The aconite root has been used in oriental medicine to improve metabolism of debilitated patient and to cure acute dysuria, cardiac weakness, gout, neuralgias and rheumatism. The crude drug "bu-shi" or "cho-oh", which is obtained from the Aconitum roots, contains the potent poisons aconitine, mesaconitine, jesaconitine, and hypaconitine, which are C diterpenoid ester alkaloids. These alkaloids have been known to induce fatal cardiac arrhythmias, such as ventricular tachycardia or fibrillation, cardioversion/defibrillation are the most effective treatment of choice to terminate reentrant arrhythmias. Through animal experiments, it has been known that repeated delivery of high energy DC shock cause some myocardial damage, and the severity of myocardial damage is proportional to the delivered energy. The paddle size, defibrillatin interval and total delivered energy have also been known to be associated with the severity of injury. But in humans, the amount of energy that cause myocardial damage or dysfunction has not been studied. Therefore it is necessary that a quantitative study on this issue in conjunction with the amount of each delivered energy and the interval between electrical shock should be done. We experienced a 36 year old man who complained nausea, vomiting, dizziness and generalized weakness and showed hemodynamic compromise with recurrent ventricular tachyarrhythmias such as bidirectinal ventricular tachycardia, Torsades de pointes and ventricular fibrillation. This patient was resuscitated with repeated cardioversion/defibrillation of 20,680 Joules for 8 hours and 30 minutes, but did not show significant myocardial damage.