Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Clinical Trials / Outcomes D-PO03 - Poster Session III (ID 48) Poster

D-PO03-173 - The Relationship Between The Required Energy For Internal Cardioversion And Recurrence After Catheter Ablation Of Non-paroxysmal Atrial Fibrillation (ID 351)


Background: The minimal energy requirement (Emin) for electrical cardioversion (ECV) theoretically is related to the critical mass for sustaining atrial fibrillation (AF).
Objective: To investigate the above setting, we analyzed the association with the Emin for internal ECV and the outcome of catheter ablation of non-paroxysmal AF.
Methods: We studied 364 consecutive patients with non-paroxysmal AF undergoing first-time radiofrequency catheter ablation (age, 68±8.9 years old; male, 74.7%; persistent AF [PEF], 73.1%). Before the pulmonary vein isolation, internal ECV began with 5 J using a purpose-built cardioversion catheter in which direct current was delivered between the right atrium and coronary sinus, and was serially increased to 10, 20, and 30 J until sinus rhythm was achieved to determine the Emin.
Results: During a 1.8±1.1 year-follow-up, 81 patients had AF recurrences. Patients with an Emin ≥ 20J more likely had an AF recurrence than those with an Emin <20J. This held true in patients with long standing PEF (LSPEF) but not in those with PEF (Figures). A multivariate analysis disclosed that an Emin ≥ 20J (HR 1.59, 95%CI 1.02-2.46, p=0.040) and LSPEF (HR 1.89, 95%CI 1.18-3.03, p=0.009) were significant predictors of AF recurrence.
Conclusion: A high internal ECV Emin may indicate being at high risk for a post-catheter ablation AF recurrence in patients with LSPEF but not in those with PEF. The results support the theory that the internal ECV Emin reflects the critical mass for sustaining AF since the substrate plays a greater role in AF recurrence in patients with LSPEF than PEF.