Sustained benefit 20 years after reperfusion therapy in acute myocardial infarction

The goal of this research was to clarify whether the benefit of reperfusion therapy for myocardial infarction was sustained long-term and to assess the gain in life expectancy by reperfusion therapy.

Reperfusion therapy in acute myocardial infarction reduces infarct size and increases hospital survival.

We analyzed the 20-year outcome of 533 patients (mean age 56 years; 82% men) who were randomized to either reperfusion therapy or conventional therapy during the years 1981 to 1985.

Mean follow-up was 21 years (range 19 to 23 years). At follow-up, 101 patients (36%) of the 269 patients allocated to reperfusion treatment and only 71 patients (26%) of the 264 conventionally treated patients were alive (p = 0.02). The cumulative 10-, 15-, and 20-year survival rates were 69%, 48%, and 37% after reperfusion therapy and 59%, 38%, and 27% in the control group, respectively (p = 0.005). Life expectancy of the reperfusion group was 15.2 years versus 12.4 years in the conventionally treated group (p < 0.0001). Myocardial re-infarction and subsequent coronary interventions were more frequent after reperfusion therapy, particularly during the first year. In multivariable analysis, reperfusion therapy was an important independent predictor of lower mortality at long-term follow-up (hazard ratio 0.7; 95% confidence interval 0.6 to 0.8). Other independent predictors of mortality were age, impaired left ventricular function, multivessel disease, infarct size, and inability to perform an exercise test at the time of discharge.

This is the first study demonstrating sustained (20-year) improved survival after reperfusion therapy. The gain in life expectancy was almost three years, representing about one-third of the life-years lost by myocardial infarction.