The Value Of Echocardiography In Evaluating The Complexity Of Coronary Artery Lesion And Predicting Outcome In Patients Undergoing Coronary Artery Bypass Grafting

Objective:Cardiovascular disease remains the highest incidence and mortality rate in the world.Coronary artery disease(CAD)is the most common cardiovascular disease,and coronary artery bypass grafting(CABG)has been an effective treatment of complex and severe CAD.It is of great clinical significance to accurately non-invasive evaluate the complexity of CAD and the prognosis of CABG.The SYNTAX score which can reflect the complexity and severity of coronary lesions is usually calculated during coronary angiography,however,it is obtained through an invasive method which may be limited by frequently repeated checks.In addition,the latest guideline for myocardial revascularization recommend the use of STS score(I B)and EuroSCORE II(IIb B)to evaluate the occurrence of perioperative outcome,while there are currently no recommended scores or parameters to evaluate long-term outcome in patients following CABG.Therefore,Clinical method which could non-invasively reflect the complexity of coronary lesions and could predict perioperative and long-term outcome following CABG is needed.Echocardiography is an optimum method for the preoperative diagnosis and evaluation of postoperative efficacy in patients undergoing CABG.However,it is not clear whether the echocardiographic parameters can accurately reflect the complexity of coronary artery lesions.Besides,the prognostic value of the echocardiographic parameters in patients following CABG remains unknown.Therefore,this study sought to comprehensively investigate the role of echocardiography in non-invasive detecting the complexity of coronary artery lesion and predicting perioperative and long-term outcome in patients following CABG,so as to provide comprehensive information for clinical diagnosis,treatment and prognosis.Methods:Consecutive patients who underwent isolated CABG in our hospital between September 2016 and June 2019 were included in this study.Patients were excluded if they had a combination of valvular disease,cardiomyopathy disease,congenital heart disease,macrovascular disease,atrial fibrillation and other malignant arrhythmias,temporary and permanent implanted pacemaker,severe liver and kidney dysfunction,and previous history of open-heart surgery.All patients underwent coronary angiography before CABG and the SYNTAX score was calculated.The baseline clinical characteristics such as the patient’s age,gender,blood pressure,blood glucose and conventional blood biochemical markers were collected.A baseline comprehensively transthoracic echocardiography was performed for each patient 3 days before CABG.Echocardiographic parameters were measured as follows:Left ventricular systolic function parameters including left ventricular end-diastolic(LVEDV)and end-systolic volume(LVESV),left ventricular ejection fraction(LVEF)and left ventricular global longitudinal strain(LVGLS);left ventricular diastolic function parameters including transmitral peak E-wave velocity(E),e velocity of septal(Septal-e’)and lateral(Lateral-e’)annulus by pulsed wave tissue Doppler imaging,left atrial volume index(LAVI)and tricuspid regurgitation velocity(TRV);right ventricular systolic function parameters including right ventricular fractional area change(RVFAC),tricuspid annular plane systolic excursion(TAPSE).Then the patients’information was entered into the web calculator to calculate the STS score and Euro SCORE II.All patients were followed up after CABG to determine if any perioperative and long-term outcomes occurred.Long-term follow-up was conducted mainly through outpatient revisits,medical records of readmission and telephone follow-up every 6months.Perioperative outcome was defined as a composite event of major morbidity and mortality,including death,stroke,acute renal failure requiring dialysis,prolonged ventilation,deep sternal wound infection and reoperation for any reason.The long-term outcome was defined as major adverse cardiovascular and cerebrovascular events(MACCE)occurred from the time of cardiac surgery to the end of follow-up,including all-cause death,recurrent myocardial infarction,revascularization,stroke,and renal failure requiring dialysis.Logistic regression analysis was used to determine the relationship between each parameter and the high SYNTAX score(≥33),and receiver operating characteristic curve(ROC)was used to determine the diagnostic performance of each parameter on the high SYNTAX score.Logistic regression analysis was used to determine the independent predictors of perioperative outcome.Cox proportional hazards regression analysis was used to determine the independent predictors of long-term MACCE and long-term death.The predictive power of each model was evaluated by comparing the chi-squared values obtained by the likelihood ratio test.Kaplan-Meier curve log rank test was used to compare the incidence of perioperative adverse event and long-term event-free survival.A P-value less than 0.05 was considered to be statistically significant.Results:1、Relationship between preoperative echocardiography parameters and high SYNTAX score in patients undergoing CABGA total of 117 patients were enrolled(61.2±8.2 years,85.5%males).The average SYNTAX score was 32.76±9.35.According to the SYNTAX score,the patients were divided into the intermediate and low SYNTAX score group(<33,no.58)and the high SYNTAX score group(≥33,no.59).LVEF,Septal-e’,and LVGLS reduced significantly in the high SYNTAX group(P<0.05).Septal-e’and neutrophil(NE)were the independent predictors of high SYNTAX score.By ROC analysis,Septal-e’less than4.35 cm/s had a sensitivity of 59.3%and a specificity of 69.0%for the identification of high SYNTAX score(AUC=0.66,P<0.01).A combination of Septal-e’and NE had a sensitivity of 