Ablation of paroxysmal atrial fibrillation during coronary artery bypass grafting: 12 months' follow-up through implantable loop recorder

Abstract

Objectives: The study aimed to identify responders to atrial fibrillation (AF) ablation, through continuous subcutaneous monitoring in patients with paroxysmal atrial fibrillation (PAF), who underwent epicardial pulmonary vein isolation (PVI) concomitantly with coronary artery bypass grafting (CABG).

Methods: Seventy-two patients aged 61.6±4.7 years with PAF underwent epicardial PVI with bipolar radiofrequency during CABG. Conduction block was confirmed by pacing. At the end of the procedure, the implantable loop recorder (ILR) for continuous monitoring was implanted in all patients. Follow-up data were collected through the ILR telemetry. Patients with an AF burden (AF%)<0.5% were considered AF free (responders). Patients with AF%>0.5% were classified as non-responders. The AF episodes stored by the implanted device were visually inspected by the investigators to confirm the arrhythmia. The data were collected each month during 1-year follow-up.

Results: No procedure-related complications occurred either for ablation or for the monitoring device. At the first post-ablation follow-up (1 month) during the blanking period, 37 patients (51%) were AF free, that is, with AF%<0.5%. At the end of the blanking period (3rd follow-up), 44 (61%) patients were AF free. At 12 months' follow-up, 52 (72%) patients were AF free. Among 20 (28%) patients with AF recurrence, six (30%) patients were completely asymptomatic. There were no ischaemic strokes during the 1-year follow-up.

Conclusion: Concomitant AF ablation during CABG is effective in the treatment of AF, as assessed through 1 year of continuous monitoring. Use of subcutaneous monitors is safe and accurate for AF detection, clinically relevant in identifying responders and non-responders and managing the medical therapies accordingly.