Effect Of Left Atrial Low-voltage On Post-operation Recurrence In Persistent Atrial Fibrillation Patient After Radiofrequency Catheter Ablation

Objective: Radiofrequency catheter ablation(RFCA)is currently accepted as a main approach for the treatment of atrial fibrillation(AF),but post-operation recurrence rate remains high.Among the proposed mechanisms for the recurrence,the effect of left atrial low-voltage has been received much attention in recent years.The aim of the present study is to evaluate the effect and,furthermore,the predictive value of the percentage of left atrial low-voltage on the post-operative recurrence;at the same time,the factors affecting the development of left atrial low voltage is also to be analyzed.Method:45 patients with persistent AF(PeAF)who were scheduled to receive RFCA in our department were enrolled.The patients were divided into recurrent and non-recurrent groups according to where the post-recurrence of AF after RFCA occurred or not.Carto 3 three-dimensional mapping system was applied to map left atrial voltage level,and <0.5 mV was used as a criterion for definition of low-voltage,and calculated left atrial low voltage/inner-superficial area proportion.There were four groups divided into>5%≤10%,>10%≤20%,>20%≤35%,>35% by left atrial low voltage/ inner-superficial area proportion.Different analysis was conducted for the left atrial low-voltage rate between recurrent and non-recurrent groups and,on the basis of the results,assessing whether it could be established as a risk factor and,furthermore,whether it has predictive value for the recurrence of postoperative AF by multiple logistics analysis;the similar approach was applied to assess the risk factors for development of left atrial low-voltage.Result:There were 11(24.44%)and 34(75.56%)patients,respectively,in the recurrent and the non-recurrent groups,and 9(81.8%)and 8(23.5%)patients with left atrial low-voltage,respectively,in the recurrence and the no-recurrence groups.The results of different analysis showed that the left atrial low-voltage rate was higher in the recurrent group than in the non-recurrent group.Besides,following factors that might affect post-recurrence of AF were also found to be higher in recurrent than non-recurrent groups: left atrial diameter(LAD),left ventricular end-diastolic volume(LVEDV),left ventricular end-systolic volume(LVESV),the ratio(E/e’)of peak mitral diastolic blood flow velocity(E)and the peak velocity of the mitral annulus early diastole(e’)and B brain natriuretic peptide(BNP).The results of univariate regression analysis showed that the above parameters were all proved as risk factors for post-operation recurrence of AF,but the results of multivariate regression analysis only support the rate of left atrial low voltage(OR=0.069,95%CI:0.006~0.851,P=0.037)and BNP(OR=0.996,95%CI: 0.993~1.000,P=0.046)to be the independent predictors.Further analysis for assessment of factors developing left atrial low-voltage revealed that both LAD and E/e’ have the association relationship with it,but only LAD(OR=0.749,95%CI: 0.576~0.973,P=0.013)was qualified as an independent predictor.Conclusion:Left atrial low-voltage may promote post-recurrence of AF after RFCA and,in this regard,proved to be an independent predictor;the same significance may be shared by the parameter of cardiac function,BNP.On the other hand,LAD contributes to the development of left atrial low-voltage and,to this end,established as an independent factor.