Explanted Ventak PRx implantable cardioverter defibrillator, model no. 1705, serial no. PG 660501, by Cardiac Pacemakers Inc, St. Paul's, Minnesota, USA, from St George's Hospital, Tooting, 1992-3

‘Sudden Cardiac Death’ (SCD) is an unexpected death due to cardiac causes which occurs in a short time period. It accounted for one death every minute in the US in 1991. The Explanted Ventax Prx Implantable Cardioverter Defibrillator is a type of pacemaker developed in the same year. It was designed at St. George's Hospital, London, specifically to tackle SCD and was made in the US by Cardiac Pacemakers Incorporated. It was implanted into the chest cavity of individuals at risk of SCD due to a previous heart attack or a pre-existing heart condition. The cardiac defibrillator stayed dormant once implanted until a cardiac abnormality occurred. It then emitted regulated electrical impulses. These stimulate the contraction of the heart muscles to provide a sufficient rate of heartbeat.