[Chronic left ventricular epicardial pacing by the perforated endocardial electrode through the cardiac vein].

We report a rare complication of endocardial pacing electrode implantation. A 64-year-old man, who was implanted transvenous pacemaker system by the other hospital one month ago, visited our outpatient clinic with the complaint of diaphragmatic twitching. Left ventricular pacing was highly suspected because of right bandle branch block pattern by 12 leads ECG. Pericardial effusion was observed by echocardiography, and angiography revealed the pacing electrode coursing through the coronary sinus and perforated the cardiac vein towards the posterior wall of the left ventricle. A new generator and a pacing electrode were implanted on the other side. Pericardial drainage was not performed because hemodynamics was stable. The patient discharged hospital on 18th postoperative day without any complication.