Risk Stratification and Survival after Myocardial Infarction

TLDR

The study evaluated whether physiologic heart function measurements predict mortality after myocardial infarction. In a multicenter cohort of 866 patients, 24‑hour Holter monitoring and resting radionuclide ejection fraction were performed before discharge. Lower ejection fraction (<0.40) and higher ventricular ectopy (>10 per hour) were independent predictors of mortality, and combinations of four risk factors defined five subgroups with two‑year mortality ranging from 3 % to 60 %.

Abstract

We assessed the role of physiologic measurements of heart function in predicting mortality after myocardial infarction. Most of the 866 patients enrolled in our multicenter study underwent 24-hour Holter monitoring and determination of the resting radionuclide ventricular ejection fraction before discharge. Univariate analyses showed a progressive increase in cardiac mortality during one year as the ejection fraction fell below 0.40 and as the number of ventricular ectopic depolarizations exceeded one per hour. Only four risk factors among eight prespecified variables were independent predictors of mortality: an ejection fraction below 0.40, ventricular ectopy of 10 or more depolarizations per hour, advanced New York Heart Association functional class before infarction, and rales heard in the upper two thirds of the lung fields while the patient was in the coronary-care unit. Various combinations of these four factors identified five risk subgroups with two-year mortality rates ranging from 3 per cent (no factors) to 60 per cent (all four factors).