Effect of Antifibrotic Therapy on Regression of Myocardial Fibrosis After Transcatheter Aortic Valve Implantation (TAVI) in Aortic Stenosis Patients With High Fibrotic Burden

The aim of the study is to evaluate the effect of antifibrotic therapy on regression of myocardial fibrosis after TAVI in patients with baseline high fibrotic burden. Therefore, patients will be treated with Spironolactone in addition to standard of care, Spioronolactone + Dihydralazine in addition to standard of care or according to standard of care alone without any study medication. First, differences between patients in the control arm and patients randomized to anti-fibrotic therapy will be analyzed. The second analysis will determine, whether dihydralazine medication in addition to spironolactone is able to increase a potential antifibrotic effect. Myocardial fibrosis will be assessed by cardiac magnetic resonance imaging (CMR) before TAVI and 1 year after. Quantification of potentially irreversible replacement fibrosis will be carried out by late gadolinium enhancement (LGE), and quantification of the potentially reversible diffuse interstitial fibrosis will be performed by measurement of the extracellular volume fraction (ECV), thereby deriving matrix volume and cell volume.