Right atrial rhabdomyoma acting as the substrate for Wolff-Parkinson-White syndrome in a 3-month-old infant.

We report a 3-month-old infant girl who presented with supraventricular tachycardia, who was detected to have a large right atrial rhabdomyoma and evidence of Wolff-Parkinson-White (WPW) syndrome with an accessory pathway corresponding to the position of the tumour. In view of the resistant cardiac arrhythmia and large size of the tumour, the infant underwent surgical excision of the tumour. The evidence of WPW syndrome disappeared from the surface electrocardiogram immediately upon removal of the tumour.