The incidence of aortic stenosis is increasing due to the aging of the world-wide population and the lack of drug therapies to prevent, halt, or effectively slow the stenotic process. Transcatheter aortic valve replacement has become a viable alternative for treatment of severe symptomatic aortic stenosis in selected patients who are unsuitable candidates for surgical valve replacement. The Lotus Valve System is designed to enable precise placement and minimize or eliminate the paravalvular regurgitation and associated adverse events seen with earlier generation devices. The REPRISE I study assesses acute safety and performance.