The Value Of Bedside Echocardiography In Evaluating Right Ventricular Function In Patients With V-A ECMO

Objective:To explore the clinical application value of right ventricular parameters related to bedside echocardiography in the changes of right ventricular function in patients with V-A ECMO,and combined with laboratory test indicators,to provide favorable information for clinical evaluation of right ventricular function recovery in patients with V-A ECMO and guidance of ECMO weaning.Methods:A total of 28 patients receiving V-A ECMO support in Intensive Care Unit of the First Affiliated Hospital of Gannan Medical University from January 2021 to December 2022 were selected.According to the outcome of weaning,the enrolled patients were divided into a successful weaning group and a failed weaning group.This study defined weaning failure as death during V-A ECMO support or within 48 hours after V-A ECMO circuit support was removed.Calculated the 30-day survival rate.Echocardiography was collected on the first day of V-A ECMO,the third day of V-A ECMO,the first day before and the first day after weaning from V-A ECMO。Acquiring the parameters:right ventricular internal diameter(RVD),right atrial end-systolic dimension(RADs),right ventricular vertical and vertical diameter,right ventricular basal transverse diameter,tricuspid valve E peak,tricuspid annular plane systolic excursion(TAPSE),right ventricular area change fraction(RVFAC),right ventricular global longitudinal strain(RVGLS).Systolic Sa wave(s’),early diastolic Ea wave(e’),late diastolic Aa wave(a’),E/e’,the interval between the end of Aa wave and the onset of the next Ea wave(a),and the start and end time of s’ wave(b)were measured by tissue doppler imaging on the left side of tricuspid annulus.a-b was the isovolume time,then RVTei index=(a-b)/b.Right ventricular pre-ejection time(PEP),pulmonary artery acceleration time(AT),PEP/AT were calculated.PAMP was estimated according to PAMP=42.1×(PEP/AT)-15.7.And blood biochemical indexes Scr,BUN,arterial blood gas indexes Lac,PO2,PCO2,oxygen saturation and pH were obtained at corresponding time nodes.The changes of right ventricular parameters and test indexes before and after weaning were compared,and the differences of right ventricular parameters and test indexes between the successful weaning group and the failed weaning group at the same time point were compared to find out the right ventricular parameters and test indexes of echocardiography with clinical guiding value.Measurement data to mean+/-standard deviation(X±S)said,S-W method is adopted to improve the normality test.The comparison between the successful weaning group and the failed weaning group showed that the two independent samples t-test was used for the normal distribution,while the Mann-Whitney U test was used for the the abnormal distribution.The paired sample t-test was used for the group with normal distribution,and Wilcoxon signed rank sum test was used for the group with abnormal distribution.Qualitative data were represented by frequency and component ratio,and Fisher’s exact probability method was used to compare the difference of component ratio among groups.Univariate Logistic regression was used to analyze the factors affecting the success of machine removal.The ROC curve of related parameters predicting the success of machineweaning 1 day before offline was drawn to obtain the area under the curve,the prediction cut-off value of each parameter,and the corresponding sensitivity and specificity.P<0.05 was considered as statistically significant difference.Results:1.Among the 28 patients included in this study,there were 21 patients in the successful group and 7 patients in the failed group.The weaning success rate is 75%(21/28).There were 16 males and 12 females.There were no significant differences in age,gender,IABP usage rate,CRRT usage rate,coronary stent history,hypertension history and diabetes history between successful and failed group(P>0.05).The support time of V-AECMO in the successful group(124.76±52.01h)was lower than that in the failed group(218.67±90.31h),and the difference was statistically significant(P<0.05).2.The successful weaning group included 9 patients with low cardiac output syndrome after cardiac surgery,7 patients with acute myocardial infarction induced cardiogenic shock,3 patients with fulminant myocarditis,1 patient with amniotic fluid embolism,and 1 patient with lung contusion;The failure weaning group included 3 patients with low cardiac output syndrome after cardiac surgery,3 patients with acute myocardial infarction