In recent years, the popularity of simplified intraoperative ablation approaches to treat atrial fibrillation (AF) has been progressively increasing. Our group has described a left atrial procedure based on epicardial radio frequency ablation on cardiopulmonary bypass (CPB). We report our CPB and myocardial protection strategy in 157 patients who underwent AF ablation combined with open-heart surgery from February 1998 to February 2002. Since epicardial ablations are performed on CPB on the beating heart, the CPB strategy is crucial. Total normothermic CPB allows a safe dissection around the pulmonary veins on the decompressed heart; after the ablating catheter has been positioned, an adequate filling of the left atrium favours a uniform contact with the atrial wall. After crossclamping, low-flow retrograde cardioplegia delivery is administered while ablating endocardially to protect the main coronary arteries in the atrio-ventricular groove from radio frequency-related trauma. All patients were successfully weaned from CPB. Sinus rhythm was restored in 152 of 157 (96.8%) patients immediately after surgery. No procedure-related complications were recorded. Epicardial ablations allowed us to reduce significantly the aortic crossclamping time required for ablations. The conduct of CPB and myocardial protection play a central role in the surgical strategy by improving intraoperative feasibility and effectiveness of radio frequency ablation and preventing some of the potential postoperative complications related to the procedure.