Rhythm Control - Catheter Ablation With or Without Anti-arrhythmic Drug Control of Maintaining Sinus Rhythm Versus Rate Control With Medical Therapy and/or Atrio-ventricular Junction Ablation and Pacemaker Treatment for Atrial Fibrillation

Heart Failure, Atrial Fibrillation

Heart Failure, Atrial Fibrillation, Catheter Ablation, Anti-arrhythmic Medications, Cardiovascular Mortality

Atrial fibrillation and heart failure are two common heart conditions that are associated with an increase in death and suffering. When both of these two conditions occur in a patient the patient's prognosis is poor. These patients have poor life quality and are frequently admitted to the hospital. The treatment of atrial fibrillation in heart failure patients is extremely challenging. Two options for managing the atrial fibrillation are permitting the atrial fibrillation to continue but controlling the heart rate, or to convert the atrial fibrillation rhythm back to normal and try to maintain the heart in sinus rhythm. Until now, the method to keep the patient in normal sinus rhythm is with antiarrhythmic drugs. Studies using antiarrhythmic drugs to control the rhythm failed to show any survival benefit when compared with permitting the patient to be in atrial fibrillation. In the last few years, new development in techniques and technologies now enable catheter ablation (cauterization of tissue in the heart with a catheter) to be a successful treatment in abolishing atrial fibrillation and that this approach is better than antiarrhythmic drug to control the rhythm. However, there has not been any long-term study to determine whether catheter ablation to abolish atrial fibrillation in heart failure patients would reduce mortality or admissions for heart failure. This study is to compare the effect of catheter ablation-based atrial fibrillation rhythm control to rate control in patients with heart failure and high burden atrial fibrillation on the composite endpoint of all-cause mortality and heart failure events defined as an admission to a healthcare facility for \> 24 hours or clinically significant worsening heart failure leading to an intervention (defined as treatment in an emergency department, a same-day access clinic, or an infusion centre) or unscheduled visits to a healthcare provider for administration of an intravenous diuretic and an increase in chronic heart failure therapy. This study may have a dramatic impact on the way the investigators manage these patients with atrial fibrillation and heart failure and may improve the outlook and well being of these patients.

Substudy\_ In a subset of patients, following informed consent, additional data collection will include annual NT-proBNP/BNP measurements, Echocardiogram baseline and annually and 14 Day ECG Continuous Monitoring at six month intervals. Updated June 2024: Additional analysis will be completed using the winratio analysis for the hierarchical primary outcome of: 1. All-cause mortality (time to event) 2. Heart Failure Events (number of events per year) defined as an admission to a healthcare facility for \> 24 hours or clinically significant worsening heart failure leading to an intervention (defined as treatment in an emergency department, a same-day access clinic, or an infusion centre) or unscheduled visits to a healthcare provider for administration of an intravenous diuretic as accepted by FDA, and an increase in chronic heart failure therapy 3. Minnesota Living with Heart Failure Questionnaire (change from baseline to 12-month) 4. Six Minute Hall Walk Test (change from baseline to 12-month)

Brazil, Canada, Sweden, Taiwan