Ablation Versus Drug Therapy for Atrial Fibrillation in Heart Failure: Results From the CABANA Trial

Abstract

Background: In patients with heart failure and atrial fibrillation (AF), several clinical trials have reported improved outcomes, including freedom from AF recurrence, quality of life, and survival, with catheter ablation. This article describes the treatment-related outcomes of the AF patients with heart failure enrolled in the CABANA trial (Catheter Ablation Versus Antiarrhythmic Drug Therapy for Atrial Fibrillation).

Methods: The CABANA trial randomized 2204 patients with AF who were ≥65 years old or <65 years old with ≥1 risk factor for stroke at 126 sites to ablation with pulmonary vein isolation or drug therapy including rate or rhythm control drugs. Of these, 778 (35%) had New York Heart Association class >II at baseline and form the subject of this article. The CABANA trial's primary end point was a composite of death, disabling stroke, serious bleeding, or cardiac arrest.

Results: Of the 778 patients with heart failure enrolled in CABANA, 378 were assigned to ablation and 400 to drug therapy. Ejection fraction at baseline was available for 571 patients (73.0%), and 9.3% of these had an ejection fraction <40%, whereas 11.7% had ejection fractions between 40% and 50%. In the intention-to-treat analysis, the ablation arm had a 36% relative reduction in the primary composite end point (hazard ratio, 0.64 [95% CI, 0.41-0.99]) and a 43% relative reduction in all-cause mortality (hazard ratio, 0.57 [95% CI, 0.33-0.96]) compared with drug therapy alone over a median follow-up of 48.5 months. AF recurrence was decreased with ablation (hazard ratio, 0.56 [95% CI, 0.42-0.74]). The adjusted mean difference for the AFEQT (Atrial Fibrillation Effect on Quality of Life) summary score averaged over the entire 60-month follow-up was 5.0 points, favoring the ablation arm (95% CI, 2.5-7.4 points), and the MAFSI (Mayo Atrial Fibrillation-Specific Symptom Inventory) frequency score difference was -2.0 points, favoring ablation (95% CI, -2.9 to -1.2).

Conclusions: In patients with AF enrolled in the CABANA trial who had clinically diagnosed stable heart failure at trial entry, catheter ablation produced clinically important improvements in survival, freedom from AF recurrence, and quality of life relative to drug therapy. These results, obtained in a cohort most of whom had preserved left ventricular function, require independent trial verification. Registration: URL: https://www.clinicaltrials.gov/ct2/show/NCT00911508; Unique identifier: NCT0091150.

Trial registration: ClinicalTrials.gov NCT00911508 NCT00911508 NCT00091150.

Keywords: antiarrhythmic drug; atrial fibrillation; catheter ablation; heart failure; paroxysmal atrial fibrillation; persistent atrial fibrillation; pulmonary vein.

Figures

Figure 1:

Primary Composite End Point (Death, Disabling Stroke, Serious Bleeding, or Cardiac Arrest) Kaplan-Meier Curves by Intention-to-Treat Among CABANA Heart Failure Patients

Figure 2:

All-Cause Mortality Kaplan-Meier Curves by Intention-to-Treat Among CABANA Heart Failure Patients

Figure 3:

Forest Plot of Pre-specified Subgroup Comparisons in CABANA Heart Failure Patients

Figure 4:

Cumulative Incidence Curves of First Recurrence of AF in the Post Blanking Period Among CABANA Heart Failure Patients Who Used the CABANA ECG Recording System

Figure 5:

Atrial Fibrillation Burden by Time and Randomization Assignment Among CABANA Heart Failure Patients Who Used the CABANA ECG Recording System

Figure 6:

Quality of Life Outcomes in CABANA Heart Failure Patients by MAFSI Scoring

Figure 6:

Quality of Life Outcomes in CABANA Heart Failure Patients by MAFSI Scoring