Experimental data have demonstrated favourable effects of statins on endothelial progenitor cell (EPC) mobilization from the bone marrow, and cardiac homing. The purpose of the present prospective randomized controlled trial is to determine the effects of aggressive atorvastatin treatment (40 mg daily 2-weeks prior to surgery) on the number of endothelial progenitor cells (EPCs) after cardiopulmonary bypass by comparing with placebo.