A Clinical Study Of Echocardiography Quantitative Evaluation Of Cardiac Structure Function In Patients With Atrial Fibrillation Before And After Radiofrequency Ablation

Background:The structure and function of the left atrium is of great significance for the occurrence and prognosis of atrial fibrillation(AF).At present,the guidelines recommend that radiofrequency ablation of atrial fibrillation is a kind of invasive treatment,and the left atrial structure and functional changes of patients are also highly valued.Objective:To evaluate left atrial structure and systolic and diastolic function in patients with paroxysmal atrial fibrillation(PAF)using two-dimensional speckle tracking imaging(STI)and real-time three-dimensional imaging technology(RT-3D)combined conventional echocardiography.The aim is to explore the application value of this technique in evaluating left atrium function and the effect of radiofrequency ablation on the structure and function of the left atrium in patients with AF.Methods:32 cases of PAF patients with successful catheter ablation were selected,and 18 healthy subjects were selected as control group.The patients were studied at baseline,1 month and 6 months past radiofrequency ablation with routine thoracic echocardiography,pulse doppler blood flow spectrum,tissue doppler myocardial imaging(TDI),STI and RT-3D.We use echocardiography to measure inner diameter of the left atrium including left atrium anterior and posterior diameter(LAAPD),left atrium upper and down diameter(LAUDD)and left atrium left and right diameter(LALRD),left ventricular end-diastolic diameter(LVEDD),left ventricular end-systolic diameter(LVESD)and calculate the left ventricular ejection fraction(LVEF).The transmitral flow velocity of early diastolic filling wave(E)and later filling wave(A)of mitral annulus were measured.Pulmonary vein Ar wave velocity was measured.Doppler myocardial velocity e’ and a’ from septal mitral annulus were obtained.The ratio of E/e’ was used as the filling pressure of left ventricle.The peak systolic(SRs),early-diastolic(SRE)and late-diastolic(SRA)strain rate of left atrial segment and globle longitudinal strain rate(GLSR)were measured by STI.Left atrial minimum volume(LAVmin),left atrial maximum volume(LAVmax)and left atrial presystolic volume(LAVp)were obtained using RT-3D.Thus left atrial ejection fraction(LAEF),left atrial active ejection fraction(LAAEF)and left atrial passive ejection fraction(LAPEF)were calculated.Results:Compared with control group,in PAF before radiofrequency ablation,LA inner diameter and volume increased,the ratio of E/e’ increased,but LAEF.Ar wave velocity.doppler myocardial velocity e’ and a’ decreased.There was no significant difference in LVEDD,LVESD and LVEF.Either the systolic strain or diastolic strain rate of LA was lower.There were 8 cases of recurrence after radiofrequency ablation in 32 PAF patients.Compared with preoperative,in sinus rhythm group after 1 month,LA inner diameter and LAVmin decreased,but there was no significant difference in LAVmax、LAVp、LAEF、LAAEF、LAPEF as well as strain rate.In recurrence group 1 month later,LA inner diameter、volume and functional parameter by STI and RT-3D did not show significant difference.In sinus rhythm group 6 month later,LA inner diameter and volume significantly decreased,however,LAEF、LAAEF and LAPEF increased.At the same time,SRs、SRE、SRA of lateral base and middle segments,SRs、SRE、SRA of septal base segment,SRE、SRA of septal middle segment and GLSR increased.In recurrence group after 6 months,LA volume was larger,LAEF and LAAEF were lower than those before radiofrequency ablation,but there was no significant difference in LA strain rate.In sinus rhythm group 6 months later,LA inner diameter and volume decreased,LAEF and LAAEF increased,while SRs、SRE、SRA of lateral base segment,SRs、SRE of lateral middle segment,SRs、SRE、SRA of septal base segment,SRs、SRA of septal middle segment and GLSR increased compared with those parameters 1 month later.However,in patients with recurrence of AF 6 months later,LA structural and functional parameters did not changed significantly compared with those after 1 month.1 month later,compared with sinus rhythm group,LA volume increased,LAEF and LAAEF decreased,the strain rate decreased,but this change of strain rate was not significant.6 months later,compared with sinus rhythm group,LA inner diameter and volume were larger,LAEF、LAAEF and LAPEF were lower.SRs、SRE of lateral base segment,SRs、SRE、SRA of lateral middle segment,SRs、SRE、SRA of septal base segment,SRs、SRA of septal middle segment and GLSR decreased.Conclusion:Two-dimensional speckle tracking imaging and real-time three-dimensional imaging technology can be used to quantitatively analyze the left atrial structure and function before and after radiofrequency ablation of paroxysmal atrial fibrillation.LA inner diameter and volume increase,but LA global and segmental strain rate decrease in patients with PAF,which implicated the reservoir,conduit and pump function of LA impaired in varying degrees.After a successful radiofrequency ablation,we got the conclusion of the rapid reversion of LA remodeling and significant improvement of LA function.Background:Atrial fibrillation is often associated with right ventricular dysfunction.The degree of impairment of right heart function is