Time-consuming and complex cardiac surgery remains a challenge in patients with impaired ventricular function and consequently necessary prolonged cardioplegic arrest may jeopardize a fragile myocardial status. The case is reported of a 63-year-old male patient with low left ventricular ejection fraction (LVEF) and history of refractory cardiac failure who successfully underwent a beating heart aortic and mitral valve replacement through a superior biatrial septotomy. Technical considerations and advantages related to this specific surgical access combined with a beating heart approach are discussed.