Dr. Burak Kardeşler

Study Title: Cryoballoon vs. Radiofrequency Ablation for AF in Heart Failure Patients: CRABL-HF Trial

Congress: ESC 2024

Introduction:
Catheter ablation for atrial fibrillation (AF) has increasingly been performed in patients with heart failure in recent times. However, it has recently been emphasized that heart failure is associated with an increased risk of procedural complications and mortality in AF ablation.

Objective:
There is very limited data on the differences in efficacy and safety between cryoballoon (CB) and radiofrequency (RF) ablation for AF in heart failure patients. The CRABL-HF study compared the efficacy and safety of catheter ablation for AF between CB and RF ablation in patients with HFrEF.

Method:
The CRABL-HF study was designed as a prospective, multicenter, open-label, controlled, and randomized clinical trial comparing the efficacy and safety of AF ablation between CB and RF ablation in patients with HFrEF (LVEF ?40%). The study included 110 patients from Japan, randomly assigned 1:1 to the CB and RF ablation arms. Patients aged 20-85 with LVEF ?40% and a documented AF episode (?30 seconds) were included. Patients with previous AF ablation or surgical procedures, LA diameter >55 mm, and pregnant women were excluded. The primary endpoint of the study was the occurrence of atrial tachycardia (AT; lasting 30 seconds or more) 1 year after ablation.

Results:
In the CRABL-HF study, patients assigned to the CB and RF ablation arms were followed for 12 months. The primary endpoint, the occurrence of atrial tachycardia 1 year after ablation, was 22.2% in the CB arm and 21.8% in the RF arm. There was no statistically significant difference between the two groups for the primary endpoint. Looking at secondary endpoints, the average procedure time was 101 minutes for the CB ablation group and 165 minutes for the RF ablation group. There was one death in each group. LVEF increased by 18% in the CB ablation group and by 23% in the RF ablation group.

Conclusion:
Cryoballoon (CB) ablation is as safe and effective as radiofrequency (RF) ablation for correcting the underlying cause of atrial fibrillation (AF) in heart failure patients with reduced ejection fraction (HFrEF). Additionally, it offers benefits such as reduced hemodynamic burden and shorter procedure times.

Comment:
The CRABL-HF study demonstrates that cryoballoon (CB) ablation is as effective and safe as radiofrequency (RF) ablation in patients with heart failure and low ejection fraction. CB ablation may be preferred in patients with low LVEF due to its shorter procedure time.