Assessment of immediate prognosis in acute myocardial infarction by a new noninvasive hemodynamic index.

A prognostic index for acute myocardial infarction was developed from noninvasively accessible parameters, gathered prospectively within 24 h from the onset of symptoms in 185 consecutive patients. Of the 35 patients who died in hospital, 30 had power failure. The items subjected to discriminant function analysis were: sex, age, number of previous infarctions, present infarction transor nontransmural, heart rate, systolic arterial pressure (SAP), left ventricular ejection time (LVET), cardiothoracic ratio, and grade of pulmonary venous congestion scored 0-3 (PVC0-3). The items possessing the best predictive power were, in the order of their strength: age, SAP, LVET and PVCO-3; i.e., hemodynamically, afterload, stroke volume and preload. The discriminant function (DF) giving the prognostic score was: DF=3.9Xage(yr)-1.3X SAP (mm Hg) - 1.4 X LVET (msec) + 25.3 X PVC0-3 + 775.3 Score 550 was exceeded by 87% of the patients dying of power failure and only 16% of the survivors, and it was less in 84% of the survivors and 13% of those dying. To test the validity of the index it was applied to another series consisting of 100 consecutive patients and very similar results were obtained, suggesting that the index is of practical value in predicting hemodynamic deterioration early and by simple noninvasive means.