Clinical classification of cardiac deaths

Abstract

One hundred forty-two deaths among 743 men ages 50-65 years who had been examined and followed 5-10 years were investigated and classified on the basis of clinical information from medical and non-medical observers, ECGs and autopsies. A classification based on the condition of the circulation immediately before death appears to be most relevant to studies of sudden death. In 58% of the cases, the subject collapsed abruptly and his pulse ceased without prior circulatory collapse (arrhythmic death); in 42%, the pulse ceased only after the peripheral circulation had collapsed (deaths in circulatory failure). Thirty-three percent of arrhythmic deaths and 10% of deaths in circulatory failure occurred in a setting of clinical evidence of acute ischemic heart disease (p < 0.005). Forty-five percent of arrhythmic deaths were preceded by chronic congestive heart failure without circulatory collapse. Ninety-three percent of final illnesses that lasted less than 1 hour ended in arrhythmic deaths; 74% that lasted more than 1 day ended in deaths in circulatory failure (p < 0.001). Eight-eight percent of deaths that occurred outside of the hospital were arrhythmic; 71% of deaths that occurred in the hospital were deaths in circulatory failure (p < 0.001). Ninety percent of deaths in which the primary cause of the final illness was heart disease were arrhythmic; 86% of deaths in which the primary cause was other than heart disease were deaths in circulatory failure (p < 0.001). Ninety-one percent of deaths precipitated by an acute cardiac event were arrhythmic; 98% precipitated by acute respiratory obstruction, hemorrhage, infection, stroke or other noncardiac events were deaths in circulatory failure (p < 0.001).