Strategies to Prevent Transcatheter Heart Valve Dysfunction in Low Risk Transcatheter Aortic Valve Replacement

Inclusion Criteria: * Severe, degenerative AS, defined as: * Mean aortic valve gradient ≥40 mm Hg OR Vmax ≥4 m/sec AND * Calculated aortic valve area ≤1.0 cm2 OR aortic valve area index ≤0.6 cm2/m2 * Symptomatic AS, defined as a history of at least one of the following: * Dyspnea that qualifies at New York Heart Association (NYHA) class II or greater * Angina pectoris * Cardiac syncope * The Heart Team agrees that the patient is low-risk, quantified by an estimated risk of death ≤3% by the calculated STS score for operative mortality at 30 days; AND agrees that SAVR would be an appropriate therapy if offered * A surgeon who is experienced in Surgical Aortic Valve Replacement (SAVR) has spoken with the patient in person and stipulates that the patient understands his/her alternatives for FDA approved therapy, including open heart surgery to replace their aortic valve * The institutional Heart Team determines that transfemoral TAVR is appropriate * Aortic valve anatomy and dimensions suitable for TAVR using a commercially available valve * Iliofemoral artery anatomy and dimensions suitable for transfemoral TAVR using a commercially available valve and delivery system * Procedure status is elective * Expected survival is at least 24 months Exclusion Criteria: * Subject unable or unwilling to give informed consent * Concomitant disease of another heart valve or the aorta that requires either transcatheter or surgical intervention * Any condition that is considered a contraindication for placement of a bioprosthetic aortic valve (e.g. patient requires a mechanical aortic valve) * Aortic stenosis secondary to a bicuspid aortic valve * Prior bioprosthetic surgical aortic valve replacement * Mechanical heart valve in another position * End-stage renal disease requiring hemodialysis or peritoneal dialysis, or a creatinine clearance \<20 cc/min * Left ventricular ejection fraction \<20% * Recent (\<6 months) history of stroke * Symptomatic carotid or vertebral artery disease, or recent (\<6 weeks) surgical or endovascular treatment of carotid stenosis * Any contraindication to oral antiplatelet or anticoagulation therapy following the procedure, including recent or ongoing bleeding, or HASBLED score \>3 (Table 2 - HASBLED scoring system) * Severe coronary artery disease that is unrevascularized * Recent (\<30 days) acute myocardial infarction * Patient cannot undergo transfemoral TAVR for anatomic reasons (as determined by supplemental imaging studies); this would include inadequate size of iliofemoral access vessels or an aortic annulus size that is not accommodated by the commercially available valves * Any comorbidity not captured by the STS score that would make SAVR high risk, as determined by a cardiothoracic surgeon who is a member of the heart team; this includes: * Porcelain or severely atherosclerotic aorta * Frailty * Hostile chest * Internal mammary artery or other conduit either crosses midline of sternum or is adherent to sternum * Severe pulmonary hypertension (PA systolic pressure \> 2/3 of systemic pressure) * Severe right ventricular dysfunction * Ongoing sepsis or infective endocarditis * Severe chronic obstructive pulmonary disease, as demonstrated by forced expiratory volume (FEV1) \<750 cc * Liver failure with Childs class C or D * Pre-procedure shock, inotropes, mechanical assist device, or cardiac arrest * Pregnancy or intent to become pregnant prior to completion of all protocol follow-up procedures * Known allergy to warfarin or aspirin