In this prospective, randomized, multicenter, open-label interventional clinical trial, the investigators' aim to test the effect of Cardiac Resynchronization Therapy (CRT) in cases of new-onset and persistent Left Bundle Branch Block (LBBB) occurring in the context of Transcatheter Aortic Valve Implantation (TAVI), in patients with moderately reduced left ventricular systolic function (35% \< EF \< 55%). The investigators hypothesize that in patients with persistent LBBB developing after TAVI and mildly reduced left ventricular systolic function (35% \< EF \< 55%), early postoperative CRT implantation favorably influences the process of myocardial reverse remodeling by reducing electromechanical dyssynchrony, thereby decreasing the combined endpoint of heart failure-related hospitalizations and mortality at one year.