The initial chest X-ray in acute myocardial infarction. Prediction of early and late mortality and survival

Abstract

To evaluate the importance of the initial chest x-ray in predicting mortality and survival after acute myocardial infarction, the degree of pulmonary congestion, cardiothoracic ratio and left-heart dimension on the initial chest x-ray obtained from 273 patients within 24 hours of admission after acute myocardial infarction were related to early (30 days) and late (6 months, 1 yr) mortality. The chest films were divided into four degrees of pulmonary venous congestion: grade 0 - no pulmonary congestion (n = 141); grade 1 - redistribution of pulmonary blood flow (n = 38); grade II - interstitial pulmonary edema (n = 61); grade III - localized alveolar edema (n = 20); grade IV - diffuse alveolar edema (n = 13). In the absence of pulmonary congestion, 94% of the patients survived the first months and 88% of them survived 1 year; when the heart size was also normal, more than 96% of patients survived 1 month and more than 91% survived 1 year. The 30-day mortality was significantly (p < 0.005) higher with grades II, III, and IV pulmonary venous congestion than with grade 0, and late mortalities increased significantly (p < 0.005) with any degree of pulmonary venous congestion compared with grade 0. Mortalities with grades II and III congestion were similar, and less than 50% of the patients were alive after 1 year. With grade IV, only 18% of patients survived after 30 days and none after 1 year. Without pulmonary venous congestion, 24% of patients with increased initial left-heart dimension (≥ 50 mm/m2) and increased cardiothoracic ratio (≥ 0.05) died during the subsequent year, compared with only 6% of patients with normal initial cardiothoracic ratio. Early and late mortality in patients without pulmonary venous congestion was significantly lower (p < 0.01) than in patients with any degree of pulmonary venous congestion, regardless of left-heart dimension or cardiothoracic ratio. Thus, the degree of congestion and left-heart size on the initial chest x-ray after acute myocardial infarction are highly useful for defining groups with increased risk of dying or surviving within the first month or the first year after the acute event.