CABANA: Catheter ablation reduces AF recurrence through 5 years
At 5 years, patients with atrial fibrillation assigned catheter ablation had reduced recurrence of any AF compared with those assigned drug therapy, according to new data from the CABANA trial.
“These data support the finding of smaller trials that catheter ablation is superior to drug therapy to prevent recurrent AF,” Jeanne E. Poole, MD, professor of medicine in the division of cardiology and section head of electrophysiology at University of Washington in Seattle, told Healio. “CABANA was the largest trial conducted comparing a strategy of ablation to drug therapy, and across a broad group of patients with cardiovascular comorbidities. Our findings support catheter ablation as an important strategy which can be offered to patients with AF.”
Researchers analyzed data from 1,240 patients (median age, 68 years; 34% women; 43% with paroxysmal AF) from the CABANA trial who had AF and were assigned catheter ablation (n = 611) or drug therapy (n = 629).
The main results of the CABANA trial determined that catheter ablation conferred better outcomes compared with drug therapy in patients with AF in the on-treatment and per-protocol analyses, but not in the intention-to-treat analysis. As Healio previously reported, at a median follow-up of 4 years, for the primary endpoint of death, disabling stroke, serious bleeding or cardiac arrest, the difference between patients assigned ablation and those assigned drug therapy was not significant in the intention-to-treat analysis (HR = 0.86; 95% CI, 0.65-1.15), but favored ablation in both the on-treatment analysis (HR = 0.67; 95% CI, 0.5-0.89) and the per-protocol analysis (HR = 0.73; 95% CI, 0.54-0.99).
For the current study, all patients were observed for symptom-activated and 24-hour AF auto-detection with a proprietary ECG system. Researchers assessed AF burden every 6 months with 96-hour Holter monitoring.
The endpoint of interest — AF recurrence — was defined as any post-90-day blanking atrial tachyarrhythmias that lasted for 30 seconds or longer.
Patients assigned catheter ablation had significant reduction in asymptomatic AF (HR = 0.52; 95% CI, 0.45-0.6) and first symptomatic-only AF (HR = 0.49; 95% CI, 0.39-0.61) during 60 months of follow-up.
Both treatment groups had a baseline Holter AF burden of 48%. AF burden at 12 months was 6.3% in patients assigned catheter ablation and 14.4% in those assigned drug therapy. During 5 years of follow-up, the catheter ablation group had significantly less AF burden compared with the drug therapy group (14.7% vs. 20.8%; P < .001).
AF burden reduction in patients assigned catheter ablation did not differ by AF pattern at baseline.
“It is not clear what the best endpoint is to determine successful ablation, and it may vary amongst different patients,” Poole said in an interview. “We demonstrated positive results for catheter ablation when looking at AF burden. That finding is novel in that we included patients with persistent and longstanding persistent AF. Further studies exploring AF burden or other measures of recurrence such as AF density are needed to assess outcomes on quality of life, hospitalization or mortality.”
In a related editorial, Francis E. Marchlinski, MD, director of electrophysiology at the University of Pennsylvania Health system, director of the electrophysiology laboratory at the Hospital of the University of Pennsylvania and Richard T. and Angela Clark President’s Distinguished Professor at the University of Pennsylvania Perelman School of Medicine, and colleagues wrote, “The CABANA trial report on late AF recurrence confirms the clear benefit of catheter ablation vs. pharmacological therapy in preventing recurrent AF in patients with symptomatic AF, and is important in being one of the largest prospective studies to report on the benefit of catheter ablation on AF burden. Clearly, a burden assessment should be part of the reporting standards for assessing efficacy of therapy in preventing AF recurrence.”
For more information:
Jeanne E. Poole, MD, can be reached at email@example.com; Twitter: @jepoolemd.