Hamilton, Canada: Catheter ablation (CA) is recommended as a second line therapy for AF patients in whom at least 1 antiarrhythmic drug (AAD) treatment has failed. RAAFT-2 study(1)  comparing radiofrequency catheter ablation with AADs showed that recurrence of atrial tachyarrhythmias was lower with CA. However there is increased risk of serious adverse events with ablation.

It is not clear whether CA is superior to AADs as first line therapy for AF. Wazni et al showed that CA as first line resulted in decreased AF recurrence (2). However a recent study demonstrated that CA was not superior to AADs in decreasing cumulative AF burden (3). This study sought to determine whether CA is superior to AADs as the first line treatment strategy for paroxysmal AF. This was a randomized multicenter study involving AAD naïve recurrent paroxysmal AF patients who were randomly assigned by computer in 1:1 fashion to either (i) CA or (ii) AADs.  After blanking period of 90 days, recurrence of arrhythmias in both groups were recorded. For patients in CA group, AADs and cardioversion during blanking period was allowed. AADs group patients who failed medical management were allowed to cross over to CA group after blanking period.  Primary efficacy outcome was time to first recurrence of any atrial tachyarrhythmia (AF/ atrial flutter/ atrial tachycardia) lasting more than 30 seconds. Serious adverse events in both groups were also recorded.

The study population included 127 patients with 66 patients in CA group and 61 patients in AAD group. Follow up duration was 24 months.  Recurrence of any atrial tachyarrhythmia was lower in CA group (54.5%, 36/66 patients) compared to AAD group (72.1%, 44/61patients) (HR 0.56, 95% CI, 0.35 - 0.90). Recurrence of symptomatic atrial tachycardia occurred less frequently in CA group (47%) compared to AAD group (59%)(HR 0.56, 95 % CI,  0.33 – 0.95). Symptomatic AF recurrence was lower in CA group (40.9%) to AAD group (57.4%)(HR 0.52, 95% CI 0.30 -0.89). Quality of life as assessed by visual analog scale improved significantly in CA group (p = 0.002) as well as AAD group (p=0.02).  There were no deaths or cerebro-vascular events in either group. Serious adverse events occurred in 9% patients undergoing ablation( cardiac tamponade in 6%) and in 5% of patients in AAD group (syncope, atrial flutter with 1:1 conduction).

This study showed that in AAD naïve AF patients, radiofrequency ablation resulted in decreased recurrence of atrial tachyarrhythmias. Symptomatic AF recurrence was lower with ablation. However in almost 50% patients undergoing ablation, there was recurrence of AF during follow up period of 24 months. There was improvement in quality of life with both ablation as well as AADs. In conclusion, the authors recommend the clinicians to discuss the risks and benefits of ablation and choose treatment option based on individual patient’s preferences.

References:

1. Morillo CA, Verma A, Connolly SJ et al. Radiofrequency ablation vs antiarrhythmic drugs as first-line treatment of paroxysmal atrial fibrillation (RAAFT-2): a randomized trial. JAMA : the journal of the American Medical Association 2014;311:692-700.

2. Wazni OM, Marrouche NF, Martin DO et al. Radiofrequency ablation vs antiarrhythmic drugs as first-line treatment of symptomatic atrial fibrillation: a randomized trial. JAMA : the journal of the American Medical Association 2005;293:2634-40.

3. Cosedis Nielsen J, Johannessen A, Raatikainen P et al. Radiofrequency ablation as initial therapy in paroxysmal atrial fibrillation. The New England journal of medicine 2012;367:1587-95.