SUDDEN CARDIAC DEATH TRIGGERED BY AN EARTHQUAKE

Background. The earthquake that struck the Los Angeles area at 4:31 a. m. on January 17, 1994, was one of the strongest earthquakes ever reco rded in a major city in North America. Once the life-threatening situa tion was over, the Northridge earthquake, so called because its epicen ter was near Northridge, California, just north of Los Angeles, provid ed investigators an unusual opportunity to examine the relation betwee n emotional stress and sudden cardiac death. Methods. We reviewed the records of the Department of Coroner of Los Angeles County for the wee k before the earthquake, the day of the earthquake, the six days after the earthquake, and corresponding control periods in 1991, 1992, and 1993. Results. On the day of the earthquake, there was a sharp increas e in the number of sudden deaths from cardiac causes that were related to atherosclerotic cardiovascular disease, from a daily average (+/-S D) of 4.6+/-2.1 in the preceding week to 24 on the day of the earthqua ke (z=4.41, P<0.001). Sixteen victims of sudden death either died or h ad premonitory symptoms, usually chest pain, within the first hour aft er the initial tremor. Only three sudden deaths occurred during or imm ediately after unusual physical exertion. During the six days after th e earthquake, the number of sudden deaths declined to below the base-l ine value, to an average of 2.7+/-1.2 per day. Conclusions. The Northr idge earthquake was a significant trigger of sudden death due to cardi ac causes, independently of physical exertion. This finding, along wit h the unusually low incidence of such deaths in the week after the ear thquake, suggests that emotional stress may precipitate cardiac events in people who are predisposed to such events. (C) 1996, Massachusetts Medical Society.