A Clinical Study Of The Clinical Characteristics, Long-term Efficacy Outcomes And Characteristics Of Recurrent Secondary Surgery In The Treatment Of Persistent Atrial Fibrillation With Cryoballoon Ablation

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The clinical characteristics and the features of acute procedure period of cryoballoon ablaltion of persistent atrial fibrillationObjective:Cryoballoon ablation of paroxysmal atrial fibrillation has been demonstrated with the reliable safety and efficacy,while the study about the application of cryoballoon ablation of persistent atrial fibrillation for achieving the pulmonary vein isolation(PVI)alone is relatively scarce.The present study sought to retrospectively investigate the clinical characteristics associated with the mapping and ablation during cryoballoon ablation of persistent atrial fibrillation.Methods:The study was designed to retrospectively analyze the patients who were admitted to the Arrhythmia Center of Chinese Academy of Medical Sciences Fuwai Hospital and underwent the first-generation or second-generation cryoballoon ablation of persistent atrial fibrillation from the January 2015 to August 2018.The procedure endpoint was the success of pulmonary vein isolation(PVI)without adding the additional predesigned ablation linear or fragmentation ablation during the procedure.The target pulmonary veins with the cryoablation failure would undergo the touch-up radiofrequency ablation for reaching the acute period PVI.The cavotricuspid isthmus(CTI)would be ablated to reach the CTI bidirectional conduction block if patients in combination with typical atrial flutter(AFL).In addition,the analysis of the clinical characteristics of the enrolled patients and the acute period indexes of cryoablation were conducted.Results:A total of 354 patients with symptomatic persistent atrial fibrillation who received cryoballoon ablation were enrolled to analyze in this study,with the mean age of 56.0±10.0 years old and 279(78.8%)males.The mean duration of persistent atrial fibrillation was 8.8±11.4 months.Forty(11.3%)patients had a history of stroke or transient ischemic attack(TIA)events before admission.The multivariate logistic regression analysis showed that hypertension,diabetes,left atrial anteroposterior diameter(LAAPD)?44mm,and CHA2DS2-VASc score>3 were independent risk factors for the stroke or TIA events(OR=3.7,95%CI:1.1-12.4,OR=7.8,95%CI:1.9-32.6,OR=2.9,95%CI:1.0-8.0 and OR=116.7,95%CI:32.6-417.3,P value were 0.035,0.005,0.043,and<0.001,respectively).The application times,procedure time,radiation exposure time and radiation dose of second-generation cryoballoon were superior to those of first-generation cryoballoon.The right inferior pulmonary veins(RIPVs)had the lowest recording rate of pulmonary vein potential(PVP)(only 70.6%)during the cryoballoon ablation.It was worth noting that RIPVs had the highest failure rate of acute cryoablation and PVP recording among the pulmonary veins.The incidence of vagal reflex during the cryoballoon ablation was 9.3%at the left-sided pulmonary veins,especially left superior pulmonary veins(LSPVs).In addition,the right superior pulmonary veins(RSPVs)had the proportion of 2.3%occurring a transient phrenic nerve palsy.No severe procedure-related complications occurred throughout the cryoablation procedure.Conclusion:Cryoballoon ablation for the treatment of persistent atrial fibrillation has a good safety and success rate of PVI in the acute procedure period.The acute period efficiency of pulmonary vein isolation with application of second-generation cryoballoon is superior to the first-generation cryoballoon.RIPVs had the highest failure rate of acute cryoablation and PVP recording among the pulmonary veins.The incidence of vagal reflex during cryoballoon ablation of left-sided pulmonary veins is relatively high,RSPVs are prone to the transient phrenic palsy.Part ? The long-term therapeutic effect and the risk factors of the recurrence of cryoballoon ablaltion of persistent atrial fibrillationObjective:Pulmonary vein isolation(PVI)considered as the cornerstone of catheter