• Arrhythmias
• Interventional Techniques & Devices
• Cardiology Clinical Trials

• Cardiology & Cardiovascular Medicine
• Arrhythmias
• Interventional Techniques & Devices
• Cardiology Clinical Trials

Radiofrequency ablation (RFA) has emerged as an effective therapy for patients with paroxysmal atrial fibrillation (PAF) [Stabile G et al. Eur Heart J 2006], and at least 1 international consensus document concludes that ablation is an acceptable first option for patients with symptomatic PAF [Caulkins H et al. Europace 2012]. However, limited data are available comparing this technology with antiarrhythmic drug (AAD) therapy as first-line treatment for patients with PAF.

Jens Cosedis Nielsen, MD, Aarhus University Hospital, Skejby, Denmark, reported 24-month outcomes from the Medical Antiarrhythmic Treatment or Radiofrequency Ablation in Paroxysmal Atrial Fibrillation trial [MANTRA-PAF; Cosedis Nielsen J et al. N Engl J Med 2012]. The trial was designed to compare the efficacy of RFA with AADs in relatively young male symptomatic patients [Jons C et al. Europace 2009]. Eligibility criteria included ≥2 symptomatic episodes of AF with an indication for rhythm control within the preceding 6 months and no episodes of AF lasting >7 days. Baseline characteristics of the patients are described in Table 1.

A total of 294 patients were randomly assigned to undergo first-line treatment of catheter ablation (n=146) or medical therapy (n=148) [Cosedis Nielsen J et al. N Engl J Med 2012]. The preferred medical agents were flecainide or propafenone. If these 2 were contraindicated, patients could receive either amiodarone or sotalol. Follow-up included 7-day Holter monitoring at 3, 6, 12, 18, and 24 months. If drug therapy failed, patients were offered supplementary RFA as clinically indicated. The primary end points were the cumulative burden of AF (the percentage of time spent in AF) and the AF burden at each 7-day Holter recording; follow-up was completed in May 2011.

Dr. Nielsen reported that at 2 years, there was no significant cumulative difference between the 2 treatment groups in either cumulative AF burden or that at 7-day Holter monitoring. In both groups, the burden of AF was significantly lower at each follow-up than at baseline (p<0.001 for all comparisons). The only significant difference reduction in AF burden was noted in the ablation group at 24 months (p=0.007). Twenty patients in the RFA group and 16 patients in the AAD group suffered adverse events, which was not significantly different (p=0.45; Table 2).

Dr. Nielsen then turned to a comparison of the costs for each procedure. Data from MANTRA-PAF were analyzed to determine the cost-effectiveness of RFA compared with medical therapy as a first-line treatment for PAF [Aronsson A et al. Eur Heart J 2013]. While RFA was associated with some clinical improvement in the overall population, the benefits occurred primarily in the youngest quartile of patients. RFA was almost cost neutral in patients aged ≤50 years as compared with patients aged >50 years. For example, the incremental cost-effectiveness ratio for a 45-year-old patient was €3434 per quality-adjusted life year (QALY) gained, compared with €108,937 per QALY gained for patients aged >65 years.

Dr. Nielsen closed his presentation with some caveats. It may be that no differences were noted in the 2 groups because RFA techniques have improved since the study began. Additionally, it is important to remember that RFA should be used only for patients with symptomatic AF and that RFA does carry a risk of serious adverse events. Perhaps most important is that the relatively young patients in this trial do not represent the true AF cohort in the population and that the results should not be extrapolated to the broader (older) population with AF.

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