Catheter ablation was found to be superior to medical rate control (MRC) for improving left ventricular ejection fraction (LVEF) long term in patients with atrial fibrillation (AF) and systolic heart failure, according to a study published in the Journal of the American College of Cardiology: Clinical Electrophysiology.
Researchers sought to determine the long-term outcomes of restoring sinus rhythm with catheter ablation. In the Catheter Ablation Versus Medical Rate Control in Atrial Fibrillation and Heart Failure—An MRI-Guided Multicenter Randomized Controlled Trial, restoration of sinus rhythm with catheter ablation was found to significantly improve LVEF compared with MRC at 6 months in patients with persistent atrial fibrillation and otherwise unexplained systolic heart failure.
Patients were followed for 4 years during which they were assessed with echocardiogram and cardiac magnetic resonance. Catheter ablation involved pulmonary vein isolation and posterior left atrial wall isolation for 94% of participants in this cohort. Six months after enrollment, study participants were crossed over to catheter ablation. Arrhythmia burden was determined with implanted cardiac monitors or cardiac devices.
The analysis included 66 patients (mean age, 62±10 years; mean atrial fibrillation duration, 22±16 months; mean LVEF, 33±9%) who were randomly assigned 1:1 to catheter ablation or MRC treatment. Of 33 patients initially treated with MRC, 18 were crossed over to the catheter ablation group. At follow-up (mean, 4.0±0.9 years), atrial fibrillation had recurred in 27 patients (57%) in the catheter ablation group (mean burden, 10.6 ± 21.2% after 1.4±0.6 procedures). The absolute increase in LVEF was greater in the catheter ablation vs MRC group (16.4±13.3% vs 8.6±7.6%, respectively; P =.001).
Absence vs presence of ventricular late gadolinium enhancement (LGE) in participants in the catheter ablation group was associated with greater improvements in absolute LVEF (19±13% vs 10±11%, respectively; P =.04) and LVEF normalization (58% vs 18%, respectively; P =.008) at the follow-up.
“These findings demonstrate that the initial recovery of LV systolic function reported at 6 months in patients [randomly assigned] to catheter ablation was maintained at a mean follow-up of 4 years,” noted the study authors. “This was despite an increase in [atrial fibrillation] burden from 1.6±5% at 6 months to 10.6±21.2%.”
The investigators noted that this study is specific to patients with atrial fibrillation and otherwise unexplained cardiomyopathy without structural heart disease such as coronary artery disease or valvular heart disease. The study is also limited by its prospective observational design.
“Catheter ablation is superior to MRC in improving LVEF in the long term in patients with [atrial fibrillation] and systolic heart failure,” concluded the researchers. “The greatest improvements in systolic function occur in the absence of LGE on CMR imaging. Absence of structural heart disease or ventricular scar on CMR might help identify patients most likely to obtain long-term benefit from catheter ablation.”
Disclosures: Some of the study authors reported affiliations with medical technology companies. Please see the original reference for a full list of disclosures.
Sugumar H, Prabhu S, Costello B, et al. Catheter ablation versus medication in atrial fibrillation and systolic dysfunction: Late outcomes of CAMERA-MRI study [published online October 28, 2020]. J Am Coll Cardiol Clin Electrophysiol. doi: https://doi.org/10.1016/j.jacep.2020.08.019