• Images in cardiology

A fetus presenting at 34 weeks’ gestation with hydrops was diagnosed to have a supraventricular tachyarrhythmia with associated multiple intracardiac rhabdomyomas. After delivery, the patient still suffered from supraventricular tachyarrhythmia and was treated with several antiarrhythmic agents, but without success. At the age of 7 months, there was one large residual tumour on the left atrial aspect of the anterior mitral valve leaflet (panel A), with associated pre-excitation and re-entrant supraventricular tachyarrhythmia suggestive of a left sided pathway. During electrophysiology study, catheter ablation was performed retrogradely, on the ventricular aspect of the tumour, with termination of pre-excitation and non-inducibility of tachyarrhythmia. Echocardiography performed 24 hours later also demonstrated morphologic alteration in the tumour, with development of a large central echolucent area (panel B). At follow up eight weeks later, the patient remained without symptoms. We provide a correlation between catheter ablation, disappearance of pre-excitation, and change in tumour morphology, suggesting that the tumour was indeed the accessory pathway.