We report about a 19 years old man, suffering from an cardiac arrest (ventricular fibrillation) caused by an ecstasy intoxication. A supraventricular tachycardia was recorded on day three after resuscitation. No pathological findings were demonstrated by coronary angiography. An slow- fast- av -nodal- reentry- tachycardia (AVNRT) was detected and successfully treated by electrical ablation of the slow pathway during electrophysiological mapping. No severe neurological deficits were found in discharge from hospital.