Vegetative electrode infection after implantation of permanent pacemaker or defibrillator is an uncommon but a serious complication. Diagnosis of the lead infection is particularly important since surgical manipulation is usually required for its treatment. We present 3 cases of electrodes related infective endocarditis among the 154 patients who implanted pacemaker or defibrillator between 2001 and 2004 in Korea university hospital. These complications were difficult to diagnose because of ambiguous clinical manifestations and indeterminate transthoracic echocardiographic (TTE) findings and were finally confirmed by transesophageal echocardiography (TEE).