A 75-year-old male with a previous history of coronary artery bypass grafting (LITA-LAD, RITA-RA-4PD-14PL) was referred to our hospital for congestive heart failure. Cardiac workup revealed severe ischemic mitral regurgitation which required surgical correction. His preoperative coronary arterial computed tomography demonstrated total occlusion of both orifices of the native coronary arteries, and the complete dependence of his myocardial blood supply on the patent bypass grafts without any evidence of ischemia. Therefore, antegrade cardioplegia could not be applied for cardiac protection during the procedure. Continuous retrograde cardioplegia was planned to be applied in a case where both arterial grafts could be dissected and clamped whereas systemic hyperkalemia and mild hypothermia would be applied in case where the clamp would be impossible. Intraoperatively, both arterial grafts could be dissected and clamped and we performed mitral annuloplasty and tricuspid annuloplasty using continuous retrograde cardioplegia. The patient could be weaned off cardiopulmonary bypass without difficulty, and his postoperative course was uneventful. We conclude that continuous retrograde cardioplegia is a safe and viable option, especially when antegrade cardioplegia is not securely delivered due to an occluded coronary ostia.