Comparison of TAVR With SAVR in Younger Low Surgical Risk Patients With Severe Aortic Stenosis

Inclusion Criteria: * Age 75 years or younger. * Severe calcific AS (Valve area \<1cm2 (or \<0.6 cm2/m2) AND one of the two following criteria: mean gradient \>40mmHg or peak jet velocity \>4.0m/s, OR in presence of low flow, low gradient with reduced or normal LVEF\<50%, a dobutamine stress echo should verify true severe AS rather than pseudo-AS * Symptomatic with angina pectoris, dyspnea or exercise-induced syncope or near syncope OR asymptomatic with abnormal exercise test showing symptoms on exercise clearly related to AS or systolic LV dysfunction (LVEF \<50%) not due to another cause. * Anticipated usage of biological aortic valve prosthesis. * Low risk for conventional surgery (STS Score \<4%). * Suitable for both SAVR and transfemoral TAVR. * Life expectancy \>1 year after the intervention. * Informed consent to participate in the study after adequate information about the study before randomization and intervention. Exclusion Criteria: * Coronary artery disease, not suitable for both percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG). * Coronary angiogram with a SYNTAX-score \>22. * LVEF \<25% without contractile reserve during dobutamine stress echocardiography. * Porcelain aorta, which prevents open-heart surgery. * Bicuspid valve with aorta ascendens diameter ≥45mm * Severe femoral, iliac or aortic atherosclerosis, calcification, coarctation, aneurysm or tortuosity, which prevents transfemoral TAVR. * Need for open heart surgery other than SAVR with or without CABG. * Myocardial infarction within last 30 days * Stroke or TIA within the last 30 days. NOTION-2, 01. February 2017, version 5 9 * Current endocarditis, intracardiac tumor, thrombus or vegetation. * Ongoing severe infection requiring intravenous antibiotics. * Unstable pre-procedural condition requiring intravenous inotropes or mechanical assist device (IABP, Impella) on the day of intervention. * Kidney disease requiring dialysis or severely impaired lung function (FEV1 and/or diffusion capacity \<40% of predicted). * Allergy to heparin, iodid contrast agent, warfarin, aspirin or clopidogrel.