Three infants with junctional automatic ectopic tachycardia (JET) were seen over an 8-month period. Each had decreased left ventricular function. Two were treated with amiodarone, which together with propranolol reduced the tachycardia rate 10 to 40 bpm, but did not result in sinus rhythm. One patient died suddenly at home, as had 50% of our patients with JET treated with conventional medication. Two patients were treated by transcatheter ablation of the bundle of His and implantation of an atrial synchronous pacemaker. Neither has had subsequent tachycardia or required drugs. One patient resumed sinus rhythm and does not use his pacemaker. The other patient has complete AV block and continues to use her pacemaker. This aggressive approach to this lethal dysrhythmia offers hope for prevention of the former bad prognosis.