Bicuspid aortic valve disease: advancements and challenges of transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) has revolutionized the treatment of patients with severe aortic stenosis (AS). Initially developed for patients with tricuspid aortic valve (TAV) anatomy, the procedural success and expanding indications of TAVI have spurred interest in its application to more complex aortic valve anatomies, such as the bicuspid aortic valve (BAV). The growing interest in this specific sub-set of patients with AS is driven by the recent extension of TAVI indications to younger individuals, who exhibit a notably higher incidence of bicuspid anatomy compared with older populations. Bicuspid aortic valves present distinct anatomical and pathological complexities that pose significant challenges to the conventional TAVI approach. These include asymmetric calcification, aortic root dilation (also known as BAV aortopathy), and variations in cusp fusion patterns, which can affect valve deployment, transcatheter heart valve sealing, and long-term durability. Despite these challenges, advancements in imaging techniques, valve design, and procedural strategies have led to increased adoption of TAVI in BAV patients. However, surgical aortic valve replacement still retains a more prominent role in this group compared with patients with TAVs. This preference is partly due to the exclusion of BAV patients from almost all previous randomized controlled trials, which limits the available evidence supporting the use of TAVI in this unique cohort. This state-of-the-art review aims to provide a comprehensive overview of the current landscape of TAVI in BAV patients, including an analysis of anatomical considerations and procedural pitfalls, as well as outcomes' improvements with new device iterations. It will also explore clinical data, tackling the risks, benefits, and the evolving role of TAVI in this unique patient cohort.