Long-Term Clinical Comparison of Procedural End Points After Pulmonary Vein Isolation in Paroxysmal Atrial Fibrillation

Abstract

BACKGROUND:Pulmonary vein isolation (PVI) is effective for maintenance of sinus rhythm in 50% to 75% of patients with paroxysmal atrial fibrillation, and it is not uncommon for patients to require additional ablation after PVI. We prospectively evaluated the relative effectiveness of 2 post-PVI ablation strategies in paroxysmal atrial fibrillation. METHODS AND RESULTS:A total of 500 patients (mean age, 55.7±11.0 years; 74.6% male) were randomly assigned to undergo ablation by 2 different strategies after PVI: (1) elimination of non-PV triggers (group A, n=250) or (2) stepwise substrate modification including complex fractionated atrial electrogram or linear ablation until noninducibility of atrial tachyarrhythmia was achieved (group B, n=250). During a median follow-up of 26.0 months, 75 (32.2%) patients experienced at least 1 episode of recurrent atrial tachyarrhythmia after the single procedure in group A compared with 105 (43.8%) patients in group B (P value in log-rank test of Kaplan-Meier analysis: 0.012). Competing risk analysis showed that the cumulative incidence of atrial tachycardia was significantly higher in group B compared with group A (P=0.007). With the exception of total ablation time, there were no significant differences in fluoroscopic time or procedure-related complications between the 2 groups.CONCLUSIONS: Elimination of triggers as an end point of ablation in patients with paroxysmal atrial fibrillation decreased long-term recurrence of atrial tachyarrhythmia compared with a noninducibility approach achieved by additional empirical ablation. The post-PVI trigger test is thus a better end point of ablation for paroxysmal atrial fibrillation.

Role of inducibility and its dynamic change in the outcome of catheter ablation of atrial fibrillation: a single center prospective study

“…Leong‐Sit et al 16 investigated 144 patients with paroxysmal or persistent AF and found no statistical difference in recurrence rate regarding inducibility. The same results were reported from Santangeli et al 17 and Otsuka et al 20 Moreover, in a recent larger study from Lee et al 21 with 500 patients, inducibility was proven to be inferior to non‐PV triggers elimination in long‐term follow‐ups. Kawai et al 23 concentrated on patients with persistent AF and showed no benefit from non‐inducibility.…”

“…On the other hand, recent studies have shown opposite results and have questioned the role of inducibility as an endpoint criterium for the success of AF ablation 16,17,20–23 . Leong‐Sit et al 16 investigated 144 patients with paroxysmal or persistent AF and found no statistical difference in recurrence rate regarding inducibility.…”

“…Huang et al 27 and Kumar et al 28 demonstrated that repeated stimulation protocols can induce AF even in patients with other forms of supraventricular tachycardias, thus making inducibility a probabilistic phenomenon. Many studies tried to compare pacing with isoproterenol induction and thus compared two different mechanisms for AF: Pacing protocols test the sustainability of AF when the atria are stimulated in high‐frequency trains whereas isoproterenol can reveal dormant focal triggers 15,21 …”

“…Especially among these patients, AF/AT inducibility and change in inducibility status could be used as a procedural endpoint. Older observational studies were controversial concerning any prognostic value of inducibility as a procedural endpoint 6–11,15–23 . We conducted a prospective study of AF/AT inducibility with different protocols before and after the ablation, as well as different stimulation locations and assessed the role of it in predicting long‐term AF freedom.…”

“…Older observational studies were controversial concerning any prognostic value of inducibility as a procedural endpoint. [6][7][8][9][10][11][15][16][17][18][19][20][21][22][23] We conducted a prospective study of AF/AT inducibility with different protocols before and after the ablation, as well as different stimulation locations and assessed the role of it in predicting long-term AF freedom.…”