Procedural Results
Procedural characteristics and outcomes are provided in Table
2 .
Of the 307 patients treated with amiodarone, 228 (74.3%) underwent CDV
during the pre-ablation period as part of a rhythm-control strategy.
This included 105 of the 124 amio-failure patients (84.5%) and 123 of
the 183 amio-success patients (67.2%). The average time from CDV to
subsequent ablation was the same (3months) in the amio-failure and
amio-success groups.
Patients underwent either RF (n=251; 81.8%) or cryoballoon (n=55;
18.2%) ablation. There was no difference in ablation modality used
between the amio-success and amio-failure patients. Of the 307 patients,
218 (74.3%) underwent index catheter ablation. Patients in the
amio-failure group presented either in AF (n=97; 78.2%) or in atrial
flutter (n=27; 21.8%). PVI-only was the dominant ablation strategy,
performed in 199/307(64.8%) patients. Extra-PVI ablation sites were
targeted in 108/307 patients (35.1%) and included roof line lesion sets
(26/307) and focal targets (10/307). Extra-PVI ablation was performed in
52 of the 183 amio-success cohort (28.4%) and 56 of the 124
amio-failure cohort (45.1%)
All 307 patients were followed for at least 12 months to survey for
arrhythmia recurrence after a 3m blanking period. AAD therapy was
discontinued in all patients during the blanking period. Off-drug
arrhythmia-free survival rates in the amio-success and amio-failure
cohorts were calculated using Kaplan-Meier survival curves
(Figure 2 ). The overall 1-year success rate was 57.7% and was
not different in the amio-success cohort (55.7%) versus the
amio-failure cohort (60.5%; p=0.54). Recurrent arrhythmias included
recurrent AF (30.3%), atrial flutter (9.1%), focal atrial tachycardia
(0.3%), or a combination of AF and flutter (2.6%) and did not differ
between amio-success and amio-failure cohorts.
Ablation success rates in the patients treated for PAF were similar in
the amio-success and amio-failure cohorts (55.2 versus 66.0%; p=0.27;Figure 3A ). Similarly, patients with persAF had similar
ablation outcomes between the two cohorts, with freedom from AF in
56.3% and 56.8% of patients in the amio-success and amio-failure
groups (p=0.91; Figure 3B ).
Complications occurred in 9 of the 307 patients studied (2.9%) and
included vascular access site issues (0.7%), aspiration pneumonia
(0.3%), pulmonary embolism (0.3%), and cardiac tamponade (1.6%)
(Table 3 ). There was no difference in complication rates
between the amio-success and amio-failure cohorts.