Among younger patients with treatment-naive paroxysmal atrial fibrillation, radiofrequency ablation modestly lowered the rate of recurrent atrial tachyarrhythmia during 2 years of follow-up, compared with medical therapy, according to a report published online Feb. 18 in JAMA.
"Ablation extends the time free of both symptomatic and asymptomatic AF and significantly reduced the recurrence of repeated episodes, potentially having an effect on AF progression." However, recurrent AF was documented in nearly half of the patients who underwent ablation, and quality of life was improved to the same degree in both groups, said Dr. Carlos A. Morillo of the Population Health Research Institute, McMaster University, Hamilton (Ont.), and his associates.
The investigators conducted the second Radiofrequency Ablation vs. Antiarrhythmic Drugs as First-Line Therapy of Atrial Fibrillation (RAAFT-2) clinical trial to examine whether ablation is superior to drugs as first-line therapy for patients with treatment-naive paroxysmal AF. Over the course of 4 years, the 127 study subjects (mean age, 55 years) were treated and followed at 16 medical centers in North America and Europe.
These participants were randomly assigned to undergo ablation (66 patients) or receive antiarrhythmic medications (61 patients) and were monitored by telephone biweekly, as well as every time they experienced symptoms, for 2 years.
Recurrence of any atrial tachyarrhythmia lasting longer than 30 seconds was documented in 36 patients in the ablation group (54.5%), compared with 44 in the medication group (72.1%). In addition, asymptomatic AF occurred in 6 patients in the ablation group (9%), compared with 11 in the medication group (18%).
Symptomatic recurrence of AF, atrial flutter, or atrial tachyarrhythmia occurred in 31 patients in the ablation group (47%), compared with 36 in the medication group (59%). And the rate of multiple recurrences of symptomatic or asymptomatic atrial tachyarrhythmia also favored ablation over medication, Dr. Morillo and his associates said (JAMA 2014 Feb. 18;311:692-9 [doi:10.1001/jama.2014.467]).
At baseline, quality of life was moderately impaired in both groups as measured by the EQ-5D. In both groups, it improved to roughly the same degree and normalized at 1 year.
The most frequent major complication in the ablation group was cardiac tamponade, which developed in 6% of patients. Severe pulmonary vein stenosis developed in 1.5%, and bradycardia requiring placement of a permanent pacemaker developed in 1.5%. "This highlights the fact that ablation 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," the investigators noted.
They added that their study sample was relatively small and the treatment effect, though statistically significant, "may be clinically modest." Moreover, "the risks of ablation were not negligible," Dr. Morillo and his colleagues said.