White Blood Cell/Mean Platelet Volume Ratio as a Predictor of Long-Term Outcomes but Not Coronary Artery Disease Severity in Non-ST Elevation Myocardial Infarction Patients

Background White blood cell count (WBC) and mean platelet volume (MPV) have been shown to be hematologic parameters of prognostic significance in acute coronary syndrome. We sought to determine the relationship between the WBC/MPV ratio (WMR), coronary artery disease (CAD) complexity, and long-term clinical outcomes in patients with non-ST elevation myocardial infarction (NSTEMI). Hypothesis WMR has a relationship with the complexity of CAD and long-term clinical outcomes in NSTEMI patients. Methods A total of 289 NSTEMI patients who underwent coronary angiography were divided into two groups according to the median WMR (>970 or ≤970). CAD complexity was assessed with the SYNTAX score. Results The WMR was not associated with the synergy between percutaneous coronary intervention (PCI) with Taxus and cardiac surgery (SYNTAX) score on multivariate linear regression analysis (ß=0.08, 95% CI = -0.76-2.21, p = 0.14). However, it was of prognostic significance on Kaplan-Meier survival analysis in overall patients (log-rank p = 0.03) and in patients with a SYNTAX Score <22 (log-rank p = 0.01). Follow-up data showed that major adverse cardiac events (MACE) (p = 0.02), death (p < 0.001), non-fatal MI (p = 0.03), ischemia-driven revascularization (p = 0.03), and heart failure (p = 0.04) were more frequent in the high WMR group. After adjustment for age, sex, eGFR, troponin levels, and the Global Registry of Acute Coronary Events (GRACE) score in Cox regression models, the association of high WMR with the cumulative incidence of MACE was preserved (overall patients (HR=1.85, 95% CI 1.1-3.12, p=0.02) and patients with a SYNTAX score <22 (HR=2.06, 95% CI 1.15-3.67, p=0.01). Conclusion The WMR was not related to CAD complexity, but it was associated with long-term clinical outcomes in patients with NSTEMI who underwent coronary angiography.