induced cardiogenic shock,and 1 patient with fulminant myocarditis.Since there was only one case of amniotic fluid embolism and one case of pulmonary contusion,further Compared with the patients of low cardiac output syndrome after cardiac surgery,acute myocardial infarction induced cardiogenic shock,and fulminant myocarditis showed that the age of patients with low cardiac output syndrome after cardiac surgery(49.00±10.48 years old)was lower than the other two groups.Compared with the acute myocardial infarction induced cardiogenic shock group(61.10±9.76 years old),the difference was statistically significant(P<0.05),and compared with the fulminant myocarditis group(52.25±17.48 years old),the difference was not statistically significant(P>0.05).There were no significant differences in primary disease,gender,CRRT use or IABP use(P>0.05).3.There were no significant differences in right ventricular ultrasonic parameters RVD,RADs,transverse diameter of right ventricular base,upper and lower diameter of right ventricle,TAPSE,peak E of tricuspid valve,s’,e’,a’,E/e’,Tei index,PAMP,RVFAC,RVGLS absolute values,blood biochemical indexes Scr,BUN,arterial blood gas indexes Lac,PO2,PCO2,oxygen saturation and pH in the successful and failed weaning groups(P>0.05).4.The right ventricle TAPSE,s’,RV Tei index,RV FAC,RVGLS absolute values and test indexes Scr and Lac in successful and failed group were significantly different on 3 days and 1 day before weaning(P<0.05).Right ventricular parameters RVD,RADs,transverse diameter of right ventricular base,upper and lower diameter of right ventricle,E peak of tricuspid valve,e′,a′,E/e′,PAMP and test indicators BUN,PO2,PCO2 and pH had no significant changes,with no statistical significance(P>0.05).5.Compared within weaning successful groups,the right ventricular parameters TAPSE,s′,RV FAC and RVGLS absolute values gradually increased on 1 day,3 days,1 day before weaning and 1 day after weaning,while RV Tei index and laboratory test indicators Scr and Lac gradually decreased,with statistical significance(P<0.05);RVD,RADs,transverse diameter of right ventricle base,upper and lower diameter of right ventricle,E peak of tricuspid valve,e′,a′,E/e′,PAMP,BUN,PO2,PCO2 and pH were not significantly changed,with no statistical significance(P>0.05).6.Compared within weaning failure groups,right ventricular parameters RVD,RADs,transverse diameter of right ventricle base,upper and lower diameter of right ventricle,TAPSE,tricuspid peak E,tricuspid ring side s′,e ′,a ′,E/e ′,RVTei index,PAMP,RVFAC,RVGLS absolute values,blood biochemical indexes Scr,BUN,arterial blood gas indexes Lac,PO2,PCO2,oxygen saturation and pH on 1 day,3 days,1 day before weaning,there were no statistical significance(P>0.05).7.Taking death during V-A ECMO support or within 48 hours after V-A ECMO circuit support removal as the criterion ofweaning failure.Univariate logistic regression analysis was performed for TAPSE,s′,RVTei index,RVFAC,RVGLS absolute value,Scr and Lac 1 day before weaning.It was found that TAPSE,RVFAC,RVGLS absolute value and Lac were related to predicting the success of weaning.The ROC curve of predicting the success of weaning 1 day before weaning was plotted.It was found that TAPSE,RVFAC,RVGLS absolute value and Lac had high predictive efficiency,and the absolute value of RVGLS was the most significant.The AUC was 0.915,the diagnostic cut-off value was 6.75%,the specificity was 85.7%,and the sensitivity was 100%.8.Among the 21 patients who received V-A ECMO support treatment and successed weaning,1 died due to active bleeding caused by catheterization site infection and 6 died due to cardiac arrest caused by cardiogenic shock.Therefore,the 30-day survival rate of V-A ECMO patients in this study was 50%(14/28).Conclusion:1.Echocardiographic right ventricular parameters TAPSE,s′,RVTei index,RVFAC and RVGLS are helpful to monitor the changes of patients′ right heart function,and provide clinical data to support the recovery of patients′ heart function after V-A ECMO support.2.Dynamic monitoring of Scr and Lac before weaning of patients undergoing V-A ECMO support therapy is helpful to evaluate the recovery of patients,and Lac level is of certain value in predicting the timing ofweaning.3.By drawing the ROC curve 1 day before weaning,it was found that TAPSE,RVFAC and RVGLS had high diagnostic efficacy in guiding clinical weaning,and the right ventricular parameters for predicting the outcome of weaning were preliminatively obtained,among which RVGLS had the highest diagnostic efficacy and good sensitivity and specificity.