Epicardial pacemaker lead implantation. To identify the best position of left ventricular pacing sites, establishing anatomical orientations was critical. A: In the dorsal position, the right atrial appendage was confirmed by simply advancing the rigid endoscope toward the top of the pericardium. B: In the right lateral recumbent position, the left atrial appendage (LAA), distal of the coronary sinus (CS) and left circumflex artery (LCX) were clearly confirmed. C: By moving the rigid endoscope around the heart, the base of the postero-lateral wall of the left ventricle, the inferior vena cava (IVC) and the left pulmonary vein (LPV) were also identified. D: By pulling the rigid endoscopes toward the apex, a broad overview of the postero-lateral wall of the left ventricle, which was the appropriate epicardial pacing target in cardiac resynchronizing therapy, was obtained. E: The intraventricular pacing lead with a deflectable stylet was securely implanted in the postero-lateral wall of the left ventricle. F: The epicardial temporary pacing lead was implanted in the right ventricle (RV). G: An attempt was made to implant the epicardial sutureless pacing lead; however, the device was too large (14 mm) and required modifications. H: A suture attempt was successfully performed to fix the epicardial pacing leads. CS: coronary sinus; LAA: left atrial appendage; LCX: left circumflex artery; LPV: left pulmonary vein; LV: left ventricle; PD: posterior descending artery; RAA: right atrial appendage; RV: right ventricle.