Evaluation of Transcatheter Aortic Valve Replacement Compared to SurveilLance for Patients with AsYmptomatic Severe Aortic Stenosis

The study is evaluating the safety and effectiveness of the Edwards SAPIEN 3 Transcatheter Heart Valve (THV) in comparison with clinical monitoring in asymptomatic patients over the age of sixty five that have be diagnosed with severe calcific narrowing of the aortic valve (aortic stenosis). Patients will be determined asymptomatic with a negative stress test and must not demonstrate any of the following during and/or after the test. Fainting or pre-fainting episodes to including severe dizziness, chest pain, limiting shortness of breath or decreased exercise tolerance, lack of increase or drop in the top number on your blood pressure reading, or significant irregular heart beats greater or equal to four consecutive irregular heart beats. The physician may also determine the patient asymptomatic after a thorough assessment of patient history if the patient is unable to perform a stress test. The subjects vessels must be confirmed large enough for transfemoral access prior to being randomized to the 1:1 ratio to either receive transcatheter aortic valve replacement (TAVR) or clinical monitoring.