A newborn with long QT interval and repetitive ventricular tachycardia of the "torsade de pointes" type was seen at the age of one day. The arrhythmia was resistant to lidocaine, propranolol and atropine, but was controlled by isoproterenol infusion. A transvenous pacemaker, inserted at three days of age, suppressed the ventricular tachycardia at stimulation rates above 110/minute. At 19 days of age a permanent pacemaker at pulse rate of 119 beats/minute was implanted. At one year of age the infant was thriving and was completely free of ventricular arrhythmia.