ABSTRACT
<p><b>INTRODUCTION</b>Myocardial infarction (MI) is common and affects a significant number of people annually. Death occurs due to either arrhythmia or heart failure. As leucocytosis, especially elevated neutrophil count, is a hallmark of inflammatory reactions in patients with MI, we investigated the relationship between leucocytosis on admission and left ventricular ejection fraction (LVEF) in patients with acute MI (AMI).</p><p><b>METHODS</b>Patients with AMI were enrolled in a case-control study. Blood samples obtained in the first 24 hours after the onset of pain were analysed for cardiac enzyme levels and cell count. Echocardiography was performed on Days 3-5. Patients with LVEF < 45% were assigned to the left ventricular (LV) systolic dysfunction group (n = 69) and those with LVEF ≥ 45% were taken as controls (n = 69). All patients were matched for variables such as hypertension, diabetes mellitus, hyperlipidaemia, family history of cardiac disease, age and gender.</p><p><b>RESULTS</b>Leucocytosis was higher in patients with systolic dysfunction (47.8%) when compared with the controls (20.3%), and was significantly associated with the development of LV systolic dysfunction (p = 0.001). Similarly, neutrophilia was more common in patients with systolic dysfunction than the controls (6.6% vs. 34.8%), and was significantly associated with LV systolic dysfunction (p < 0.001). Monocytosis was higher in the controls than the systolic dysfunction group (40.6% vs. 33.3%; p = 0.378).</p><p><b>CONCLUSION</b>Leucocytosis and neutrophilia in the acute phase of MI are important predictive factors for the development of LV systolic dysfunction. Leucocytosis can be used for risk stratification of such patients.</p>