The Neutrophil-to-Lymphocyte Ratio Is Valuable at All Stages of Coronary Artery Disease

In their article 'Relationship between neutrophil-to-lymphocyte ratio and left ventricular free wall rupture in acute myocardial infarction', Ipek et al. [1] showed that the neutrophil-to-lymphocyte (N/L) ratio is an independent predictor of left ventricular free wall rupture (LVFWR) in patients with acute myocardial infarction (MI). N/L ratios >3.7 predicted LVFWR with a sensitivity of 82.6% and a specificity of 46.9%. Additionally, in multivariate regression analysis, age, hypertension, increased creatinine levels and an increased N/L ratio were found to be independent predictors of LVFWR. Inflammatory processes play a key role at all stages of coronary artery disease (CAD). This condition activates vascular disease and thrombosis, and results in the dreaded complication of atherosclerosis, which is responsible for MI and most strokes [2]. Neutrophils, which are involved in inflammation, secrete large amounts of several inflammatory mediators. Increased neutrophil counts are independently associated with long-term mortality in patients with MI [3]. On the other hand, a low lymphocyte count reflects a physiological stress response to cortisol and is independently associated with a worse prognosis in patients with CAD [4]. Concordantly, the N/L ratio provides a simple method for the assessment of the inflammatory status and the prognosis of patients with CAD. Recently, the N/L ratio has also been widely used to determine the severity of inflammation in cardiovascular disease [5], diabetes mellitus, hypertension [6] and inflammatory disease [7]. This calculation is very simple and cheap when compared with those involving other inflammatory cytokines. Previous results have demonstrated that adequate collateral circulation has beneficial effects on ventricular function, infarct size and aneurysm formation in MI [8]. In this regard, a meta-analysis of 12 studies showed that patients with adequate coronary collateral circulation have a reduced mortality risk (about 36%) compared with patients with inadequate coronary collateralization [9]. Akın et al. [10] reported that an elevated N/L ratio is independently associated with a significant impairment in coronary collateralization.In conclusion, Ipek et al. [1] reported the N/L ratio as a predictor of rupture of the ventricular wall after MI. In the emergency department, patients with an elevated N/L ratio should be more closely followed up concerning fateful mechanical complications. Finally, in this respect, we strongly believe that the researchers should evaluate the relationship between the N/L ratio and the dreaded mechanical complications in patients with acute MI in large-scale, prospective, randomized clinical trials.