The efficacy of continuous warm blood cardioplegia (CWBC) and intermittent cold potassium cardioplegia (ICPC) was compared in 49 patients who underwent cardiac valve re-replacement; 27 patients received CWBC and 22 received ICPC. During surgery, a narrower dissection of the heart was used in CWBC patients. Postoperative recovery of left ventricular function was significantly better in the CWBC group than in the ICPC group. Postoperatively, maximum serum creatine kinase-MB levels were significantly lower in CWBC patients. Perioperatively, myocardial oxygen and lactate extractions were maintained within the normal range in CWBC patients but were clearly impaired in ICPC patients. Thus, CWBC provides greater myocardial protection, without wide exposure of the heart, in cardiac valve re-replacement.