related to the severity of atrial fibrillation,and it has important guiding value for the choice of treatment and prognosis.At present,there are few studies on echocardiographic evaluation of right ventricular function in patients with atrial fibrillation.Objective:The echocardiographic right heart parameters recommended by the ASE guide were used to evaluate the differences in right heart structure and function in different types of atrial fibrillation.Right ventricular structure and function were evaluated before and after radiofrequency ablation for paroxysmal atrial fibrillation.The aim is to explore the application value of echocardiographic right heart parameters in evaluating right ventricular structure and function and the effect of radiofrequency ablation on right cardiac contractile function in patients with PAF.Methods:49 cases of outpatients and inpatients who were diagnosed as atrial fibrillation in Xuzhou Medical University Affiliated Hospital were collected including 32 cases of paroxysmal atrial fibrillation and 17 cases of persistent atrial fibrillation.The patients of SAF were studied at baseline and the patients of PAF were studied at baseline,1 month and 6 months past radiofrequency ablation.At the same time,18 healthy persons with comparable sex and age were selected as control group.All patients underwent routine thoracic echocardiography,pulse doppler blood flow spectrum,tissue doppler myocardial imaging(TDI),STI and RT-3D.We use two-dimensional echocardiography to measure left atrium anterior and posterior diameter(LAD),left ventricular end-diastolic diameter(LVEDD)and calculate the left ventricular ejection fraction(LVEF),right ventricle diameter(RVD),right atrium diameter(RAD),right ventricular end-diastolic area(RVEDA),right ventricular end-systolic area(RVESA)and right ventricular fractional area change(FAC).Tricuspid annular plane systolic excursion(TAPSE)was measured by M-mode echocardiography.Doppler myocardial velocity S’ from tricuspid annulus of right ventricle lateral wall was obtained.Right heart myocardial performance index(MPI)was calculated by tissue doppler imaging.Pulmonary artery systolic pressure(PASP)was estimated from the tricuspid valve(TRV)using the Bernoulli equation in patients with TRV regurgitation.The peak systolic strain rate(SR)of right ventricle of segments and globle longitudinal strain rate(GLSR)were measured by STI.Right ventriclar minimum volume(RVVmin)and right ventriclar maximum volume(RVVmax)were obtained using RT-3D.Thus right ventriclar ejection fraction(LAEF)was calculated.Results:Compared with control group,LAD was larger in SAF than that in PAF,but LVEDD and LVEF did not show significant difference.In SAF,S’、FAC、TAPSE and RVEF decreased,but MPI、TRV、PASP、RVVmin and RVVmax increased.The strain rate values in all segments of RV free wall,in right septal base and middle segments and GLSR lowered.In PAF,TAPSE and RVEF decreased,while the strain rate also decreased in free wall’s base and middle segments,right septal base and middle segments and GLSR.In SAF group,LAD、RVD、RAD、RVEDA、RVESA、RVVmin、RVVmax、MPI、PASP were larger,TAPSE was lower,the strain rates of free wall’s base and middle segments,right septal base and middle segments and GLSR were lower than those in PAF group.After successful radiofrequency ablation in patients with PAF,two parameters of TAPSE and RVEF were higher in sinus rhythm group after 1 month and 6 months than those before radiofrequency ablation.FAC increased and MPI decreased 6 months later.1 month later,the strain rate values in free wall’s base and middle segments,right septal base segment and GLSR improved.6 months later,the strain rate values in free wall’s base and middle segments,right septal base and middle segments and GLSR improved.The strain rate values improved in free wall’s base and middle segments,right septal base segment and GLSR increased after 6 months compared with those 1 month later.In patients with recurrence of AF,1 months later,the strain rate values in free wall’s base segment and right septal base segment and GLSR were higher than those before radiofrequency ablation,but 6 months later,there was no significant difference in all right heart parameters.The strain rate values in free wall’s base segment and right septal base segment after 6 months were lower than those after 1 month.1 month later,TAPSE and the strain rate values in free wall’s middle segment were lower in patients with recurrence of AF than those in sinus thythm group.6 months later,TAPSE,RVEF,as well as the strain rate values in free wall’s base and middle segments,right septal base segment and GLSR in patients with recurrence of AF decreased compared with the sinus thythm group.Conclusion:The structure and function of the right ventricle in patients with atrial fibrillation can be quantitatively analyzed with new ultrasonic techniques of two-dimensional speckle tracking imaging and real-time three-dimensional imaging technology.Right ventricular volume indexes increase and function indexes decrease in patients with atrial fibrillation.Furthermore,the two dimensional longitudinal strain index of the right ventricular is more sensitive than other functional indicators.The maintenance of sinus rhythm after ablation can improve the function of right heart in patients with paroxysmal atrial fibrillation.