QRS duration as a predictor of low ejection fraction in the ST segment elevation myocardial infarction

Introduction: The QRS duration is a prognostic element and it has been assodated with a decrease in the left ventricular ejection fraction in patients with acute coronary syndrome. Obecilve: To assess the prognostic implications of the QRS duration in the depression of the left ventricular ejection fraction at discharge. Method: A cross-sectional study was conducted with 347 patients with ST-segment elevation myocardial infarction, admitted at the Hospital Universitario Camilo Cienfuegos from January Is, 2013 to December 31st, 2015. The variables studied were: age, sex, classical cardiovascular risk factors, blood pressure, reperfusion strategy, Killip-Kimball class, glomerular filtration rate, QRS duration and left ventricular ejection fraction. The qualitative variables were analyzed with the Chi-square statistical method and the quantitative with the t of Student and linear regression. The ROC curve was constructed for the discrimination capacity and a multivariate analysis was performed to determine the independence of variables. Results: The QRS duration was negatively correlated with the ejection fraction 0.267; p<0.001) and an adequate discrimination ability as a predictor ejection fraction less than 35% (c=0.643). Conclusions: The QRS duration greater than 90 milliseconds was independently associated with an ejection fraction lower than 35% at discharge.