CAMERA-MRI II trial: Catheter Ablation versus Medical Rate Control of Atrial Fibrillation with Systolic Heart Failure and Myocardial Fibrosis – an MRI Guided Multi-Centre Randomised Controlled Clinical Trial

Interventional 1. Name: CAMERA-MRI II trial: Catheter Ablation versus Medical Rate Control of Atrial Fibrillation with Systolic Heart Failure and Myocardial Fibrosis – an MRI Guided Multi-Centre Randomised Controlled Clinical Trial. 2. Goal/Elements: Atrial fibrillation (AF) and heart failure (HF) are both emerging epidemics in developing countries with a significant influence upon morbidity and mortality. HF affects 1.5-2% of the Australian population as extrapolated by worldwide data, almost half of whom have ischaemic cardiomyopathy. AF and HF share common pathophysiological mechanisms, whereby AF may precipitate, worsen or be a consequence of HF. The restoration of sinus rhythm has the potential to improve LV function and clinical outcomes in patients with HF and concurrent AF. Catheter ablation (CA) has established itself as superior to medical therapy, particularly in patients with HF, with an acceptable risk profile, albeit with a lower procedural efficacy compared to patients without HF. Although, early clinical trials have demonstrated LVEF improved irrespective of HF aetiology, other studies suggest pre-existing structural heart disease, such as prior myocardial infarction predicts reduced procedural efficacy and poor recovery of left ventricular (LV) systolic function. The CAMERA-MRI trial specifically focused on patients with AF and idiopathic or otherwise unexplained cardiomyopathy and showed that MRI-detected myocardial fibrosis could predict the extent of ventricular recovery following CA. The recent CASTLE-AF study reported improved mortality and unplanned HF hospitalisation following CA in all aetiologies of HF with concurrent AF, including ischaemic cardiomyopathy, however the impact of myocardial fibrosis or heart failure aetiology was not specifically evaluated. This randomised clinical trial will evaluate the role of cardiac MRI (CMR) in all patients with AF and heart failure, including those with ischaemic cardiomyopathy or known contributing myocardial fibrosis on LV recovery and clinical outcomes at 12 months. 3. Materials: This trial incorporates standard practice for patients with AF and HF. All patients being considered for this trial will be invited to meet the study investigators to assess study eligibility and they will be provided with written information regarding AF and HF management options available as per standard routine care. If they meet eligibility based on the study criteria, they will then be offered enrolment in our trial. If they choose to, addition written information will be provided at that point about the intervention (catheter ablation). All trial patients will be followed up closely at 3, 6 and 12 months after the intervention. Participants randomised to the medical rate control group will be followed up at the same time intervals. 4. Catheter Ablation Procedure: Standard pulmonary vein isolation will be performed in all patients randomised to the CA group by an Electrophysiologist. Additional ablation may be performed at the operator's discretion. This is a minimally invasive procedure performed under general anaesthesia in the cardiac catheter laboratory. The procedure is performed via femoral venous access (ultrasound guidance) with catheters advanced into the heart. The pulmonary veins in the left atrium are targeted with either radio frequency ablation (RFA) or cryoablation using special catheters that can deliver energy to the atrial tissue. At the end of the procedure, all sheaths and catheters are removed from body. 5. Standard care will be provided by the treating cardiologist or electrophysiologists, regardless of whether the patient chooses to participate in the trial. 6. Mode of Delivery: Patient care, treatments and follow up will be provided directly through the participating institutions. 7. Location/s: The participating sites include recruitment and procedural sites: the Alfred Hospital, the Royal Melbourne Hospital, University Hospital Geelong, Monash Medical Centre, Westmead Hospital, Mulgrave Private Hospital, the Epworth Hospital and Cabrini Hospital. Sunshine Hospital will be a recruitment site. Patients can be referred from non-participating institutions to any of the participating recruitment sites. 8. Intervention: Catheter ablation will be performed once as part of the trial. Subsequent ablation may be considered based on the patient's individual clinical circumstances, clinical indication and treating specialist recommendation. The procedure duration is approximately 2 hours. 9. Tailoring: The ablation strategy will be at the operator's discretion. Continuation of anti-arrhythmic medications beyond the ablation procedure will be at the operator's discretion based on the patient's clinical circumstance. 10. Modification: Any intervention or modification to the intended intervention that is deemed necessary for the benefit of the patient will be undertaken as needed.