survival curves were constructed, and Cox proportional hazards analysis was performed to identify independent predictors of follow-up mortality. Three-year survival for patients treated medically, surgically, or with endovascular therapy was 77.6±6.6%, 82.8±18.9%, and 76.2±25.2%, respectively (median follow-up 2.3 years, log-rank P =0.61). Independent predictors of follow-up mortality included female gender (hazard ratio [HR],1.99; 95% confidence interval [CI], 1.07 to 3.71; P =0.03), a history of prior aortic aneurysm (HR, 2.17; 95% CI, 1.03 to 4.59; P =0.04), a history of atherosclerosis (HR, 2.48; 95% CI, 1.32 to 4.66; P <0.01), in-hospital renal failure (HR, 2.55; 95% CI, 1.15 to 5.63; P =0.02), pleural effusion on chest radiograph (HR, 2.56; 95% CI, 1.18 to 5.58; P =0.02), and in-hospital hypotension/shock (HR, 12.5; 95% CI, 3.24 to 48.21; P <0.01). Conclusions— Contemporary follow-up mortality in patients who survive to hospital discharge with acute type B aortic dissection is high, approaching 1 in every 4 patients at 3 years. Current treatment and follow-up surveillance require further study to better understand and optimize care for patients with this complex disease.

This narrative review summarizes published evidence on diagnosis and management of acute aortic syndromes with a focus on the evolving roles of medical therapy