Timely diagnosis of convulsive syncope can avert imminent death

Editor – Timely diagnosis of convulsive syncope is crucial to the correct management of underlying causes such as implantable defibrillator malfunction,¹ long QT syndrome,² and Brugada syndrome,³ which may present with self-limiting ventricular tachyarrhythmia.^1–3 Timely identification of convulsive syncope becomes a diagnosis of immediate life-saving importance when ventricular tachyarrhythmia is no longer self-limiting, and the window of opportunity for successful defibrillation is narrow and finite, as was the case in 50% of 14 young athletes aged 14–17, in whom potentially irreversible exercise-related ‘collapse’ was associated with convulsive syncope.⁴ In the same study, similar brief seizure-like activity was noted in 13% of 22 older persons aged 42–71 who collapsed within range of defibrillators installed on that high school campus.⁴ One of the conclusions from that study was that, in young athletes ‘brief myoclonic activity after collapse… could be mistaken for a seizure’, especially if rescuers mistook agonal or occasional gasping for normal breathing, and if they falsely identified the presence of a pulse.⁴ Accordingly, the opportunity to make a rapid life-saving diagnosis can only be optimised by heightened awareness of the entity of convulsive syncope even where ventricular tachyarrhythmia might not be self-limiting and by heightened awareness that rescuers may fail to recognise sudden death as a ‘signature’ of that subtype of ventricular tachyarrhythmia when they misidentify the pulse,⁴ or when they mistake agonal gasping for normal breathing.^4,5

• © 2010 Royal College of Physicians