Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Ablation Techniques D-PO02 - Poster Session II (ID 47) Poster

D-PO02-182 - Best Ablation Strategy In Patients Presenting With Atrial Flutter Following Successful Isolation Of Pulmonary Veins For Atrial Fibrillation (ID 1049)


Background: Left sided atrial flutter (LAFL) accounts for a substantial proportion of symptomatic recurrences after AF ablation. Post-ablation AFL is often incessant and associated with rapid ventricular response that is difficult to control with drugs.
Objective: To evaluate the efficacy of different ablation strategies in patients presenting with LAFL following successful pulmonary vein isolation (PVI) for AF.
Methods: Consecutive patients undergoing repeat catheter ablation for atrial flutter following effective PVI, were included in the study. All of these patients received PVI plus isolation of left atrial posterior wall and superior vena cava at the earlier procedure. LAFL circuit was documented by direct mapping with a 3D electroanatomic mapping system. Based on the ablation strategy patients were classified into group 1: Flutter ablation only and group 2: non-PV trigger ablation. Non-PV sites included coronary sinus (CS), inter-atrial septum, mitral valve annulus and left atrial appendage (LAA). In case of LAA and CS triggers, electrical isolation of the structures was performed. In group 1, noninducibility of targeted flutter morphology was confirmed with pacing at 20mA. Bidirectional conduction block was ascertained in all group 1 patients. All patients were followed up for arrhythmia for up to 2 years.
Results: No PV reconnection was detected in the study population. A total of 93 received flutter ablation only and 833 patients underwent non-PV trigger ablation.
More patients in Group 1 were female (55.9% vs 34.3%, p<0.001) ,had higher LV ejection fraction (mean 59.9 vs 54.8, p<0.001) and non-obese(mean 26.5 vs. 30.4, p<0.001). Age and other clinical characteristics were similar between the groups. At 18.6 ± 8 months, 15/93 (16%) from the group 1 were in sinus rhythm on-antiarrhythmic drugs whereas 638/833 (76.6%) from group 2 remained arrhythmia-free off-drugs (log rank p <0.001). In the multivariate analysis, after adjusting for clinically relevant covariates, flutter-ablation only was associated with significantly high risk for recurrence (HR: 6.43 (4.88-8.46), p-value <0.001).
Conclusion: In AFL following successful PVI, ablation of non-PV triggers was associated with significantly higher success rate compared to flutter ablation alone.