Aortic Dissection in Patients With Bicuspid Aortic Valve-Associated Aneurysms

Patients with bicuspid aortic valves have a significantly increased incidence of aortic complications including type A aortic dissection.  The authors studied 1181 patients with bicuspid aortic valves and sinus of valsalva or ascending aortic aneurysms with diameter greater than or equal to 4.7 cm on CT scan or MRI.  The prevalence of type A dissection identified by initial imaging or detected at operation or during surveillance follow up was 5.3%.  The probability of surgical intervention for aortic expansion or dissection among patients undergoing surveillance was 16% at 1 year and 50% at 6 years follow up.  The authors found the cross-sectional area of the ascending aorta or sinuses of Valsalva to height ratio to be the best predictor of type A dissection, and recommend aortic replacement in patients with bicuspid aortic valves and aortic diameter greater than 5 cm or cross sectional area to height ratio greater than 10 cm²/m.