BACKGROUND: We aimed to describe characteristics and outcomes in a nationwide population of patients with acute type A and type B aortic dissection.

METHODS: All patients in Denmark with a first-time diagnosis of acute aortic dissection between 2006 and 2015 were identified by national registries. The main outcomes were in-hospital mortality and long-term survival in hospital survivors.

RESULTS: The study population comprised 1157 (68%) patients with type A aortic dissection and 556 (32%) patients with type B aortic dissection, median age of 66 (57-74) years and 70 (61-79) years, respectively. Men accounted for 64%. Median follow-up was 8.9 (6.8-11.5) years. Of patients with type A aortic dissection, 74% were managed surgically, whereas 22% of the patients with type B aortic dissection were managed with surgery or endovascular technique. In-hospital mortality was 27% for type A aortic dissection overall (surgery, 18%; no surgery, 52%) and 16% for type B aortic dissection (surgery or endovascular treatment, 13%; conservative treatment, 17%; P < .001, type A vs type B). Of patients discharged alive, survival was persistently better for type A aortic dissection than for type B aortic dissection (P < .001). Unadjusted 1- and 3-year survival of patients with type A aortic dissection discharged alive was 96% and 91%, respectively, for surgically managed and 88% and 78% without surgery. For type B aortic dissection, the numbers were 89% and 83% for endovascular/surgically managed and 89% and 77% for conservatively managed.

CONCLUSIONS: We found higher in-hospital mortality for type A and type B aortic dissection than is reported from referral center registries. Type A aortic dissection had the highest mortality rate during the acute phase, whereas for patients who were discharged alive, the mortality rate was higher for patients with type B aortic dissection.