Examination of Valve Insufficiency Before and After MitraClip or TAVI Procedure by 3D Echocardiography Compared to MRI

Inclusion Criteria: * patients with severe symptoms of an aortic stenosis who underwent catheter based implantation of an aortic valve * patients who are planned to undergo a reconstruction of the mitral valve with the MitraClip System * Patients who are aged above 18 years and legally competent * signed informed consent Exclusion Criteria: * patients with previous myocard infarction, previous heart surgeries, malignity or valvular abnormities \> stage 1 * patients with atrial fibrillation * pregnant and breast-feeding women * patients with disturbed central nerve system * patients with pacemaker, implants, ferrous clamps,insulin pump * patients with tattoo * patients with claustrophobia * patiens with asthma