Clinical Significance of Inducibility Test of Atrial Fibrillation after Termination of Chronic, Persistent Atrial Fibrillation during Stepwise Approach

Background and Purpose: Atrial fibrillation (AF) termination has been used as the endpoint of Catheter ablation of longstanding persistent AF (LPAF). A value of an inducibility testing after achieving AF termination as predicting clinical outcome of Catheter ablation of AF is unclear. Methods: In 170 patients with LPAF (> 1 year) underwent stepwise approach (pulmonary vein isolation, multiple linear ablations, defragmentation, and bidirectional block of cavotricuspid isthmus), inducibility was tested by rapid atrial pacing after AF terminated. Results: Of 170 patients, induced AF (> 5 minutes) in 61 patients (group 1), induced atrial tachycardia (AT) (> 10 minutes) (group 2) in 72 and no induction of AF and AT (group 3) in 37. During 39 ±21 months of follow up, AF recurrence rate in group 1 (n=29, 48%) was similar to that in group 2 (n=34, 35%), however, higher than that in group 3 (n=10, 27%, p<0.05) Conclusion: Noninducibility of AF and AT after termination of LPAF during biatrial ablation led to a better outcome during the follow-up period.