Relationship Between Amiodarone Response prior to Ablation and One-Year
Outcomes of Catheter Ablation for Atrial Fibrillation
Abstract
Background: Catheter ablation for atrial fibrillation (AF) is a
common therapeutic strategy for patients with either paroxysmal or
persistent AF, but long-term ablation success rates are imperfect.
Maintenance of sinus rhythm immediately prior to ablation with
anti-arrhythmic drug (AAD) therapy has been associated with improved
outcomes in patients undergoing ablation. Amiodarone has superior
efficacy relative to other AADs. Whether failure of amiodarone to
maintain sinus rhythm prior to ablation for either paroxysmal or
persistent AF is associated with poor outcomes is unknown.
Methods: A total of 307 patients who received amiodarone in a
one-year window before undergoing catheter ablation for AF were
included. Patients were divided into amiodarone success (n=183) and
amiodarone failure (n=124) groups based on the response to pre-ablation
amiodarone treatment. Analysis of procedural outcomes as a function of
response to amiodarone therapy was performed. Patients were followed for
at least 12 months post-ablation to assess outcomes (adverse events and
arrhythmia recurrence). Procedural success was defined by the absence of
documented arrhythmia (>30s) without any anti-arrhythmic
agents beyond a 90d blanking period. Results: Following
ablation for either paroxysmal or persistent AF, freedom from any
recurrent atrial arrhythmia at 1y was 57.7% for the entire cohort.
One-year freedom from recurrent arrhythmia in the amiodarone success
group was comparable to that in the amiodarone failure group (55.7% vs
60.5%; p=0.54). Success rates following ablation did not vary by the
response to amiodarone when analyzed for paroxysmal or persistent AF
subgroups. Conclusion: Failure to restore and maintain sinus
rhythm with amiodarone prior to ablation for either paroxysmal or
persistent AF is not a predictor of ablation procedural failure.
Amiodarone failure alone should not deter practitioners from considering
ablation therapy for patients with AF.