Biological Factors Associated With Subclinical Valvular Thrombosis

A prospective, multicentric cohort study including 166 patients with symptomatic aortic stenosis treated with transcatheter aortic valve implantation (TAVI). \- The main objective is to determine whether the high residual platelet reactivity rates in patients undergoing TAVI is associated with the occurrence of clinical and / or subclinical prosthetic valve thrombosis measured by echocardiography and multi-slice computerized tomography

Inclusion Criteria: * Patients with severe symptomatic aortic stenosis who it was accepted to be treated with TAVI by a multidisciplinary team "Heat Team". * TAVI was successfully implanted (according to Valve Academic Research Consortium II criteria) and are under treatment with double antiplatelet therapy. * Signed informed consent to participate in this study. Exclusion Criteria: * Age under 18 years and pregnant or of childbearing age. * Acute Recent stroke recent \