Purpose: To report the management of junctional ectopic tachycardia af
ter cardiac surgery in an infant. Postoperatively, the patient suffere
d profound cardiac decompensation secondary to the accelerated rhythm
and required extracorporeal membrane oxygenation (ECMO) for haemodynam
ic support. Clinical features: A 14-day-old, 3.5 kg boy exhibited junc
tional ectopic tachycardia after cardiopulmonary bypass. Left atrial p
ressure was 25-28 mmHg. No impact on the tachycardia was seen after ra
pid overdrive atrial pacing or after 20 mu g fentanyl iv, 45 mu g digi
talis, 100 mg magnesium or procainamide (loading dose 15 mg, then 30 m
g.k(-1).min(-1)). Active cooling decreased the nasopharyngeal temperat
ure to 35.2 degrees C, when the heart rate decreased below 180 bpm wit
h a left atrial pressure of 8-10 mmHg. Dopamine (2 mu g.kg(-1).min(-1)
) and dobutamine (5 mu g.k(-1).min(-1)) were added to improve the card
iac output, Sodium nitroprusside (0.25 to 1 mu g.k(-1).min) maintained
the systolic pressure < 100 mmHg. On arrival in ICU, heart rate incre
ased to 200 bpm. The patient received cardiac massage for severe hypot
ension 75 min after surgery. Emergency ECMO was instituted for circula
tory support. Procainamide, digoxin, dopamine, dobutamine, sodium nitr
oprusside and hypothermia were continued. Sinus rhythm resumed on the
first postoperative day, but procainamide and induced hypothermia at 3
4 degrees C were maintained for 36 hr after normalization of the rhyth
m to prevent recurrence of the tachycardia, Total duration of ECMO was
three and a half days, Recovery was uneventful. Conclusion: The use o
f ECMO, as a first line of defence, is suitable for the emergency supp
ort of patients with JET because of the ease of support of circulation
and precise control of hypothermia.