Evaluation Of Left Atrial Remodeling In Patients With Atrial Fibrillation After Different Ablation Strategies By Two-dimensional Speckle Tracking Imaging And Real-time Three-dimensional

Objective To evaluate the impact of two kind of ablation methods on left atrial(LA)remodeling in patients with atrial fibrillation(AF)using two-dimensional speckle tracking imaging(2D-STI)and real-time threedimensional echocardiography(RT-3DE).Methods Forty-nine patients with AF were devided into radiofreque ncy ablation(RFA)group(n=30)and cryoballoon ablation(CBA)group(n=19).All subjects were underwent Echocardiographic examination before,a nd at 3rd day,1st month after ablation.The global and regional left atrial peak systolic strain and strain rate,peak early diastolic striain and stra in rate,peak late diastolic strain and stain rate,left atrial electromechan ical conduction time were measured by 2D-STI.The mean LA electromec hanical conduction time(m EMT),the standard deviation of LA electromec hanical conduction time(EMT-SD)were calculated.The LA maximal,mini mal and pre-systolic volume(LAVmax,LAVmin,LAVp),LA maximal volume index,minimal volume index(LAVImax,LAVImin),LA total ejectio n fraction(LATEF),LA passive ejection fraction(LAPEF),LA active ejec tion fraction(LAAEF)were measured by RT-3DE.Results(1)Before,and at 3rd day,1st month after ablation,there w as no statistical significance in LAD,LAVImax,LAVImin,LATEF,LAA EF,LAPEF between RFA group and CBA group(P>0.05).Before and 1s t month after ablation,there was no statistical significance in global an d regional left atrial strain and strain rate between RFA group and CBA group(P>0.05).Compared with the RFA group,Sa,SRa in each wall of LA,m Sa,m SRa decreased in CBA group(P<0.05)3 days after ablation.(2)Comparing with pre-operative,RFA group showed LAD,LAVImax,L AVImin increased and LAAEF,the global and regional strain and strain rate decreased(P<0.05)3 days after ablation.Left atrial m EMT,EMT-SD increased(P<0.05)3 days after ablation.After 1 month ablation,RFA group showed LAD,LAVImax,LAVImin decreased(P<0.05),strain and strain rate in anferior wall of LA and m EMT decreased(P<0.05).Compa red with 3 days after ablation,RFAgroup showed LAD,LAVImax,LAVI min,m EMT,EMT-SD decreased and LATEF,LAAEF,LAPEF increased(P<0.05)1 month after ablation.Strain and strain rate in anterior,lateral,inferior,spetal wall of LA and m Ss,m Sa,m Se,m SRs,m SRa,m SRe incre ased(P<0.05)1 monthafter after ablation in RFA group.(3)Comparing wit h pre-operative,CBA group showed LAD,m EMT,EMT-SD increased and LATEF,LAAEF decreased(P<0.05)3 days after ablation.Strain and strain rate in each wall of LA and global Strain and strain rate decreased(P<0.05)3 days after ablation in CBA group.1 month after ablation,LA D,LAVImax,LAVImin,Ss,Sa,SRs,SRa in anferior wall of LA,m EMT decreased(P<0.05).Compared with 3 days after ablation,CBA group sho wed LAD,LAVImax,LAVImin decreased(P<0.05)and LATEF,LAAEF,LAPEF increased(P<0.05)1 month after ablation.The global and regio nal left atrial strain and strain rate increased(P<0.05)and m EMT,EMT-SD decreased(P<0.05)1 month after ablation.Conclusions(1)There was no significant difference between the two methods of RFA and CBA for atrial structure,function and electrical remo deling in patients with atrial fibrillation after 1 month ablation.(2)3 days a fter ablation,AF patients in RFA group and CBA group were be in a dete rioration,LA enlarged and the reservoir,conduit,pump function of LA im paired.Compared with the RFA group,the pump function of LA significant decreased in CBA group.(3)1 month after ablation,LA electrical and struct ural remodeling is reversible.There was no significant difference in LA fu nction between pre-ablation and 1 month after ablation,and strain and stra in rate in anferior wall of LA was still decreased Comparing with pre-op erative.