ablation of atrial fibrillation is extensively applied for treating the paroxysmal atrial fibrillation,while the safety and efficacy about cryoballoon ablation of paroxysmal atrial fibrillation have been demonstrated to be noninferior to radiofrequency ablation.The different ablation strategy for treating the persistent atrial fibrillation results in the heterogeneous success rate owing to the nature of the complex pathogenesis.Furthermore,cryoballoon ablation of persistent atrial fibrillation for PVI alone is still controversial.Methods:This study retrospectively analyzed the patients with persistent atrial fibrillation without structural heart disease who underwent the treatment of second-generation cryoballoon ablation for PVI in the Arrhythmia Center of Chinese Academy of Medical Sciences Fuwai Hospital from the august 2016 to august 2018.On the basis of the analysis of the follow-up study results,Kaplan-meier method were used to analyze the long-term eggect of patients with different duration of persistent atrial fibrillation after cryoballoon ablation.Cox regression model was used to analyze the risk factors for atrial fibrillation recurrence.Analysis of the P-wave duration of the inferior lead ? and the negative P-wave of the precordial V1 lead after restoring the sinus rhythm.The effect of the recurrence in the 3-month blanking period on the long-term procedural outcome was also compared using the survival curve.Results:A total of 329 patients with persistent atrial fibrillation who had the completion of the post-procedural follow-up were enrolled for the analysis in this study,with the mean age of 55.5±9.5 years old and 257(78.1%)males.The mean duration of persistent atrial fibrillation was 8.4 ±10.1 months.Thirty-nine(10.9%)patients had the history of stroke or TIA prior to the procedure.After a median follow-up of 30.0 months(quartile interval:range 10.0 to 43.0 months),Kaplan-Meier survival analysis showed that the accumulative survival rate of freedom from atrial fibrillation recurrence at 12,24,and 30 months were 71.0%,58.5%,and 54.9%,respectively.Analysis of the different disease course of persistent atrial fibrillation showed that the recurrence rate of atrial fibrillation after cryoballoon ablation in patients with early persistent atrial fibrillation was significantly lower than that of patients with persistent atrial fibrillation lasting more than 3 months.The accumulative survival rate of freedom from atrial fibrillation recurrence of patients with early persistent atrial fibrillation and long-standing persistent atrial fibrillation at 12,24,and 30 months were 74.1%vs 64.9%,60.2%vs 65.9%,and 42.6%vs 40.4%,respectively(P<0.023).With a restoring sinus rhythm after the cryoballoon ablation,patients with persistent atrial fibrillation lasting more than 3 months had the significant long P-wave duration in the inferior ? lead comparing with patients with early persistent atrial fibrillation(140.8±22.9ms vs 135.3±22.6ms,P=0.032).Multivariate Cox regression analysis of hypertension,coronary heart disease,diabetes mellitus,left atrial diameter?42mm,gender,age?60years old,inferior ? lead with a bipolar P-wave,BMI?26Kg/m2,and persistent atrial fibrillation duration lasting more than 3 months showed that the duration of persistent atrial fibrillation and the left atrial anteroposterior diameter?42mm were the main risk factors for atrial fibrillation recurrence after cryoballoon ablation(HR=1.89,95%CI:1.01-1.4,P=0.042 and HR=3.6,95%CI:2.4-5.35,P<0.001).Atrial fibrillation recurrence in the 3-month blank period after cryoballoon ablation was suggestive of the poor long-term survival rate of freedom from atrial fibrillation recurrence.Kaplan-Meier survival analysis also showed that the survival rate of freedom from recurrence at 12 and 30 months between the two group with or without recurrence in the blanking period was 45.6%vs 79.8%and 21.9%vs 66.0%(HR=7.2,95%CI:4.7-10.9,P<0.0001).Conclusion:Cryoballoon ablation is safe and effective for the treatment of persistent atrial fibrillation.The long duration of persistent atrial fibrillation and enlarged left atrium are risk