Implantation of a transvenous endocardial pacemaker is contraindicated in patients with a mechanical tricuspid valve. An epicardial left ventricular pacemaker lead was placed by a transvenous route through the coronary sinus into the lateral cardiac vein in a 58-year-old woman with mechanical aortic, mitral, and tricuspid valves, for permanent pacing due to chronic atrial fibrillation with a slow ventricular rate accompanied by syncope. This lead was then connected to a single-chamber pacemaker. The patient had no problem in the following three months. Placement of an epicardial pacing lead through the coronary sinus provides a safe and effective pacing in patients with a mechanical tricuspid valve, thus obviating major cardiac surgery.