5993 Survivors of suspected myocardial infarction - 10 year incidence of later myocardial infarction and subsequent mortality

Aims To evaluate the 10-year incidence of later infarction and subsequent mortality, as well as predictors of later infarction, in patients with suspected myocardial infarction and alive on day 15 after admission. Methods and Results 5993 patients admitted with suspected myocardial infarction and alive on day 15 after admission were registered in The First Danish Verapamil Infarction Trial database in 1979-81. 2586 had definite infarction, 402 probable infarction and 3005 no infarction as they fulfilled 3, 2 and 1 criteria for infarction. They were followed for 10 years with respect to later infarction and death: i.e. including death after later infarction. The 10 year infarction rate after index admission was 48.8% in definite, 47.3% in probable and 24.6% in no infarction patients (P<0.0001). The subsequent 10-year mortality was 82.3% in primary definite, 74.7% in primary probable, and 77.9% in primary no infarction patients (ns). Cox regression analysis with sex, age group, and definite, probable or no infarction as independent variables showed that females aged <50 years without a primary infarction had the lowest hazard ratio (0.13 relative to males, aged 50-65 years with definite/probable infarction at index admission) for a later infarction, in contrast to the highest hazard ratio (1.17) for males aged >65 years with definite or probable infarction. Conclusion The 10-year infarction rate in patients with suspected myocardial infarction in whom the diagnosis is ruled out is lower than in those with definite or probable infarction, but the mortality after a later infarction is similar in all three groups.