A 60 year old woman presented to the emergency department after four episodes of seizure. She had already experienced two repeated episodes during the past year before admission. The physical examination, including a complete neurological examination, was normal. Despite an intravenous infusion of clonazepam, another episode of seizure occurred with unresponsiveness and tonic–clonic movements followed by post-ictal confusion. The computed tomography of the head was normal. An electroencephalogram was then performed. During this recording, another episode of seizure occurred. As shown in the panel below, a polymorphic ventricular tachycardia (VT) started before any change of the electroencephalogram. The electrocerebral activity then showed an increasing amplitude followed at 14 seconds by a flattening and slowing activity (below). The polymorphic VT spontaneously resumed after 56 seconds (right panel). A long QT syndrome was diagnosed. β Blocker treatment was started and a defibrillator implanted.

This recording demonstrates that a proven seizure can be related to a spontaneous polymorphic VT. This reinforces the idea that cardiac issues should be systematically considered in patients with a diagnosis of epilepsy remaining uncertain.