"Cryoballoon or Radiofrequency Ablation for Paroxysmal Atrial Fibrillation". The New England Journal of Medicine. 2016.
Links to original sources: Wiki Journal Post Full Journal Article
In symptomatic patients with drug-refractory paroxysmal atrial fibrillation, is cryoballoon ablation noninferior to radiofrequency ablation in terms of efficacy and safety?
Cryoballoon ablation was noninferior to radiofrequency ablation with respect to treatment efficacy in patients with drug-refractory paroxysmal atrial fibrillation, and there was no significant difference in the overall safety profile between the two methods.
Both cryoballoon and radiofrequency ablation are used for pulmonary-vein isolation in the treatment of atrial fibrillation. This multicenter, randomized trial compared these two methods to determine their efficacy and safety in treating paroxysmal atrial fibrillation.
Current guidelines recommend catheter ablation with pulmonary-vein isolation as a class I level A indication for drug-refractory paroxysmal atrial fibrillation.
- Multicenter, randomized, noninferiority, parallel-group, open-label trial with blinded endpoint assessment. - N=762 patients with symptomatic, drug-refractory paroxysmal atrial fibrillation. - Interventions: Cryoballoon ablation (n=378) or radiofrequency ablation (n=384). - Follow-up: Mean period of 1.5 years. - Primary efficacy endpoint: First documented clinical failure (recurrence of AF, occurrence of atrial flutter or tachycardia, use of antiarrhythmic drugs, or repeat ablation) after a 90-day post-ablation blanking period. - Primary safety endpoint: Composite of death, cerebrovascular events, or serious treatment-related adverse events. Population - 16 centers in 8 countries participated. - Patients aged ≥18 years with symptomatic paroxysmal atrial fibrillation that was refractory to class I or III antiarrhythmic drugs or beta blockers were eligible. Interventions - Cryoballoon ablation: Attempted pulmonary-vein isolation using a cryoballoon filled with liquid refrigerant to cool and ablate tissue. - Radiofrequency ablation: Attempted pulmonary-vein isolation with point-by-point applications of radiofrequency energy, using electroanatomical navigation.
- Primary efficacy endpoint occurred in 138 patients in the cryoballoon group and 143 in the radiofrequency group (hazard ratio, 0.96; 95% CI, 0.76 to 1.22; P<0.001 for noninferiority). - Primary safety endpoint occurred in 40 patients in the cryoballoon group and in 51 patients in the radiofrequency group (hazard ratio, 0.78; 95% CI, 0.52 to 1.18; P=0.24). - The mean total procedure time was shorter for cryoballoon ablation, whereas the mean total fluoroscopy time was shorter for radiofrequency ablation. - No significant difference in time to first rehospitalization for cardiovascular causes between the groups.
- Open-label design may introduce bias. - Complete isolation was not achieved in all patients. - Some utilized catheters were of the first generation, potentially affecting outcomes relative to newer-generation catheters.
The trial was funded by Medtronic.
The article "Cryoballoon or Radiofrequency Ablation for Paroxysmal Atrial Fibrillation" as published in The New England Journal of Medicine, April 4, 2016.