An Ultrasonographic Study On Atrial Electrical And Mechanical Properties And The Relationship Between Heart Rate Variability And Tricuspid Annulus Displacement In Patients With Rheumatoid Arthritis

Part One An Ultrasound Study on Atrial Electrical and MechanicalProperties in Patients with Rheumatoid ArthritisObjective: We sought to investigate the atrial function and atrialelectromechanical contraction properties by conventional and tissue velocityechocardiography in patients with rheumatoid arthritis.Methods:70patients with RA and60age-and sex-matched healthyvolunteers come from Affiliated Hospital of North Sichuan Medical Collegewere enrolled in the study. We measured their height,weight and bloodpressure, calculated the body mass index(BMI)，collected venous blood toassay fasting serum lipids, blood glucose and correlative biochemical indexesin Rheumatoid Arthritis, The disease activity score (DAS28) based on thenumber of tender and swollen joints (n=28) were recorded for each RAsubject. Using transthoracic echocardiography, the size of atrium andventricular, wall thickness, valve orifice hemodynamic parameters weremeasured. The left ventricular ejection fraction was obtained in apical fourchamber view using Simpson s method. TVI was performed to assessintraatrial and interatrial electromechanical contraction function. Maximumatrial volume(AV max),minimum atrial volume(AV min) and the volume atonset of atrial systole (P-volume)(AVp) were corrected by body surfacearea(BSA), atrial active,passive and total emptying volumes and emptying rate were calculated. Meanwhile,the onset of P wave on the surface ECG toonset of A wave in atrial myocardium was used as the PA interval andrepresented the atrial electromechanical delay were measured by TVI andsynchronous ECG, the atrial function, peak A wave velocity of atrial wallmovement and time up to peak were compared.Result: The patients with rheumatoid arthritis had significantly higherLAD,LAVImin， RAVImin， eLAVIact%， RAVIact%（P<0.05）， lowerLAVIpass，RAVIpass，LAVItotal，RAVItotal，LAVIpass%，eLAVIpass%（P<0.05）than controls. Moreover, the velocity of IAS，LALW was lower,RAFW was higher（P<0.05）, the time to peak velocity of IAS、LAASW waslonger (P<0.05), the time intervals of RAFW、IAS、LALW、LAAW、LAIWand LAPW between onset of P wave and onset of A wave was significantlydelayed compared with healthy controls（P<0.05）. The electromechanicalcontraction time difference between left intraatrial and interatrial increasedand the time difference between LAASW and LAPW,RAFW and LALW wassignificantly different in patients with rheumatoid arthritis（P<0.05）.Conclusion:1）In patients with rheumatoid arthrit is,the velocity of partof atrial wall decline, the time to peak velocity delayed, intraatrial andinteratrial mechanical contraction time is significantly delayed, andmechanical desynchrony exists in part of atrial wall, the atrial functiondecreased. These suggests that myocardial function and atrialelectromechanical properties alter, atrial function is disturbed in RA patients,2)Right atrial reservoir function increase,conduit function and the total outputdecrease,which is similar with the change of left atrial. Part two A Study of the Relation between Heart Rate Variability andTricuspid Annular Plane Systolic Excursion in Patients with RheumatoidArthritisObjective: In this study we aimed to investigate the relation betweenheart rate variability(HRV) and tricuspid annular plane systolicexcursion(TAPSE) in patients with rheumatoid arthritis using Holter andechocardiography.Methods:20consecutive patients with RA were compared with20ageand sex-matched controls in the Affiliated Hospital of North Sichuan MedicalCollege. We measured their height,weight and blood pressure, calculated thebody mass index(BMI), collected venous blood to assay fasting serum lipids,blood glucose and correlative biochemical indexes in Rheumatoid Arthritis,The disease activity score (DAS28) based on the number of tender andswollen joints (n=28) were recorded for each RA subject. Using transthoracicechocardiography, the size of atrium and ventricular, wall thickness, valveorifice hemodynamic parameters were measured. The left ventricular ejectionfraction was obtained in apical four chamber view using Simpson s method.we measured right ventricular end-diastolic area(RVEDA)，right ventricularend-systolic area(RVESA) and calculated right ventricular fractional areachange(RVFAC）,TAPSE were measured by M-mode echocardiography inapical four chamber view, PW-TDI was performed to obtain the maximalvelocity of early diastolic of tricuspid annular(E),the maximal velocity of end diastolic of tricuspid annular(A), E/A ratio, right ventricular isovolumiccontraction time(RV IVCT),isovolumic relaxation time(RV IVRT) andejection time(RV ET), For calculation of myocardial performance index ofright ventricle(RV MPI). RV MPI was calculated according to followingformula:[(RV IVRT)+(RV IVCT)]/RV ET. Maximum atrial volume(AVmax),minimum atrial volume(AV min) and the volume at onset of atrialsystole (P-volume)(AVp) were corrected by body surface area(BSA), atrialactive, passive and total emptying volumes and emptying rate were calculated.Meanwhile, All patients underwent24-hour Holter monitoring, heart ratevariability was assessed, the standard deviation of all normal RRintervals(SDNN),the standard deviation of the5-minute average NNintervals(SDANN),the standard deviation of the5-minute average NNintervals index(SDANNindex),the percentage of intervals＞50ms differentfrom preceding interval（pNN50）,square root of the mean of the squares ofsuccessive NN interval differences（rMSSD) were recorded.Results: Patients with RA had significantly lower LVEF, E/A, TAPSE,RV ET, higher A, RV IVRT, RV MPI as compared with controls（P<0.05），There was no significant difference in atrial function parameters betweenpatients with RA and controls (all P>0.05).The TAPSE was positivelycorrelated with SDNN, pNN50, rMSSD, SDANN(r=0.522， P=0.018，r=0.513，P=0.021，r=0.482，P=0.031，r=0.553，P=0.026，respectively),WhilstRV FAC was positively correlated with SDNN, SDNNindex, pNN50, rMSSD（r=0.493，P=0.027，r=0.563，P=0.010，r=0.610，P=0.004，r=0.590，P=0.006,respectively).Moreover, RAVImax and RAVItotal were positivelycorrelated with SDANN(r=0.510，P=0.044，r=0.580，P=0.019, respectively)， RAVIact was positively correlated with SDNN and SDANN(r=0.463，P=0.040，r=0.560，P=0.024,respectively).Conclusion: HRV reflects sympathovagal balance and has previouslybeen used to define the role of autonomic nervous system activity. TAPSE asan index of RV systolic function in a variety of pathologic conditions,Thisstudy demonstrate that the change of RV systolic function can downregulatethe autonomic nervous system reaction.