88.1%and a specificity of 53.5%for the identification of high SYNTAX score(AUC=0.70,P<0.001).Compared with NE(AUC=0.59,P=0.09).,the diagnostic performance has significantly improved by combining Septal-e’and NE for the identification of high SYNTAX score(P<0.05).2、The predictive value of echocardiographic parameters for perioperative outcome in patients following CABG 24(20.51%)patients occurred perioperative outcome,including 3 deaths,1 strokes,2acute renal failures,22 prolonged ventilation and 1 deep sternal wound infections.EuroSCORE II could predict perioperative outcome(P<0.01),while the STS score could not predict perioperative outcome(P>0.05).LVGLS and RVFAC were independent predictors of perioperative outcome.LVGLS and RVFAC could provide the incremental value of EuroSCORE II for predicting perioperative outcome following CABG.A model based on EuroSCORE II(χ~2=12.81)was significantly improved by addition of LVGLS and RVFAC(χ~2=23.69,P<0.001)to predict perioperative outcome in patients following CABG.The quartiles of baseline LVGLS and RVFAC predicting perioperative outcome were-11.50%and 41.39%.The patients with LVGLS≥-11.50%had a significantly higher incidence of perioperative adverse event than those with LVGLS<-11.50%(P<0.001);the patients with RVFAC<41.39%had a significantly higher incidence of perioperative adverse event than those with RVFAC≥41.39%(P<0.001).3、The predictive value of echocardiographic parameters for long-term outcome in patients following CABGAt a median follow-up of 2.06 years,follow-up data were available for 115(98.29%)of the patients.Long-term MACCE occurred in 24(20.87%)patients,including 12deaths,9 strokes,5 recurrent myocardial infarction,3 repeat coronary revascularizations,and 2 renal failures.STS score and EuroSCORE II could predict long-term MACCE(P<0.05).LVGLS,LAVI and left ventricular diastolic dysfunction(LVDD)were independent predictors of long-term MACCE.LVGLS,LAVI and LVDD could provide the incremental value of STS score and EuroSCORE II for predicting long-term MACCE following CABG.A model based on STS score(χ~2=10.12)was significantly improved by addition of LVGLS LAVI and LVDD(χ~2=43.75,P<0.001)to predict long-term MACCE in patients following CABG.A model based on EuroSCORE II(χ~2=6.71)was significantly improved by addition of LVGLS LAVI and LVDD(χ~2=39.36,P<0.001)to predict long-term MACCE in patients following CABG.Furthermore,STS score combined with the echocardiography parameters has a better predictive performance for predicting long-term MACCE compared with Euro SCOREⅡcombined with echocardiography parameters(χ~2=43.75,vs.χ~2=39.36,P<0.001).The quartiles of baseline LVGLS and LAVI predicting long-term MACCE were-11.37%and 34.92m L/m~2.Kaplan-Meier curve analysis showed that the patients with LVGLS<-11.37%had a significantly higher incidence of long-term event-free survival than those with LVGLS≥-11.37%(P<0.05);the patients with LAVI<34.92mL/m~2 had a significantly higher incidence of long-term event-free survival than those with LAVI≥34.92m L/m~2(P<0.001);patients without LVDD had a significantly higher incidence of long-term event-free survival than those with LVDD(P<0.05).STS score and EuroSCORE II could predict long-term death(P<0.05).NYHA functional classification and LAVI were independent predictors of long-term death(P<0.05).NYHA functional classification and LAVI could provide the incremental value of STS score and Euro SCORE II for predicting long-term death following CABG.A model based on STS score(χ~2=12.43)was significantly improved by addition of NYHA functional classification and LAVI(χ~2=30.38,P=0.001)to predict long-term death in patients following CABG.A model based on EuroSCORE II(χ~2=7.22)was significantly improved by addition of NYHA functional classification and LAVI(χ~2=26.76,P=0.001)to predict long-term death in patients following CABG.Furthermore,STS score combined with NYHA functional classification and LAVI has a better predictive performance for predicting long-term death compared with EuroSCOREⅡcombined with NYHA functional classification and LAVI(χ~2=30.38,vs.χ~2=26.76,P<0.001).Kaplan-Meier curve analysis showed that the patients with NYHA functional classification gradeⅠand NYHA functional classification gradeⅡhad a significantly higher long-term survival rate than those with NYHA functional classification gradeⅢand NYHA functional classification gradeⅣ(P<0.05),and the patients with LAVI<34.92mL/m~2 had a significantly higher long-term survival rate than those with LAVI≥34.92m L/m~2(P=0.001).Conclusions:1、Preoperative Septal-e’and NE were independent predictors of high SYNTAX score (≥33)in patients undergoing CABG,and the combination of Septal-e’and NE significantly improved diagnostic performance for identifying high SYNTAX score.2、EuroSCORE II could predict perioperative outcome.LVGLS and RVFAC were independent predictors of perioperative outcome.A combination of LVGLS and RVFAC could provide the incremental value to the EuroSCORE II for predicting perioperative outcome in patients following CABG.3、STS score and EuroSCORE II could predict long-term MACCE.LVGLS,LAVI and LVDD were independent predictors of long-term MACCE.LVGLS,LAVI and LVDD could provide the incremental value of STS score and EuroSCORE II for predicting long-term MACCE following CABG.Furthermore,STS score combined with echocardiography parameters had a better predictive performance for predicting long-term MACCE.4、STS score and EuroSCORE II could predict long-term death,NYHA functional classification and LAVI were independent predictors of long-term death,and NYHA functional classification and LAVI could provide the incremental value of STS score and EuroSCORE II for predicting long-term death following CABG.Furthermore, STS score combined with NYHA functional classification and LAVI had a better predictive performance for predicting long-term death.