Predictive Value of Lymphocyte Based Indices to Determine Major Adverse Cardiovascular Events in Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention

Acute coronary syndrome (ACS) is leading cause of mortality worldwide. Percutaneous coronary intervention (PCI) is the main stay of treatment in patients presenting with ACS. However, studies have shown that PCI itself may induce and promote inflammatory process. Lymphocyte based hematological indices: neutrophil lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), monocyte lymphocyte ratio (MLR) and systemic inflammatory index (SII) have been shown as effective indicator of underlying inflammatory process. We conducted a prospective observational follow up study to observe the changes in NLR, PLR, MLR and SII before and after PCI in ACS patients and their predictive value in determining major adverse cardiac events (MACE) and prognosis in these patients. Blood samples were collected from 403 ACS patients at admission and within 48 h of PCI. NLR, PLR, MLR and SII decreased from baseline which was suggestive of resolving inflammation following PCI. ROC curve analysis showed post PCI SII has highest predictive value for incidence of MACE. Cox multivariate analysis showed post-PCI hematological indices were predictors of MACE including all-cause mortality. Patients with elevated inflammatory indices had poor survival outcomes compared to those having low values. Thus, it could be concluded that compared to pre-PCI inflammatory markers, post-PCI inflammatory markers showed stronger correlation in predicting MACE. Among post PCI indices, SII had the strongest correlation with incidence of MACE during the follow up.