Cardiac MRI for Severe Aortic Stenosis

Inclusion Criteria: * 18 years of age or older * Severe symptomatic aortic stenosis (estimated aortic valve area \<1 cm2) 1,2 as documented on a transthoracic echocardiogram (ECG) performed within 4 months prior to enrollment * Planned for AVR within 8 weeks after enrollment * Able to have a cardiac MRI within 3 weeks prior to the AVR surgery * A preoperative coronary angiography demonstrating the absence of hemodynamically-significant CAD in need of revascularization during AVR surgery * Able to tolerate cardiac MRI with gadolinium contrast as required by protocol, to be performed at an ACRIN-qualified facility using an ACRIN-qualified MR scanner * Willing and able to provide a written informed consent Exclusion Criteria: * Not suitable to undergo cardiac MRI or use the contrast agent gadolinium because of: * Claustrophobia * Presence of metallic objects or implanted medical devices in body (i.e., implanted cardiac pacemaker or defibrillator, central nervous system aneurysm clips, implanted neural stimulators, cochlear implant, ocular foreign body \[e.g., metal shavings\], other implanted medical devices \[e.g., drug infusion port\], insulin pump, surgical clips, prostheses, artificial hearts, valves with steel parts, metal fragments, shrapnel, tattoos near the eye, or steel implants) * Weight greater than that allowable by the MRI table * Known LV ejection fraction \<50% * Previous aortic valve surgery * Planned additional valve repair/replacement * Infective endo…