The prognostic value of total neutrophil count, neutrophil/lymphocyte ratio and left ventricular ejection fraction in predicting in- hospital mortality and complications after acute STEMI

Abstract

Background: Leukocytosis, predominantly neutrophilia has previously been described following ST elevation myocardial infarction (STEMI). The exact contribution of this phenomenon to the clinical outcome of STEMI is yet to be shown. We examined cellular inflammatory response to STEMI in the blood by assessing total neutrophil count (TNC), neutrophil to lymphocyte ratio (NLR) and Left ventricular ejection fraction (LVEF) post myocardial infarction and their association with inhospital mortality and/or adverse clinical events. Methods: In this cross-sectional study, 50 patients who were admitted with the diagnosis of acute STEMI at Government medical college and Hospital, Amritsar were studied. The complete blood cell count (CBC) was done in all patients within12-24 hours of the onset of symptoms. Total leukocyte count and differential leukocyte count were performed and neutrophil/lymphocyte ratio (NLR) was calculated. Left ventricular ejection fraction was assessed within one week of MI. Association of cellular response and ejection fraction with the incidence of post-MI mortality/complications like pulmonary edema, cardiogenic shock, arrhythmias and blocks were assessed by using ROC curve analysis and chi square test. Results: In-hospital mortality and post-STEMI complication rate were 8% and 42%, respectively. Total neutrophil count (P=0.029) and Neutrophil to lymphocyte ratio (P=0.001) were predictors of mortality. High NLR (P<0.001) and lower LVEF (P<0.001) were predictors of total complications and cardiogenic shock. Pump failure in the form of acute pulmonary edema (6%) or cardiogenic shock (8%) occurred in 7 (14%) patients. Higher total neutrophil counts (P=0.009), higher NLR (P<0.001) and lower ejection fraction (P<0.001) were predictors of pulmonary edema. The frequency of ventricular tachyarrhythmias (VT/VF) at the first day was associated with higher NLR level (P=0.029).High TNC and low LVEF were predictors for first degree heart block and high NLR was predictor for third degree heart bock and left bundle branch block. Conclusion: A single CBC analysis along with routinely assessed parameter i.e. ejection fraction may help to identify STEMI patients at risk for mortality and heart failure, while neutrophil to lymphocyte ratio is the most valuable in predicting both.