February 18th, 2014
Trial Offers Little Support for Early Use of Radiofrequency Ablation in Atrial Fibrillation
A new trial offers little support for early use of radiofrequency ablation (RFA) to treat atrial fibrillation (AF). Current guidelines state that RFA may be indicated in patients with symptomatic paroxysmal AF after antiarrhythmic drug therapy has failed. Although earlier hopes have been dashed that RFA would prove to be a cure for AF, some experts have held out hope that RFA therapy would be better than drug therapy as initial treatment.
Some 127 patients with paroxysmal AF were randomized to antiarrhythmic therapy or RFA as initial treatment in the RAAFT-2 trial, published in JAMA. After 2 years, a documented symptomatic or asymptomatic atrial arrhythmia had occurred in 72.1% of patients in the drug group compared with 54.5% in the RFA group (HR 0.56, CI 0.35-0.90, p=0.02). But the difference in symptomatic arrhythmias alone was much smaller: 59% in the drug group compared with 47% in the RFA group (p=0.03). There were four cases of cardiac tamponade in the RFA group, a serious complication. After 1 year, there was a small improvement in quality of life in the overall patient population, but there was no significant difference between the groups. During the second year of follow-up, 43% of patients in the drug group crossed over and received RFA.
The authors note that although there were no deaths or strokes during the trial, the high rate of cardiac tamponade — despite the fact that all of the participating hospitals were highly experienced in RFA — was an indication that RFA “carries considerable risks that need to be discussed with the patient when offering it as a therapeutic alternative to patients who have not yet taken antiarrhythmic drugs.”
In an accompanying editorial, Hugh Calkins writes that RAAFT-2, along with other studies, “make it clear that symptomatic and asymptomatic recurrences of AF are not uncommon following AF ablation and that the efficacy of this procedure, even in optimal candidates, is modest.” The overall findings serve as “a powerful endorsement” of the current guidelines, which recommend RFA only after drug therapy has failed. However, he states, “patient preference and operator experience are important to consider.”
RAAFT-2 was sponsored by Biosense Webster. Other manufacturers of RFA devices for AF include Medtronic, Boston Scientific, and St. Jude Medical.