Risk of aortic dissection after aortic valve replacement.

Little information is available regarding the incidence of aortic dissection after previous aortic valve replacement (AVR), and factors associated with its development. Therefore, a meta-analysis of the literature was performed, and a patient population was studied retrospectively. Data from published studies showed that 87% of 31 patients were men (mean age 60 years), and 68% were known to have systemic hypertension. A dilated ascending aorta was observed at the time of AVR in 88% of patients. AVR was performed because of pure aortic regurgitation in 55% of patients, and combined aortic stenosis and regurgitation in 23%. More than 50% of patients did not survive dissection. The present series consisted of 7 patients. Four patients were known to the department before dissection occurred, and the other 3 were referred by other hospitals. Eighteen of 330 patients with previous AVR whose data were stored in an echocardiographic data base had an ascending aortic diameter > 50 mm. Of these 18 patients, aortic dissection occurred in 4. Three of the remaining 14 patients underwent elective ascending aortic replacement. Characteristics including sex, age, severity of dilatation, presence of progression in diameter, left ventricular function and time interval after AVR were not helpful in determining a cumulative risk for developing dissection. Because dissection occurred in 4 of 18 patients (22%) with an ascending aorta diameter > 50 mm, it is suggested to consider replacement of the ascending aorta during AVR when a value of 50 mm is exceeded.