Characteristics of Bicuspid Aortic Valve Disease and Stenosis: The National Echo Database of Australia.

Background Bicuspid aortic valve (BAV) is the most common congenital heart disease in adults but is clinically heterogeneous. We aimed to describe the echocardiographic characteristics of BAV and compare patients with BAV with moderate-to-severe aortic stenosis (AS) with those with tricuspid aortic valve (TAV) stenosis. Methods and Results Using the National Echo Database of Australia, patients in whom BAV was identified were studied. Those with moderate-to-severe AS (mean gradient >20 mm Hg [BAV-AS]) were compared with those with TAV and moderate-to-severe AS (TAV-AS). Of 264 159 adults whose aortic valve morphology was specified, 4783 (1.8%) had confirmed BAV (aged 49.6±17.4 years, 69% men). Of these, 42% had no AS, and 46% had no aortic regurgitation. Moderate-to-severe AS was detected in a greater proportion of patients with BAV with a recorded mean gradient (n=1112, 34%) compared with those with TAV (n=4377, 4%; <0.001). Patients with BAV-AS were younger (aged 55.3±16.7 years versus 77.3±11.0 years; <0.001), and where measured had larger ascending aortic diameters (37±8 mm versus 35±5 mm; <0.001). Age and sex-adjusted mortality risk was significantly lower in patients with BAV-AS (hazard ratio, 0.53; 95% CI, 0.45-0.63; <0.001). Conclusions In this large study of patients across the spectrum of BAV disease, the largest proportion had no significant valvulopathy or aortopathy. Compared with those with TAV-AS, patients with BAV were more likely to have moderate-to-severe AS, have larger ascending aortas, and were over 2 decades younger at the time of AS diagnosis. Despite this, patients with BAV appear to have a more favorable prognosis when AS develops, compared with those with TAV-AS. Registration URL: www.anzctr.org.au/; Unique identifier: ACTRN12617001387314.