34 Use of general anaesthesia in catheter ablation of persistent af: improved outcome and cost effectiveness

Abstract

Introduction: The outcome of persistent AF ablation remains suboptimal and procedures may be long and painful. Little evidence is available on outcome for procedures under general anaesthetic (GA) compared to sedation. We performed a single-centre observational study to assess whether use of GA in persistent AF ablation improved outcome and was cost-effective. Methods: 292 patients undergoing first ablation procedures for persistent AF by radio-frequency point-by-point technique under conscious sedation (n = 220) or GA (n = 72) were followed. End points were freedom from recurrence of atrial arrhythmia and freedom from listing for repeat ablation at 18 months. Clinical assessments, 12 lead ECGs and 24 hr Holter monitors were obtained at baseline and at 3, 6, 12 and 18 months. Results: Baseline characteristics were not significantly different between groups. Freedom from atrial arrhythmia was higher in patients under GA rather than sedation (63.9% vs 42.3%, HR 1.87, 95% CI: 1.23-2.86, p = 0.002) (Fig A). There was no difference in procedure time and ablation time between groups. There were no complications resulting from use of GA; 5 cases under sedation were hindered by airway problems, agitation or pain. Significantly fewer GA patients were listed for repeat procedures (29.2% vs 42.7%, HR 1.62, 95% CI: 1.01-2.60, p = 0.044 (Fig B)). Of patients who had arrhythmia recurrence but did not undergo repeat ablation, main reasons were: only occasional recurrences of paroxysmal AF (PAF) (39%), feeling subjectively better despite continuing AF (20%), or low chance of success from further procedures (17%). Multivariate Cox regression analysis found a higher freedom from atrial arrhythmia with use of GA, as well as for decreasing age, normal LA size and decreasing time in AF pre-procedure. Decreasing age and use of GA increased freedom from listing for repeat ablation. A persistent AF procedure under GA in our institution is slightly more expensive than under sedation (£ 4406.68 vs £ 4115.15), but due to lower redo rates, the cost per patient after a maximum of two procedures is lower with GA, with an average saving of £ 178.88 per patient.(Figure presented) Conclusions: Using GA to perform persistent AF ablation is both clinically and financially effective. Patient immobility leads to improved accuracy of mapping and catheter stability, and optimizes lesion quality. Ablating during apnoea has been shown to improve contact force (1) and better outcomes have been demonstrated for PAF ablation under GA (2). However GA may be of particular use for persistent AF, where more extensive substrate ablation may be employed, procedures last longer and DCCV is often required. Limitations of the study are that patients were not randomised, and it would be useful to continuously monitor for asymptomatic episodes of paroxysmal AF and to gather Quality of Life information.