Optimized Expansion of the implanted transcatheter aortic valve to reduce hypoattenuating leaflet thickening in non-atrial fibrillation patients undergoing transcatheter aortic valve implantation (TAVI): an international, multicentre, randomized controlled trial. The objective is to evaluate whether TAVI with systematic optimized pre- and post-dilatation (optimized expansion (OptEx) TAVI strategy), compared to a standard of care (SoC) TAVI strategy, is superior in reducing hypoattenuating leaflet thickening as evaluated by cardiac computed tomography (CT) imaging at three months after TAVI. The primary outcome is at least one thickened TAV leaflet involving ≥ 25% of the leaflet curvilinear dimension as assessed at cardiac CT at three months after TAVI.