Outcome after cardiac arrest during acute myocardial infarction.

A community-wide study of acute myocardial infarction (AMI) was conducted in all 16 acute-care general hospitals in the Worcester, Massachusetts, metropolitan area during the years 1975, 1978, 1981 and 1984. The in-hospital and long-term prognoses of 667 patients with AMI complicated by cardiac arrest (CA) was compared with that of 2,596 AMI patients without CA. The incidence of CA complicating AMI was similar (21%) during each of the 4 study years. Among patients with AMI who had CA, 36% had CA within the first day of hospitalization and 48% within the first 2 days. The in-hospital case-fatality rate was much higher for AMI patients with CA (78%) than for those without CA (4%) (p less than 0.001). For patients discharged alive from the hospital, a trend toward a higher mortality rate was seen at 1 and 2 years after hospital discharge for patients with CA; however, long-term survival rates were not significantly different between AMI patients with and without CA. When time of occurrence of CA relative to in-hospital survival was examined, patients with early CA (within 1 day or within 2 days of hospital admission) had a significantly greater in-hospital survival (39% and 34%) than did those with late CA (after 1 day or after 2 days) (13% and 12%). Similarly, patients discharged from the hospital after early CA had a significantly better chance of long-term survival than patients discharged after late CA.