The Role Of Pulmonary Valve Pressure Gradient In Estimating Pulmonary Artery Systolic Pressuress In Patients With Atrial Septal Defect

Background and Objective: Atrial septal defect(ASD)is one of the most common congenital heart disease.Long-term left to right shunt in ASD leads to the development of right heart volume overload and secondary pulmonary hypertension(PH),elevated of pulmonary artery pressure eventually leads to right heart failure or even death and reduce the quality of patient's life.Right-heart catheterization(RHC)remains the criterion standard for the diagnose of PH per PAH guideline.However,RHC is an invasive procedure and always not practical for repeated ongoing evaluation.Several investigators have demonstrated an adequate correlation between the Doppler estimates and direct measurements with RHC of pulmonary artery systolic pressure(PASP).Ultrasound echocardiography(UCG)is always applied to clinical practice because of its non-invasive?feasible and relatively cheap.UCG is recommended as the initial noninvasive modality in the screening and evaluation of PAH.However,the accuracy of pulmonary artery pressures by UCG has been called into question in recent years.In some clinical settings,there are different degrees of underestimation or overestimation of PASP measured by the method of of the tricuspid regurgitation jet in quite a few patients.Some clinical trials have discussed the impact of estimation of right ventricular systolic pressure and right atrial pressure,the degree of TR,the angle of TR recurrent by UCG continuous Doppler measurement,and difference of cardiac catheterization exam time on UCG assessment of PASP.But whether the influence of size of ASD and pulmonary valve pressure gradient in assessment of pulmonary artery pressure by UCG is not clear.The study was aimed to evaluate the accuracy of estimated pulmonary artery systolic pressure by echocardiography and discuss the role of cross-pulmonary valve pressure(PVPG)to calculate of pulmonary artery systolic pressure in patients with atrial septal defect(ASD),and compare the differences between PASP of postoperative and preoperative.Methods: 1.68 patients with ASD were used tricuspid regurgitation pressure gradient method for pulmonary artery systolic pressure(PASP)were measured before interventional occlusion operation.And pulmonary valve pressure gradient were measured through pulmonary valve velocity to calculate PASP'.2.The patients were divided into group A(defect size?15mm)and group B(defect size>15mm).Compared the mearsurements PASP and PASP' obtained by UCG with PASPr obtained by RHC between the two groups respectively.3.Follow-up the patients who were underwent ASD chosure after three months,compare the differences between PASP of postoperative and preoperative.Results : 1.Sixty eight patients with ASD were used tricuspid regurgitation pressure gradient method for meassuring pulmonary artery systolic pressure(PASP)before interventional occlusion operation in Tianjin Medical University General Hospital.And pulmonary valve pressure gradient were measured through pulmonary valve velocity to calculate corrected values(PASP').They were compared with those(PASPr)obtained by RHC respectively.The patients were divided into group A(defect size?15 mm)and group B(defect size>15 mm)by the size of defect.Compared the mearsurements obtained by UCG and RHC between the two groups.Results There were no statistically significant difference between PASP [(31.66±6.76)mm Hg],PASP' [(26.86±6.66)mm Hg] and PASPr [(28.79±6.43)mm Hg](P>0.05)of group A;The PASP is higher than PASPr[(45.29±13.49)mm Hg vs(34.56±9.47)mm Hg,P<0.05],there were no statistically significant difference between PASP' [(37.30±12.71)mm Hg] and PASPr(P>0.05)of group B.The PASPs were positive correlated with PAPSr(respectively r =0.664,0.588,P<0.01).The correlation coefficients were improved between PASPr and PASP' in group A and B after adjusted with pulmonary valve pressure gradient(respectively r =0.700,0.645,P<0.01).Accoridng to Bland-Altman's analysis,the bias between the PAPSr and PASP in group B averged-10.7 mm Hg,95%CI(-32.3,10.9).There were 12 cases(30.77%)in more than 10 mm Hg difference of TEE and RHC measurements.The bias between the PAPSr and PASP' in group A averged-2.7 mm Hg,95%CI(-21.9,16.5).There were 12 cases(30.77%)in more than 10 mm Hg difference of pulmonary artery systolic pressure after PVPG correction.The bias between the PAPSr and PASP in group A averged-2.9mm Hg,95%CI(-13.5,7.7).There were 1 cases(3.44%)in more than 10 mm Hg difference of TEE and RHC measurements.The bias between the PAPSr and PASP' in group B averged 1.9mm Hg,95%CI(-8.1,12).There were 1cases(3.44%)in more than 10 mm Hg difference of pulmonary artery systolic pressure after PVPG correction.2.The PASP of postoperative(24.15±3.78 mm Hg)is lower than the mearsurements of preoperative(32.00±8.75 mm Hg).(P<0.001)Conclusion : 1.Adjusted PASP calculated by tricuspid regurgitation pressure gradient method with pulmonary valve pressure gradient can improve the accuracy of echocardiographic estimates of PASP in ASD patients with the defect size>15 mm.2.The TR method by UCG can accurately predict the PASP in ASD patients with the defect size<15 mm alone,and the PVPG has no effect on the estimation of the PASP.3.ASD occlusion can reduce the pulmonary artery systolic pressures.