The long QT syndromes have been classified into acquired or inheritary forms, both of which are associated with a characteristic type of life-threatening polymorphic ventricular tachycardia called torsade de points. Beta-adrenergic blocker is the first cholic treatment, but in those whom cardiac events are not prevented by $eta$-blockade, left thoracic sympathetic ganglionectomy may be useful in selected cases. A 50-year-old woman had an recurrent syncopal attack in which she was unconscious for 1-2 min and 1-2 times a month for 10 years. The EKG revealed that QT & QTc intervals were 744 and 632 msec respectively. Treatment with Beta-adrenergic blocker and calcium channel blocker was ineffective in preventing recurrence of syncopal spell. Therefore, she underwent left thoracic sympathetic ganglionectomy with thoracoscope. During the 9 months after operation, she was free of syncopal episodes and is doing well.