ATTEST: Radiofrequency ablation superior to antiarrhythmic drugs for AF progression

PARIS — Early radiofrequency ablation was superior to antiarrhythmic drugs to delay the progression to persistent atrial fibrillation among patients with drug-refractory paroxysmal AF, according to 3-year data from the ATTEST trial presented at the European Society of Cardiology Congress.
“To date, catheter ablation has been primarily indicated for second-line, symptomatic treatment of paroxysmal AF after failure of at least one antiarrhythmic drug,” Karl-Heinz Kuck, MD, head of the department of cardiology at Asklepios Klinik St. Georg in Hamburg, Germany, said during the presentation. “The ATTEST results, if confirmed by further studies, may introduce a new indication for catheter ablation in patients with paroxysmal AF.”
Researchers analyzed data from 255 patients (mean age, 68 years; 42% men) older than 60 years who have had paroxysmal AF for at least 2 years, had at least two AF episodes in the past 6 months, have failed with one to two antiarrhythmic drugs or rate control drugs and have a HATCH score (hypertension, aged at least 75 years, transient ischemic attack or stroke, chronic obstructive pulmonary disease, and HF) between 1 and 4.
Patients were assigned radiofrequency ablation (n = 128), which included pulmonary vein isolation with 3D electroanatomic mapping, or antiarrhythmic drugs (n = 127), which were administered according to current guidelines at the investigators’ discretion.
Follow-up visits were performed at 3 months, 6 months, 1 year, 2 years and 3 years. The primary endpoint was the progression to persistent AF or atrial tachycardia at 3 years, which was defined as an event lasting longer than 7 consecutive days or requiring termination with cardioversion after 48 hours.
The study was terminated in February 2018 due to slow enrollment, which occurred approximately 1 year after the second interim analysis.
Crossovers from the antiarrhythmic drug group to the radiofrequency ablation group occurred in 12.2% of patients. Three-year follow-up data were available for 46 patients assigned radiofrequency ablation and 52 patients assigned antiarrhythmic drugs.
At 3 years, the rate of persistent AF or atrial tachycardia was lower among patients assigned radiofrequency ablation compared with those assigned antiarrhythmic drugs (2.4% vs. 17.5%; P = .0009). The radiofrequency group was approximately 10 times less likely to develop persistent AF compared with the antiarrhythmic drug group (HR = 0.114).
When the 2017 definition of persistent AF from the Heart Rhythm Society was considered, there was no progression among patients assigned radiofrequency ablation compared with 13 patients assigned antiarrhythmic drugs. This resulted in a 3-year Kaplan-Meier rate estimate of 17.5% for patients in the antiarrhythmic drug group (P < .001).
Results were similar in the per-protocol population, as 20.6% of patients in the antiarrhythmic drug group progressed to persistent AF or atrial tachycardia compared with 2.2% of those in the radiofrequency ablation group (P < .0001).
The delay in disease progression by catheter ablation was homogenous in prespecified subgroup analyses except among patients with hyperlipidemia and diabetes. Patients who were older than 65 years were approximately four times more likely to progress to persistent AF or atrial tachycardia regardless of treatment compared with those younger than 65 years.
In the intention-to-treat population, the rate of recurrent AF or atrial tachycardia among patients assigned radiofrequency ablation was lower at 3 years compared with those assigned antiarrhythmic drugs (57.1% vs. 84.7%; P = .0002).
The repeat ablation rate was 17.1% at 3 years, with 14 patients requiring two or more ablations during this period. – by Darlene Dobkowski
Reference:
Kuck K-H. Late-Breaking Science in Atrial Fibrillation 1. Presented at: European Society of Cardiology Congress; Aug. 31-Sept. 4, 2019; Paris.
Disclosures: The trial was sponsored by Biosense Webster. Kuck reports he is a consultant for Abbott, Biosense Webster, Boston Scientific, Edwards Lifesciences and Medtronic.