Application Of Echocardiography In Evaluating Right Ventricular Structures And Functions In Patients With CTEPH After Balloon Pulmonary Angioplasty

BackgroundChronic thromboembolic pulmonary hypertension(CTEPH)is a progressive pulmonary vascular disease,which is a group of syndromes characterized by dyspnea,fatigue,and decreased activity tolerance.Pulmonary endarterectomy(PEA)can improve the symptoms and prognosis of CTEPH patients with proximal pulmonary vascular lesions,and is currently the preferred treatment for CTEPH.Balloon pulmonary angioplasty(BPA)is an emerging and effective treatment for CTEPH patients with distal vasculopathy or those who cannot tolerate PEA surgery.Patients with CTEPH often require multiple BPA procedures to effectively improve their symptoms and reduce pulmonary artery pressure.Then the postoperative effect of BPA in patients with different degrees of CTEPH are not the same,and the short-term postoperative effects are closely related to the long-term prognosis.Therefore,shortterm follow-up after BPA in CTEPH patients is particularly important,and evaluating the immediate effect of on pulmonary hemodynamics,right ventricular(RV)structure and function in CTEPH patients is also important for the formulation of subsequent treatment plans.ObjectiveThe purpose of this study was to investigate the value of echocardiography in evaluating the structural,functional and hemodynamic changes of the right heart in the short term after BPA in patients with CTEPH.MethodsIn this prospective study,30 CTEPH patients undergoing BPA procedure underwent right heart catheterization(RHC)before and after balloon dilation to assess hemodynamic parameters,including right atrial pressure(RAP),pulmonary artery systolic pressure(PASP),pulmonary artery diastolic pressure(PADP),pulmonary capillary wedge pressure(PCWP),pulmonary vascular resistance(PVR)and cardiac output(CO).Echocardiography was performed within 1 week before BPA and within 24 hours after BPA.Detect the cardiac structural parameters of patients on echocardiography,including main pulmonary artery diameter(DMPA),right ventricular basal segment diameter(RVD1),right ventricular anteroposterior diameter(RVD2),right atrial long diameter(RAD1),right atrial transverse diameter(RAD2),Left ventricular end-diastolic diameter(LVDd),right ventricular end-diastolic area(RVEDA),right ventricular end-systolic area(RVESA),right atrial end-diastolic area(RAEDA),right atrial end-systolic area(RAESA),pulmonary artery systolic pressure(PASP)).Echocardiographic cardiac function parameters of patients were detected,including peak tricuspid annular systolic velocity(S’),tricuspid annular plane systolic displacement(TAPSE),right ventricular myocardial work index(RIMP),and right ventricular area change fraction(RVFAC),left ventricular stroke volume(LVSV).The RHC parameters,echocardiographic cardiac structural and function parameters were compared between before and after BPA patients.ResultsPASP measured noninvasively through echocardiography was significantly correlated with PASP obtained invasively from RHC in 30 patients with inoperable CTEPH.RHC parameters including pulmonary artery systolic pressure(PASP),pulmonary artery diastolic pressure(PADP),mean pulmonary artery pressure(mPAP),and pulmonary vascular resistance(PVR),and echocardiography structural parameters including right atrium diameter(RAD1),transverse right atrial diameter(RAD2),right ventricular end-diastolic area(RVEDA),right ventricular end-systolic area(RVESA),right atrium end-diastolic area(RAEDA),right atrium end-systolic area(RAESA)and left ventricular end diastolic diameter(LVDd)had been significantly improved within 24h after BPA(p<0.05).However,there were no significant differences in echocardiography function parameters including tissue Doppler-derived tricuspid lateral annular systolic velocity(S’),tricuspid annular plane systolic excursion(TAPSE),right ventricular index of myocardial performance(RIMP),right ventricular fractional area change(RVFAC)and left ventricular stroke volume(LVSV).ConclusionsBPA can significantly reduce the pulmonary artery pressure,improve the right ventricular volume load,and reduce the compression of the right ventricle to the left ventricle in CTEPH patients.The resulting improvement in cardiac structure and pulmonary artery pressure can be effectively and non-invasively monitored by echocardiography.Compared with preoperative,the inner diameter of main pulmonary artery,right ventricle and right atrium decreased,left ventricular end-diastolic diameter increased,and pulmonary arterial pressure decreased within 24 hours after BPA.However,the improvement of right ventricular systolic function is not obvious for the time being,and further research is needed in the middle and long-term after operation.PASP estimated by echocardiography was significantly correlated with PASP measured by right heart catheterization,it shows that echocardiography can monitor PASP noninvasively and continuously.