057 A randomised controlled trial of catheter ablation vs medical treatment of atrial fibrillation in heart failure (the CAMTAF trial)

Introduction

Although atrial fibrillation (AF) has deleterious effects in patients with heart failure (HF), rhythm control using medication has limited efficacy. Catheter ablation (CA) of AF is effective in restoring sinus rhythm, raising the question: if it can be shown to be safe and effective in HF patients, might it improve left ventricular (LV) function and HF symptoms? We sought to compare the impact of a CA strategy to a medical rate control strategy (MED) in patients with persistent AF and HF.

Methods

Patients with persistent AF, symptomatic HF, and a LV ejection fraction (EF) <50%, were randomised to CA or MED. HF medication and anticoagulation were optimised prior to baseline observations. For those with recurrent AF in the CA group, a repeat procedure was performed at the end of the 3-month blanking period and follow-up re-started. The primary end-point was the difference in LV EF between groups on echocardiography at 6 months. Echocardiographic data were anonymised and core reported by a blinded collaborating centre. Secondary end-points included difference in NYHA class, Minnesota living with heart failure questionnaire score, and peak oxygen consumption at 6 months.

Results

55 patients were randomised, but five were excluded (LV function normalised during optimisation of medications prior to baseline tests in 2, and 3 withdrew un-happy with their treatment allocation). Patients were 58±11 years and 96% were male. Baseline LV EF was 31±10% in the CA group and 33±9% in the MED group. NYHA class was 2.5±0.5 in both groups. Patients underwent 1.6±0.7 procedures. There were two complications: (1) stroke and 1 tamponade. In the CA group 1 patient withdrew after a procedural stroke, and in the MED group 1 patient died. In total 21 of 24 in the MED group and 24 of 26 in the CA group had reached 6-months follow-up and were included in this analysis of the primary end-point. Freedom from AF was achieved in 21/24 (88%) off antiarrhythmic drugs in the CA group, whereas all those in the MED group remained in AF. LV EF in the CA group at 6 months was 39±10% compared to 32±13% in the MED group (p<0.05). NYHA class was also significantly lower in the CA group at 6 months (1.7±0.8 compared to 2.3±0.6 in the medical group; p<0.05). CA was associated with better peak oxygen consumption (22.4±6.3 ml/kg/min vs 18.6±6.0 ml/kg/min, p=0.053) and Minnesota living with heart failure questionnaire score (24±23 vs 48±25, p=0.002) compared to the MED group.

Conclusions

CA is effective in restoring sinus rhythm in the majority of patients with persistent AF. A CA strategy for patients with AF and HF is associated with improved LV function and heart failure symptoms compared to medical treatment alone.