Sinus node reentrant tachycardia in a neonate.

A neonate presented with paroxysmal atrial tachycardia. Transesophageal electrophysiological study demonstrated sinus node reentrant tachycardia, which was induced and terminated with programmed electrical stimulation. The tachycardia would also terminate in the atrium with adenosine. Empiric digoxin treatment successfully suppressed the tachycardia which then recurred with discontinuation of the digoxin at 6 weeks. The child was retreated with digoxin with no further recurrences for 18 months. Transesophageal electrophysiological study at 20 months showed prolonged sinus node recovery times and no inducible arrhythmias. The child has remained free of arrhythmias at 4 years.