Wordnet 3.0
NOUN (1)
1. 
 absence of systole; 
 failure of the ventricles of the heart to contract (usually caused by ventricular fibrillation) with consequent absence of the heart beat leading to oxygen lack and eventually to death; 
[syn: asystole, cardiac arrest, cardiopulmonary arrest]
WordNet (r) 3.0 (2006):
cardiopulmonary arrest
    n 1: absence of systole; failure of the ventricles of the heart
         to contract (usually caused by ventricular fibrillation)
         with consequent absence of the heart beat leading to oxygen
         lack and eventually to death [syn: asystole, cardiac
         arrest, cardiopulmonary arrest]