The Relationship Between RDW And Severity Of Coronary Artery Lesions And Cardiac Function In Patients With Acute Coronary Syndrome

Background and ObjectiveAcute coronary syndrome(ACS)is a series of clinical syndromes caused by acute myocardial ischemia,which is due to coronary spasm or thrombosis caused by activation of platelets by rupture of coronary atherosclerotic plaques,with rapid disease development and high mortality.Early assessment of the severity of coronary artery lesions and cardiac function as well as timely treatment in ACS patients are essential to improve their prognosis.Coronary angiography is the “golden standard” for judging coronary artery lesions,but the examination is invasive and requires high level of doctors as well as equipments,so that some hospitals can not carry out it.Cardiac color Doppler echocardiography is an objective standard for evaluating cardiac function,but it is less sensitive to identify early cardiac insufficiency.Therefore,reliable biomarkers are necessary supplements for evaluating the severity of coronary artery lesions and cardiac function.Previous studies have found that Red blood cell volume distribution width(RDW)has the effect of inflammatory factors and is associated with cardiovascular diseases such as ACS and heart failure,its application value in cardiovascular field has attracted much attention.It is not clear whether RDW is of clinical value in assessing the severity of coronary artery lesions and cardiac insufficiency in patients with ACS.This study retrospectively analyzed the relationship between RDW and severity of coronary artery lesions as well as cardiac function in ACS patients,in order to explore the clinical value of RDW in assessing severe coronary artery lesions and cardiac insufficiency in ACS patients.Materials and MethodsThe retrospective analysis was made of 500 patients with ACS who underwent coronary angiography in the Second Affiliated Hospital of Zhengzhou University from January 2017 to December 2017.According to the quartile method,all patients were divided into four groups according to the level of RDW: Q1 group(RDW?12.3%),Q2 group(12.3% < RDW?12.8%),Q3 group(12.8% < RDW?13.4%)and Q4 group(RDW > 13.4%).The general data,the results of laboratory test and color Doppler echocardiography within 24 hours of admission were collected.Gensini scores were calculated according to the results of coronary angiography.SPSS22.0 software was used for statistical analysis.The clinical data of patients with different RDW levels were compared.Logistic regression was used to analyze the relationship between RDW and severe coronary artery lesions as well as cardiac insufficiency.The diagnostic value of RDW for severe coronary artery lesions and left ventricular systolic dysfunction was evaluated by ROC curve.Test level: a = 0.05,P < 0.05 has statistical significance.Results1.Comparison of general clinical data among the four groups: There were no significant differences in smoking,hypertension,diabetes,glycosylated hemoglobin(HbA1c),white blood cell(WBC),creatinine(Cr),cholesterol(TC),high density lipoprotein(HDL-C),low density lipoprotein(LDL-C)among the four groups(P > 0.05).Compared with the other three groups,Q4 group had higher age,higher male proportion,lower Hb level,higher natural logarithm of high-sensitivity C-reactive protein(lnhsCRP),creatine kinase-MB(CK-MB),natural logarithm of Troponin-T(lncTnT)and triglyceride(TG)levels,and there were significant differences between the four groups(P < 0.05).2.RDW and coronary artery lesions: Patients in Q4 group had more coronary artery lesions and higher Gensini score.There were significant differences between the two groups(P < 0.05).RDW was positively correlated with the number of lesion branches(r = 0.305,P < 0.05).There was significant difference in Gensini score between the four groups(P < 0.05).Univariate logistic regression analysis showed that hypertension,RDW,CK-MB,cardiac troponin-T(cTn-T),left ventricular ejection fraction(LVEF)were the factors that affecting the severity of coronary artery lesions(Gensini > 60 points).The above factors were included in multivariate logistic regression analysis,and the variables were selected by likelihood ratio advance method.The selected variables were RDW(OR= 1.183,95% CI 1.008-1.389,P < 0.05),cTn-T.(OR = 1.098,95% CI 1.011-1.193,P < 0.05),CK-MB(OR = 1.504,95% CI 1.094-2.067,P < 0.05).3.RDW and cardiac function: There were no significant differences in left ventricular end diastolic dimension(LVDd),early left ventricular diastolic maximum flow/mitral atrial systolic maximum flow(E/A),and natural logarithm of N-terminal pro-brain natriuretic peptide(LnNT-proBNP)among the four groups(P > 0.05).The LVEF of Q4 group was significantly lower than that of other groups,and there was significant difference between the two groups(P < 0.05).RDW was negatively correlated with LVEF(r = 0.240,P < 0.05).Univariate logistic regression analysis showed that RDW,CK-MB,cTn-T,NT-proBNP and Gensini > 60 were the factors affecting left ventricular systolic dysfunction(LVEF < 50%).The above indexes were included in multivariate logistic regression analysis,and the variables were selected by likelihood ratio advance method.The selected variables were RDW(OR= 1.270,95% CI 1.073-1.505,P < 0.05),NT-proBNP(OR= 1.151,95% CI 1.006-1.318,P < 0.05).4.Diagnostic efficacy of RDW: When RDW was 12.85%,its predictive value for severe coronary artery lesions was the highest,with sensitivity 60.7%,specificity 62.9%,area under ROC curve(AUC)62.6%(95% CI: 0.576-0.676);when RDW was 12.75%,its predictive value for left ventricular systolic dysfunction was the highest,sensitivity 65.4%,specificity 53.8%,AUC 61.1%(95% CI: 0.559-0.663).conclusion1.RDW was positively correlated with the severity of coronary artery leison.The higher the level of RDW,the more severity degree of the coronary artery lesions.2.RDW was negatively correlated with LVEF.The higher the level of RDW,the worse the left ventricular systolic function.3.RDW has certain clinical value in predicting severe coronary artery lesions and left ventricular systolic insufficiency.Its truncation value are 12.85% and 12.75%.