Sapien 3 Transcatheter Aortic Valve Replacement in Young Aortic Valve Stenosis Patients From China

Inclusion Criteria: Subjects must meet ALL of the following inclusion criteria to be eligible for participation: * 50 years of age or older but ≤70 years old at time of consent. * Severe AS, defined as follows: a) For symptomatic patients: i) Aortic valve area ≤1.0 cm2 (or aortic valve area index of ≤0.6 cm2/m2), OR mean gradient ≥40 mm Hg, OR Maximal aortic valve velocity ≥4.0 m/sec by transthoracic echocardiography at rest b) For asymptomatic patients: i) Very severe AS with an aortic valve area of ≤1.0 cm2 (or aortic valve area index of ≤0.6 cm2/m2), AND maximal aortic velocity ≥5.0 m/sec, or mean gradient ≥60 mm Hg by transthoracic echocardiography at rest, OR ii) Aortic valve area of ≤1.0 cm2 (or aortic valve area index of ≤0.6 cm2/m2), AND a mean gradient ≥40 mm Hg or maximal aortic valve velocity ≥4.0 m/sec by transthoracic echocardiography at rest, AND an exercise tolerance test that demonstrates a limited exercise capacity, abnormal BP response, or arrhythmia OR iii) Aortic valve area of ≤1.0 cm2 (or aortic valve area index of ≤0.6 cm2/m2), AND mean gradient ≥40 mmHg, or maximal aortic valve velocity ≥4.0 m/sec by transthoracic echocardiography at rest, AND a left ventricular ejection fraction \<50%. * Tricuspid aortic valve stenosis and type-1 bicuspid aortic valve anatomy confirmed by MDCT. * The subject and the treating physician agree that the subject will return for all required post-procedure follow-up visits. * Adequate iliofemoral access and acceptable l…