Global variability in bicuspid aortic valve morphology and aortopathy among patients with severe aortic stenosis referred for transcatheter valve implantation

Background While some studies have investigated the characteristics of patients from Asian versus European regions with bicuspid aortic valve (BAV) disease undergoing transcatheter aortic valve implantation (TAVI), geographic differences in a worldwide population remain poorly understood. The aim of our study was to evaluate the geographic differences of aortic valve morphology, annular size and associated aortopathy in a large, diverse population of India, West Europe, East Europe, Latin America, Middle East, Russia Commonwealth of Independent States, Asia Pacific and Africa patients with severe aortic stenosis (AS) referred for TAVI. Methods Data from cardiovascular multislice CT of severe AS patients referred for TAVI were analysed in a centralised core laboratory. Differences in valvular phenotype, annular size and aortic morphology were analysed with a focus on BAV patients. Results Among 12 712 patients evaluated, 3203 (25%) had BAV. These patients were more frequently male, younger and had larger annular area, aortic root diameters and higher prevalence of horizontal aorta (23% vs 10%, p<0.01) and severe calcifications (52% vs 32%, p<0.01). The highest prevalence of BAV was observed in patients from India (43%), with this group also being the youngest while the lowest was in patients from African regions (7%). Type 1 BAV was the most common (71%), followed by type 0 (26%) and type 2 (3%) subsets. Aortopathy was common across all geographic regions, but smaller aortic valve complex dimensions and lower coronary ostia height were seen in patients from India and the Asia-Pacific region. Eccentricity index and horizontal aorta were similar across different geographic regions. Conclusions BAV morphology and annular size showed significant heterogeneity based on the geographical origin. These differences may be relevant for procedural planning and anatomical assessment in BAV patients undergoing TAVI worldwide.