Cryoablation scores over drugs as first-line therapy for AF, Cryo-FIRST study.

Treatment guidelines for patients with atrial fibrillation (AF) suggest that patients should be managed with an antiarrhythmic drug (AAD) before undergoing catheter ablation (CA). However, the results from the Cryo-FIRST study published in EUROPACE journal have now challenged this conventional recommendation by stating that Cryoballoon ablation is superior to antiarrhythmic drug (AAD) therapy and significantly reduces atrial arrhythmia (AA) recurrence in treatment-naive patients with paroxysmal atrial fibrillation (PAF) with a similar rate of adverse events.

Most comparisons between CA and AAD therapy have been completed in patients deemed as 'AAD-refractory' before study enrolment. These studies have consistently demonstrated that CA is superior to AADs for the reduction of AA recurrence and the avoidance of AF disease progression. Accordingly, the use of CA has received a Class I recommendation in patients with symptomatic, drug-refractory PAF in current guidelines.

However, the safety and efficacy of CA vs. AADs as a first-line treatment has not been as extensively investigated in large randomized trials (especially when considering cryoballoon CA), and consequently, the usage of CA as a first-line treatment has received a Class IIa recommendation.

Against this background, Kuniss et al randomised 218 treatment naive patients with symptomatic PAF to cryoballoon CA (Arctic Front Advance, Medtronic) or AAD (Class I or III) and followed for 12 months. The primary endpoint was ≥1 episode of recurrent AA (AF, atrial flutter, or atrial tachycardia) >30 s after a prespecified 90-day blanking period. Secondary endpoints included the rate of serious adverse events (SAEs) and recurrence of symptomatic palpitations (evaluated via patient diaries).

Freedom from AA was achieved in 82.2% of subjects in the cryoballoon arm and 67.6% of subjects in the AAD arm (HR = 0.48, P = 0.01). There were no group differences in the time-to-first or overall incidence of SAEs. The incidence rate of symptomatic palpitations was lower in the cryoballoon compared with the AAD arm.

This prospective, randomized global study evaluated cryoballoon catheter ablation vs. antiarrhythmic drug therapy as an initial, first-line rhythm control strategy in patients with symptomatic paroxysmal atrial fibrillation.

Importantly, there were no occurrences of death, atrio-oesophageal fistula, stroke, pericardial tamponade, or chronic phrenic nerve injury within the CA cohort in the present trial. Overall, these findings align with those recently reported in STOP AF First and EARLY-AF; both of these studies observed SAEs in a similar proportion of patients randomized to first-line cryoballoon CA as AAD therapy. Moreover, these results support a growing body of literature demonstrating that CA can be safely performed by experienced operators.

Also Read:Cryoablation or Drug Therapy for Initial Treatment of Atrial Fibrillation

These findings suggest that cryoballoon ablation is an effective first-line treatment strategy in drug naive patients with symptomatic paroxysmal atrial fibrillation pursing rhythm control therapy.

Source: EP Europace, euab029, https://doi.org/10.1093/europace/euab029