Efficacy Analysis Of Ethanol Infusion In The Ligament Of Marshall Combined With Catheter Ablation In The Treatment Of Persistentatrial Fibrillation

Objective:In patients with persistent atrial fibrillation,incomplete and non-transmural linear ablation can lead to an increase in iatrogenic atrial flutter and atrial tachycardia,which reduces the success rate of ablation for persistent atrial fibrillation.Ablation of the mitral isthmus is challenging.The reasons for the difficulty of mitral isthmus ablation include:Mitral isthmus has great anatomical variability and uneven thickness.The tissue thickness of the thickest part usually exceeds the depth of catheter ablation,resulting in the difficulty of mitral isthmus ablation to penetrate the wall.There are circumflex artery branches in the mitral isthmus,and the blood flow will take away part of the ablation energy.The most important cause is the presence of Marshall ligament(LOM).The LOM is located posterolateral of the left atrium,bridging the coronary sinus muscle sleeve to the left atrial epicardium,which can connect the ablation line of endocardium blocked.The purpose of this study was to investigate the safety and efficacy of LOM alcohol ablation combined with catheter ablation in the treatment of persistent atrial fibrillation.Methods:We reviewed patients with persistent atrial fibrillation who underwent catheter ablation at the Second Affiliated Hospital of Nanchang University between January2020 and March 2021.The patients were stratified into group EIVOM(pulmonary vein isolation,linear ablation,EIVOM),group RF(pulmonary vein isolation,linear ablation).Propensity‐score analysis was used to adjust for 11 confounding factors including age,sex,hypertension,diabetes mellitus,coronary artery disease,chronic heart failure,old ischemic stroke,CHA2DS2‐VASc score,long‐standing persistent AF,left atrial diameter,left ventricular ejection fraction(EIVOM:RF=1:2).Long-term efficacy was assessed using a resting surface 12-lead electrocardiogram and dynamic electrocardiogram.At 3、6 and 12 months after ablation,dynamic electrocardiogram(From 1 to 7 days)monitoring was performed regularly.Follow-up should be performed at any time if the patient develops symptoms of tachyarrhythmia.End points included atrial fibrillation recurrence and mitral isthmus block during operation.Recurrence of atrial fibrillation was defined as an episode of rapid atrial arrhythmia(Including atrial fibrillation,atrial flutter,atrial tachycardia)lasting more than 30 seconds 3 months after ablation(blank period).Results:After matching propensity scores,there were 40 patients(63.4 ± 8.8 years,23males)in the group EIVOM and 76 patients(61.6 ± 9.7 years,40 males)in the group RF.Mitral isthmus block was achieved in 40 patients(100%)in group EIVOM and53 patients(69.7%)in group RF(P < 0.001).at 12 months of follow-up,6 patients(15%)in the EIVOM group and 25 patients(32.9%)in the RF group had recurrent atrial fibrillation(P=0.038).In cox regression,EIVOM was associated with a lower recurrence rate(HR=0.4;95% CI,0.1‐0.9;P = 0.04).In the group EIVOM,coronary sinus dissection was observed in 1 patient and inguinal hematoma in 2patients.In the group RF,inguinal hematoma was observed in 5 patients.No serious complications such as death,stroke,atrial esophageal fistula,or pericardial effusion were observed in the study population.here were no changes in electrocardiogram related to circumflex artery injury.Conclusions:In patients with persistent atrial fibrillation,VOM alcohol ablation combined with catheter ablation can significantly improve the rate of bidirectional mitral isthmus occlusion.VOM alcohol ablation combined with catheter ablation can improve the ablation success rate of persistent atrial fibrillation,which is worthy of clinical promotion and application.