A 23-year-old woman presented with multiple episodes of palpitations and loss of consciousness within a 48 h period. She gave a history of similar episodes since childhood and had been previously diagnosed as suffering from epilepsy. While being monitored in the hospital, she was found to have rapid polymorphic ventricular tachycardia (PVT) during the episodes. She required repeated cardioversion as the arrhythmia recurred despite administration of intravenous amiodarone and lignocaine. Prolonged monitoring showed frequent premature ventricular complexes (PVC) (figure 1A), couplets and short runs of ventricular tachycardia (figure 1B) and longer runs of ventricular tachycardia, which were associated with her clinical symptoms (figure 1C). Echocardiography showed no structural …