The Predictive Value Of Neutrophil To Lymphocyte Ratio And Platelet To Lymphocyte Ratio For In-hospital Major Adverse Cardiovascular Events In Patients With Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention

BackgroundAtherosclerosis is the main pathophysiological process underlying acute cardiovascular diseases. Life-threatening conditions, such as myocardial infarction and ischemic stroke, are provoked by the sudden rupture of vulnerable atherosclerotic plaques, characterized by thin, highly inflamed and collagen-poor fibrous cap. Whereas both innate and adaptive inflammation progressively emerged as driving force of this processes.During the last two decades disclosed that neutrophils play a crucial role in promoting plaque vulnerability by the release of different enzymes, such as gelatinases(matrix metalloproteinases) collagenases, elastase and myeloperoxidase. Accordingly, circulating levels of neutrophils and their products have been investigated as potential markers of plaque instability in both primary and secondary prevention on cardiovascular diseases. When acute myocardial infarction happens,the first leukocytes which infiltrate the infracted myocardium are neutrophils. Moreover, neutrophils are widely recognized as important mediators of myocardial and vascular injury. Due to the fact that the “no-reflow” phenomenon has also been directly linked to neutrophil localization, the neutrophil peak may be related to the reperfusion injury.Evidence from clinical studies revealed that elevation of baseline neutrophil count is associated with higher in-hospital and short-term mortality in patients with AMI,this may be associated with neutrophil localization and the release of different enzymes,so neutrophil is a useful index to predict the incidence of adverse cardiovascular events.Platelet activation plays a crucial role in initiating and propagating thrombosis. Experimental studies have demonstrated that there are increased interactions between platelets and leukocytes in the pathophysiology of AMI. Both leukocytes and platelets adhere to the endothelial lining at the culprit site of coronary artery occlusion. Platelet-neutrophils aggregates may contribute to microvascular plugging and microembolization and mediate the “no-reflow” phenomenon. So the increased number of platelets is associated with adverse clinical outcomes.It has documented a decrease in the total and relative numbers of circulating lymphocytes during AMI and congestive HF.The primary mechanism has been proposed that in response to physiologic stress during myocardial ischemia/infarction. Lymphopenia occurs due to lymphocyte apoptosis and pro-inflammatory cytokines released due to apoptotic cells in acute situation.Neutrophil to lymphocyte ratio and platelet to lymphocyte ratio are new markers incorporating both hematologic indices,they are very useful to predict poor prognosis in patients with acute coronary syndrome. ObjectiveTo investigate the difference and changes of haematological indexes including leukocyte count,neutrophil count,platelet count,lymphocyte count,neutrophil to lymphocyte ratio(NLR) and platelet to lymphocyte ratio(PLR) in patients with acute coronary syndrome before and after percutaneous coronary intervention.To compare the predictive value of NLR and PLR before and after PCI for the in-hospital major adverse cardiovascular events(MACE). MethodsThis was a retrospective study,431 patients with acute coronary syndrome who were hospitalized in cardiovascular department of the first Affiliated Hospital of Zhengzhou University undergoing percutaneous coronary intervention were selected to the study.All the patients were divided into AMI with MACE group(39 cases),AMI without MACE group(156 cases),UAP with MACE group(34 cases)and UAP without MACE group(202 cases) according to clinical diagnosis and whether in-hospital major adverse cardiovascular events(MACE) happened after percutaneous coronary intervention.The clinical data and haematological indexes especially NLR and PLR were made statistically analysis among the four groups.The predictive value of NLR and PLR for the incidence of MACE were explored before and after PCI. Results1. The levels of NLR and PLR were higher in AMI with MACE group and AMI without MACE group than other groups before PCI(P<0.05),The levels of NLR and PLR were higher in AMI with MACE group and UAP with MACE group than other groups after PCI(P<0.05).2. In AMI with MACE group,the level of NLR was higher after PCI compared with that before PCI(P<0.05), the difference of PLR was not statistically significant before and after PCI; In AMI without MACE group,the levels of NLR and PLR were obvious lower after PCI than those before PCI(P<0.05); In UAP with MACE group, the levels of NLR and PLR were obvious higher after PCI than those before PCI(P<0.05);In UAP without MACE group,the levels of NLR and PLR were slightly higher after PCI than those before PCI(P<0.05).3.In multivariate Logistic analysis heart rate on admission, creatinine, age, Gensini score and left ventricular ejection fraction(LVEF)<50% were the risk factors for in-hospital major adverse cardiovascular events after PCI,NLR after PCI(OR3.537,95%CI:2.434-5.140;p=0.000) and PLR after PCI(OR1.013,95%CI:1.008-1.017;p=0.000) were independent predictors for the incidence of MACE.4. Receiver operating characteristic(ROC) curves showed that NLR before PCI,NLR after PCI,PLR before PCI, PLR after PCI with cut-off values of 2.79, 4.89,189.00,182.81 and with area under the curves(AUC)of 0.580(95%CI: 0.506-0.654;P=0.032),0.989(95%CI:0.981-0.996;P=0.000),0.518(95%CI:0.446-0.589;P=0.635),0.740(95%CI:0.673-0.807;P=0.000), respectively, detected the incidence of MACE after PCI in patients with ACS.The sensitivity and specificity of the association between in-hospital MACE and NLR before PCI were74.0% and 45.3%, 98.6% and 91.1% for NLR after PCI,56.2% and53.1% for PLR before PCI,56.2% and 83.2% for PLR after PCI,respectively. ConclusionThe obviously elevated or continuously high level of neutrophil count, combined with the obviously decreased or continuously low level of lymphocyte count after PCI are intimately associated with the adverse clinical outcomes. NLR after PCI is a very useful index to predict in-hospital MACE in Patients with ACS,PLR after PCI has a certain predictive value for in-hospital MACE in patients with ACS.