Sequential hybrid ablation vs. surgical CryoMaze alone for treatment of atrial fibrillation: results of multicentre randomized controlled trial.

ABSTRACT

AIMS: Data on the hybrid atrial fibrillation (AF) treatment are lacking in patients with structural heart disease undergoing concomitant CryoMaze procedures. The aim was to assess whether the timely pre-emptive catheter ablation would achieve higher freedom from AF or atrial tachycardia (AT) and be associated with better clinical outcomes than surgical ablation alone. METHODS AND RESULTS: The trial investigated patients with non-paroxysmal AF undergoing coronary artery bypass grafting and/or valve repair/replacement with mandatory concomitant CryoMaze procedure who were randomly assigned to undergo either radiofrequency catheter ablation [Hybrid Group (HG)] or no further treatment (Surgery Group). The primary efficacy endpoint was the first recurrence of AF/AT without class I or III antiarrhythmic drugs as assessed by implantable cardiac monitors. The primary clinical endpoint was a composite of hospitalization for arrhythmia recurrence, worsening of heart failure, cardioembolic event, or major bleeding. We analysed 113 and 116 patients in the Hybrid and Surgery Groups, respectively, with a median follow-up of 715 (IQR 528-1072) days. The primary efficacy endpoint was significantly reduced in the HG [41.1% vs. 67.4%, hazard ratio (HR) = 0.38, 95% confidence interval (CI) 0.26-0.57, P < 0.001] as well as the primary clinical endpoint (19.9% vs. 40.1%, HR = 0.51, 95% CI 0.29-0.86, P = 0.012). The trial groups did not differ in all-cause mortality (10.6% vs. 8.6%, HR = 1.17, 95%CI 0.51-2.71, P = 0.71). The major complications of catheter ablation were infrequent (1.9%). CONCLUSION: Pre-emptively performed catheter ablation after the CryoMaze procedure was safe and associated with higher freedom from AF/AT and improved clinical outcomes.