Bicuspid aortic valves (BAVs) are associated with ascending aortic aneurysms. We studied BAV patients before and after aortic valve replacement (AVR) to determine the risk and predictors of aortic root dilatation after surgery. BAV patients (n=60) with an aortic root <or=45 mm who underwent AVR were followed by echocardiography (6.2+/-2 years) and aortic root measured. No statistical difference was found between the preoperative and postoperative diameter of the aortic root as well as association with the variables studied. The use of statins or beta-blockers did not affect the follow-up on the aortic root diameter. Preoperative aortic root diameter between patients who died due to cardiovascular cause in the long-term did not vary when compared with those who survived. Even though the numbers of patients studied is low to make any kind of conclusions, our study permits us to suggest that AVR prevents aortic root dilation in BAV patients whose aortic root diameter at time of surgery was <or=45 mm.