A Preliminary Study Of The Assessment By Echocardiography In Pulmonary Artery Pressure And Pulmonary Vascular Resistance

Part1Echocardiography Tricuspid Regurgitation and Multi-parameterComprehensive Method to Evaluatethe Accuracy of the Pulmonary Artery PressureObjective：Echocardiography tricuspid regurgitation was explored with multi-parametersynthetic method to evaluate the accuracy and feasibility of the pulmonary arterypressure.Materials and methods:Respectively using echocardiography and right cardiaccatheterization in78patients with suspected diagnosis of pulmonary hypertensiondetecting pulmonary artery systolic pressure. According to the different levels ofpulmonary arterial systolic pressure of RHC，patients were divided into four groups，including no PH(PASP<30mmHg), mild PH(30mmHg≤PASP<50mmHg), moderatePH(50mmHg≤PASP<70mmHg)and severe PH(PASP≥70mmHg). Echocardiographypatients with tricuspid regurgitation pressure gradient, pulmonary valve regurgitationpressure gradient,, pulmonary artery blood flow acceleration time (AT), the innerdiameter of pulmonary artery, the right room inside diameter, right ventricular wallthickness and interventricular septum curvature. Respectively using the method oftricuspid regurgitation and multi-parameter synthesis method, evaluating RHC’s testresults as the gold standard, analyzed echocardiographic accuracy and feasibility of thetwo methods of detecting PASP.Results: Pearson correlation analysis showed that using echocardiographic tricuspidregurgitation measurement results (51.47±31.82)mmHg and right cardiaccatheterization measurements (58.96±31.68)mmHg was highly correlated, thecorrelation coefficient was0.836(P<0.01). According to Bland-Altman’s analysis, tricuspid regurgitation and the right cardiac catheterization measured value of biasaveraged4.8,95%CI-29.7~20.0. There were32cases (41.0%) in more than10mmHg difference of PASP measurement of TTE and RHC, including underestimated23cases (29.5%) and overestimated9cases (11.5%). The extent of TTE’sunderestimated or overestimated PASP was no statistically significant differencebetween [(10.96±8.78)mmHg and (9.04±8.46)mmHg,P=0.865). According to thePASP severity grading diagnosis classification, using tricuspid regurgitation inassessing PASP is19.23%undervalued and10.26%overvalued, leading pulmonaryartery pressure to29.49%severity grading classification error. Using multi-parametersynthesis evaluation of pulmonary artery pressure is8.97%undervalued and1.28%overvalued, leading pulmonary artery pressure to10.26%severity grading classificationerror.Conclusion: Echocardiographic evaluation of pulmonary artery pressure is feasible, andthe multi-parameter synthesis method accuracy higher than tricuspid regurgitation. Part2The Consistency Analysis of Doppler EchocardiographyEstimating Pulmonary Vascular Resistance Noninvasively Comparewith the Right Cardiac Catheterization’s MeasurementObjective: Comparing testing results of doppler ultrasound and right cardiaccatheterization(RHC) to analysis the feasibility of noninvasive assessment of pulmonaryvascular resistance(PVR) by doppler echocardiography.Materials and methods: Twenty-eight cases of suspected diagnosis of pulmonaryhypertension (PH) patients were measured time-velocity integral of the right ventricularoutflow tract (TVIRVOT) and tricuspid regurgitation velocity (TRV) by dopplerultrasound. And using TRV/TVIRVOTx10+0.16and TRV2/TVIRVOTx5.19-0.4(doppler formula1and2) calculated PVR respectively. At the same time, pulmonaryarterial pressure and cardiac output were detected by the right cardiac catheterization. PVR was obtained by using the Fick method. According to the results of rightcardiac catheterization measuring PVR≤6Wood or>6Wood divided the patientsinto two groups.Results: PVR calculated by doppler ultrasound using formula1and2and rightcardiac catheterization in not grouping or grouping conditions were highly correlated(r=0.881、0.895、0.925, P<0.01). But PVR tested by doppler ultrasound formula1hadgood consistency with catheter only in group PVR≤6Wood. Doppler ultrasoundmeasurement formula2measured PVR had no significant consistency differencewith catheter in each group. Further Bland&Altman analysis revealed that formula2measured PVR in group PVR≤6Wood measuring a biger bias than formula1comparedwith catheter. As TRV/TVIRVOT>0.19for the cutoff value to distinguish PVR>6Woodhas highly sensitivity (100%) and specificity (80%).Conclusion: Doppler echocardiography can be used for rapid, noninvasive, quantitativeassessment of pulmonary vascular resistance, but in clinical work we should pay moreattention to different degrees of increased PVR patients should use different PVRcalculation formulas. Part3Measuring Isovolumic Contraction Peak Velocityat the Tricuspid Annulus by Doppler Tissue Imaging to Assess Right HeartFunction in Patients with Pulmonary HypertensionObjective：The aim of this study was to evaluate the feasibility and accuracy of theIVCv’s prognostic value of right heart function of pulmonary hypertension byechocardiography and Doppler tissue imaging.Materials and methods:41patients with suspected diagnosis of pulmonaryhypertension(PH) were measured isovolumic contraction peak velocity (IVCv) at thetricuspid annulus by echocardiography and Doppler tissue imaging.Also measured right heart systolic function parameters such as tricuspid annular plane systolicexcursion(TAPSE)、 peak systolic velocity(PSv)、 right ventricular fractional areachange(RVFAC).And pulmonary artery pressure detected by right-heart catheterization(RHC). According to Different levels of pulmonary arterial systolic pressure, patientswere grouped4to compare and analyze if any significance can be found, includingwithout PH, mild PH, moderate PH and severe PH. Then, sensitivity and specificity ofpulmonary hypertension and right heart impairment’s diagnosis were assessed by ROCcurves. Last, correlation analysis of the data was performed.Results: IVCv was significantly and positively correlated with the right heart systolicfunction parameters, such as TAPSE(r=0.573, P<0.001)、PSv(r=0.757, P<0.001)、RVFAC(r=0.557, P<0.05). Negative correlation exists between IVCv and PASP(r=-0.74, P<0.001). The average of the study’s group included without PH, mild PH,moderate PH and severe PH were13.83±3.56cm/s,10.11±1.36cm/s,8.70±2.21cm/sand5.80±1.03cm/s respectively. The level of IVCv was obviously lower in severe PHgroup than those in without PH, mild PH, and moderate PH, differences weresignificant(P<0.05). The levels of IVCv were increased obviously in without PH thanthose in mild PH,and moderate PH(P<0.01).There were no diferences in IVCv betweenmild PH,and moderate PH(P>0.05). With common echocardiographic assessment of thelower limit right ventricular systolic function parameter for standard (TAPSE<16mm,PSv<10cm/s, RVFAC<35%), IVCv<6.5cm/s’ diagnosis of right ventricular systolicfunction reduction’s sensibility were91%,96%,87%and specificity were70%,53%,77%respectively.Conclusion: Measurement of IVCv by Doppler tissue imaging, an objective methodusing an new parameter of patients with the diagnosis of right ventricular systolicfunction reduction. It is worth further study and has a significance to be popularized inclinic.