Factors Related to the Need for Surgery after the Diagnosis of Bicuspid Aortic Valve: One Center´s Experience under a Conservative Approach

Background and Aim: Bicuspid aortic valve (BAV) increases the risk of aortic valve dysfunction and ascending aorta aneurysm and, consequently, the need for aortic valve replacement and/or aortic repair. However, there is no universal consensus about the surgical criteria and the predictors for surgery. The aim of this study was to investigate related factors to the need for surgery in the setting of a strict long-term follow-up with relatively conservative surgical criteria. Methods: We prospectively followed 120 patients after the diagnosis of BAV. Predisposing factors for a future need for aortic valve replacement and ascending aorta repair were assessed. Aortic surgery was indicated when the ascending aorta diameter was ≥55 mm and was recommended based on patient characteristics and in the presence of a severe aortic valve dysfunction with an aortic diameter ≥50 mm. Results: During follow-up (mean, 86 months), 34 patients (28%) (mean age, 56±12 years) were surgically treated. Aortic valve dysfunction (n=22; 64%) and ascending aorta dilatation (n=12; 36%) were the indications for surgery. Aortic regurgitation was the most frequent valve dysfunction at the time of diagnosis for BAV, but aortic stenosis was the most frequent indication for surgery. The presence at surgery of either aortic regurgitation or stenosis was clearly related to age, with regurgitation predominating in patients under 55 years, and aortic stenosis in older patients. Multivariate Cox analysis showed that aortic stenosis (hazard ratio 4.1, p=0.001), indexed ascending aorta dilatation (hazard ratio 3.0, p=0.03) and left ventricular end-diastolic diameter ≥60 mm (hazard ratio=4.0, p=0.01) at diagnosis were factors associated with future surgery. Aortic dissection was not observed in patients that did not undergo surgery. Conclusions: A relatively conservative approach for the indication of ascending aortic surgery in BAV is safe. In this setting, the presence of aortic or left ventricle dilatation and aortic stenosis at diagnosis of BAV were predictive of the need for surgery in the follow-up.