Abstract 14381: Preliminary Results from the SPECULATE Randomized Study: Effect of Amiodarone on the Procedure Outcome in Long-Standing Persistent Atrial Fibrillation Undergoing Extended Pulmonary Vein Antrum Isolation
Introduction: Long standing persistent (LSP) atrial fibrillation (AF) is the most challenging type of AF to treat. Many centers perform ablation without discontinuation of Amiodarone (AM). Our study aims to investigate the role of AM in influencing the peri-procedural and follow-up outcomes in LSP-AF patients undergoing catheter ablation.
Methods: 105 patients (pts) treated with AM for LSP-AF and undergoing catheter ablation for AF have been enrolled in this prospective randomized multicenter study. Patients were randomized to AM discontinuation 4 to 6 months before ablation (group 1, n= 53) and to a control group (group 2, n = 52) where the ablation was performed without AM discontinuation. All patients underwent pulmonary vein antrum and posterior wall isolation, defragmentatation and extra PV triggers ablation. In group1 pts were not treated with AM during the blanking period (8 weeks post-ablation) while group 2 continued AM up to the end of the blanking period.
Results: Baseline clinical characteristics were not different between the 2 groups in term of sex, age, heart failure and comorbidities. During ablation, Group 2 had a higher number of pts with conversion of AF into an atrial tachyarrhythmia (AT) when compared to group 1 (42% vs 23%, p= .031), and a higher number of patients that converted into sinus rhythm (38 vs. 21%, p=.04). After high dosage of isoproterenol infusion, group 1 had a higher number of extra PVs triggers vs group 2 (72% vs. 42%, p= .002). Group 2 had a lower procedure, RF and fluoro time when compared to group 1 (2.7±1 vs 3.1± 1 h, 69 ± 4.3 min vs 87± 3.2 min and 64±14 min vs 85±18 min respectively). At the 6 months follow up, group 2 had a similar freedom from AF/AT, [38(72%) group 1 vs. 39 (75%) group 2 p= .702), but at the long term follow up of 24± 8 months, group 1 had a higher success rate off AADS [36(68%) vs. 27(52%), p=.046], and a lower rate of late recurrences [2 (4%) vs. 12(23)% p=.004]
Conclusions: The preliminary results of this study suggest that peri-procedural AM was associated with a higher organization rate and lower RF ablation. However, AM masks extra PV triggers, and it reduces the long term freedom from AF/AT predominantly by increasing the episodes of late recurrences.
- © 2011 by American Heart Association, Inc.