Local or general anesthesia is essential for safe operation. Patients in good preoperative condition are relatively to tolerable to the operation, but the patients in poor preoperative condition have the high mortality and morbidity during and after the operation. Therefore, we should choose the anesthetic agents and methods, which cause little effect to the patient's life. Among the intraventricular blocks, bundle branch is the most common type, and left bundle branch block may progress to a more serious condition of complete heart block. Optimal anesthetic management of patients with cardiovascular disease requires a thorough knowledge of normal cardiac physiology, the circulatory effects of the various anesthetic agents, and the pathophysiology and treatment of these diseases. The authors successfully performed balanced anesthesia in operation of a 63 year old female patient who showed complete left bundle branch block pattern in a preoperative electrocardiographic tracing without any subjective symptoms.