Mural endocarditis is an inflammation and disruption of the nonvalvular endocardial surface of the cardiac chambers. We present a rare case of mural endocarditis on the intraventricular (IV) septum on both the left and right ventricular side with intact valvular annulus. This case highlights the complexity of the operative and postoperative management in an unprecedented case of biventricular mural endocarditis.