factors for predicting the atrial fibrillation recurrence after cryoballoon ablation.Recurrence rate in the blank period was high after cryoballoon ablation of persistent atrial fibrillation,and the recurrence in the blanking period would be significantly associated with the long-term recurrence.Part ? The redo procedure characteristics of the recurrent atrial fibrillation after the cryoballoon ablation of persistent atrial fibrillationObjective:The recurrence of atrial fibrillation after cryoballoon ablation of persistent atrial fibrillation are the conundrum and chanllenge for the treatment of persistent atrial fibrillation,while the stratergy of the redo procedure for the relapse remain controversial and the mechanism of the relapse is still lack of evidence.The present study sought to analyze the characteristics of second ablation procedure and hope to find more evidence for the treatment stratergy of the relapse of atrial fibrillation following the prior cryoballoon ablation of persistent atrial fibrillation.Methods:This study retrospectively analyzed patients who underwent the cryoballoon ablation of persistent atrial fibrillation with atrial fibrillation recurrence and had readmission to receive the redo procedure in the Arrhythmia Center of Chinese Academy of Medical Sciences Fuwai Hospital from the January 2017 to June 2019.The analysis included the type of recurrent arrhythmias,the distribution of pulmonary vein-left atrial conduction recovery mapped during the redo procedure,the change of atrial fibrillation burden and the relapse after the redo procedure.Results:A total of 24 patients with recurrent atrial fibrillation who underwent the redo procedure after cryoballoon ablation of persistent atrial fibrillation were included,with the mean age of 50.8±9.4 years old and 20(83.3%)males.The mean preprocedural duration of atrial fibrillation was 7.0±7.9 months and the median follow-up of 9.0 months(quartile range:5.0 to 18.0 months).The type of recurrent arrhythmias were 13(54.2%)cases of paroxysmal atrial fibrillation,7(29.2%)cases of persistent atrial fibrillation secondary to paroxysmal atrial fibrillation,3(12.5%)cases of paroxysmal atrial fibrillation in combination with typical atrial flutter(AFL),and 1 case(4.1%)of atypical atrial flutter in combination with nonsustained atrial tachycardia.Of the 20 sites of pulmonary vein-left atrial conduction recovery mapped at the left-sided pulmonary vein,10 gap sites were at the left superior pulmonary vein(LSPV),7 gap sites at the left inferior pulmonary vein(LIPV),and 3 gap sites at the junction of left pulmonary vein,respectively.Of the 21 sites of pulmonary vein-left atrial conduction recovery mapped at the right-sided pulmonary vein,6 gap sites were at the right superior pulmonary vein(RSPV),13 at the right inferior pulmonary vein(RIPV),one at the carina site of right pulmonary vein,and one at the junction of right sided pulmonary vein,respectively.No non-pulmonary vein(non-PV)triggers were mapped except for one foci of left atrial posterior wall.Three patients underwent the linear ablation of cavotricuspid isthmus(CTI).After the redo procedure,11(45.8%)patients had the atrial fibrillation relapse,presenting with 8 cases of paroxysmal atrial fibrillation,one case of persistent atrial fibrillation,one case of nonsustained atrial tachycardia,and one case of atypical atrial flutter.The survival curve showed that the survival rate of freedom from atrial fibrillation recurrence were 74.2%at 12 months,59.3%at 24 months,and 53.4%at 30 months,respectively.Eleven patients with relapse after the redo procedure under the antiarrhythmic drug treatment had an obvious reduction of atrial fibrillation burden comparing with that after the cryoablation procedure.Conclusion:Pulmonary vein-left atrial conduction recovery was still the mainstay pathogenesis of atrial fibrillation recurrence after cryoballoon ablation of persistent atrial fibrillation,while the non-PV triggers were relatively scarce.Both the further reduction of atrial fibrillation burden and the maintenance time of sinus rhythm improved after the redo procedure.