Follow up
Antiarrhythmic medications were continued for a minimum of 3 months post
ablation and then weaned or ceased at the discretion of the treating
physician. Follow-up included clinical assessment and 12 lead ECG, at 3,
6 and 12 months and then ongoing follow-up as dictated by symptoms.
Patients with implantable cardiac devices capable of AF detection (dual
chamber device or implantable loop recorders) had device interrogation
performed at 3 months then yearly as a minimum. Patients without an
intracardiac device underwent 48 hours of ambulatory monitoring at
either 3 or 6 months follow-up with further monitoring dictated by
symptoms. Recurrence was defined as documented AF/AT >30
seconds with or without clinical symptoms, or recurrence requiring
pharmacological or interventional treatment, beyond a 3 month post
procedural blanking period. The ongoing use of antiarrhythmic drug
therapy was not counted as failure (since this was not part of a trial
with a protocol to stop them necessarily) but the success rate is
reported on and off antiarrhythmic drugs. Information was obtained from
the hospital data-registry and verified by assessment of hospital
medical records. Cardiac specific beta-blockers specifically used for
heart failure therapy were not classified as anti-arrhythmic agents.
Repeat ablation was offered to patients with symptomatic recurrence as
clinically indicated and was performed exclusively with RF ablation. The
ablation strategy involved PV re-isolation followed by mapping of
induced or spontaneous atrial tachycardias and further substrate-based
ablation at the operator discretion.