Study On The Shape And Function Of Right Heart In Patients With Chronic Pulmonary Artery Hypertension

Objective: To assess the shape and function of right heart in patients with chronic pulmonary artery hypertension and to search the main faction which influence the volume and function of right atrium.Methods:1 The study include 20 healthy participants as the control group and 57 patients with chronic pulmonary artery hypertension as the experimental group(.1)The patients were divided into three groups by pulmonary arterial systolic pressure(PASP).①low-grade pulmonary artery hypertension(LPH,n=20,mean age of 45.86±15.73years),②midrange pulmonary artery hypertension (MPH,n=20,mean age of 46.57±13.40 years) ,③severe pulmonary artery hypertension(SPH,n=20,mean age of 49.00±11.15 years).(2)Select the patient with RVEF>55% and Ea/Aa>1, and then compare it with control group.2 A set of color Doppler ultrasonic system (GE Vivid 7 ) was used, and the Echopac 6.2 workstation was available for quantitative analysis of TVI and SRI3 All echocardiography studies were performed with the subjects lying in the left lateral decubitus position connected with electrocardiogram (ECG). AND all the date was recorded in 3 continuous cardiac cycle and were stored in hardware for off-line analysis in Echo Pac.3.1 Doppler ECG(PW,CW,Color): (apical 4-chamber view)①In systolic phase, The gradient pressure between two sides of tricuspid valve can be measured, refering to the internal diameter and the collapse-rate of inferior vena cava (IVC), we can obtain pulmonary arterial systolic pressure(PASP).②In diastolic phase, the frequency spectrum of tricuspid valve- bloodstream can be obtained, and late-diastole peak velocity (Va) were measured.3.2 2D ECG: The thickness of RV anterior wall (RVAW) were measured in LV long axis view; Measure the diameter of tricuspid valve in apical 4-chamber view, and RA ejection force(RAEF) can be calculated; Using deplane Simpson's method, RV end-diastolic volume(EDV),RV end-systolic volume(ESV),and RV ejection fraction(RVEF) were get; Using deplane area- length method, maximal RA volume(Vmax), minimal RA volume(Vmin), pre-atrial contraction RA volume(Vprea) were measureed; Using the date above, we can calculate RA reservoir volume(RV), RA conduit volume(CV), RA contraction- chamber volume(CCV); If EDV,Vmax,Vmin,Vprea were divided by body surface area(BSA), we can get end-diastolic volume index(EDVI),maximal RA volume index(VmaxI), minimal RA volume index(VminI), pre-atrial contraction RA volume index(VpreaI) ,reservoir volume index(RVI),conduit volume index (CVI),contraction- chamber volume index (CCVI)。3.3 TVI ECG: (apical 4-chamber view) : Get apical 4-chamber view,enter TVI mode.(1) With the samp volume at RV free wall of valve ring, press PW, we can get tissue doppler frequency spectrum(S,E,A). Tei index and Ea/Aa were calculated (2) Make RA free wall exposed adequately and adjust the frame frequency 130±20 frames/s. Store the image in 3 continuous cardiac cycle for off-line analysis : Enter SRI mode. We can get the SRI of RA with the samp volume at RA free wall which have 5-8mm distance from tricuspid valve ring. Peak systolic RASR (RASRs), early diastolic RASR (RASRe), and late diastolic RASR (RASRa) were measured respectively.Result:1 Comparison of RV parametersRVAW and Tei index all increase as pressure of pulmonary artery rises. In RVEDVI, control group is different from MPH group, and also SPH group;and the same result is seen between LPH and SPH group. In terms of RVAW, significant difference between SPH and control group, LPH and SPH group, also control and MPH group. Speaking of Tei index, there is statistic difference between each group except LPH and control group.RVEF is first rising and then decreasing with the increasing of pulmonary artery pressure. RVEF of the SPH group falls dramatically,which has significant difference with the other three groups; the LPH group is higher than the control group, while the others have no difference。Ea/Aa drops with the rising of pulmonary artery pressure. And significant difference is seen respectively between SPH and the control group, SPH AND LPH group, MPH and control group, also MPH and LPH group.2 Comparison of RA parameters2.1 Comparison of RA volume parametersVmaxI, VpreaI and VminI all increase as pressure of pulmonary artery rises. There is statistic difference between each group except MPH and SPH group in VminI, VpreaI and also VminI.RVI and CCVI rise with the rising of pulmonary artery pressure, while CVI drops. In RVI, control group is different from MPH group, and also SPH group. In terms of CCVI, significant difference between SPH and control group, also SPH and LPH group. Speaking of CVI, there is statistic difference between SPH and control group, SPH and LPH group and also SPH and MPH group.2.2 Comparison of RA fuction parametersWith the rising of pulmonary artery pressure, RAEF rise, which has significant difference between each group.RASRs and RASRa increase as pressure of pulmonary artery rises. In RASRs, there is statistic difference between each group except MPH and LPH group. As similar as RASRs, except MPH and SPH group, Statistic difference between each group can be seen in RASRa. There is no significance between each group in RASRe.2.3 VmaxI and RAEF have statistic significant between control and patient group, whose RVEF>55% and Ea/Aa>1, while other parameters have no difference.3 correlation statistics3.1 correlation statistics between PSH and RA volume,also PSH and RA functionPSH is positively related to VmaxI, VpreaI, VminI, RVI, CCVI, RAEF and RASRs. PSH is negatively related to CVI and RASRa, and have a significant association with RAEF, RASRs and RASRa.3.2 correlation statistics between RA volume and Ea/AaRAEF is negatively related to Ea/Aa, while Ea/Aa is positively related to RASRa and CVI.3.3 correlation statistics between RA function and Ea/AaRVEF is negatively related to RVI,CCVI,RAEF and RASRs, inversely, RVEF is positively related to CVI and RASRa . RVEF have a significant association with RASRs.4 Screening main factors influencing VpreaI and RAEF4.1 The influential factor of Viprea includes RVEDVI,RVAW,Ea/Aa and illness course4.2 VpreaI and PSH are the main factors associated with RAEF.Conclusion:In patients with chronic pulmonary artery hypertension, it is found that compensatory reconstruction takes place in right ventricle. The compensation and injury coexist of RV function take place at the same time .In patients with chronic pulmonary artery hypertension the volume and function of RA changed, and some index of which have relation to PSH,RVEF or Ea/Aa. The index of SRI can be used to evaluate RA function.