Reappraisal of the Norris score and the prognostic value of left ventricular ejection fraction measurement for in-hospital mortality after acute myocardial infarction.

A retrospective analysis of all patients admitted to an academic suburban hospital with a diagnosis of acute myocardial infarction was performed to evaluate the usefulness of the addition of left ventricular ejection fraction to the Norris score in predicting in-hospital mortality. Although both the Norris score and ejection fraction predicted mortality in univariate analysis, multivariate logistic regression analysis revealed only 3 independent variables: ejection fraction, age, and admission systolic blood pressure, which are incorporated to form a new simplified scoring system.