Junctional ectopic tachycardia (JET) has been observed in up to 11.4% of pediatric patients after cardiac surgery and is the most common tachyarrhythmia during the early postoperative period. 1 Following surgery, the heart is vulnerable to the negative effects of a high heart rate and atrioventriular (AV) asynchrony, which can lead to hemodynamic instability, decreasing cardiac output. Accurate identification of JET is critical because it is not amenable to synchronized cardioversion and is an important factor in postoperative morbidity. 1 The following case is an example of the cardioversion attempt of a perfusing tachyarrhythmia mistakenly identified as supraventricular tachycardia (SVT).
A 5-month-old, 8.7-kg, female infant underwent surgical treatment of complete atrialventricular septal defect with a common atrium, left-looped ventricles, pulmonary atresia with confluent pulmonary arteries, and dextrocardia. A Glenn shunt and AV valvuloplasty was performed with a cardiopulmonary bypass time of 225 minutes and aortic cross-clamp time of 47 minutes....