Long Term Outcome and Pulmonary Vein Reconnection of Patients Undergoing Cryoablation and/or Radiofrequency Ablation: Results from The Cryo Versus RF Trial.

Abstract

Long term prospective data comparing the efficacy of radiofrequency (RF) and cryoballoon ablation (CRYO) for paroxysmal atrial fibrillation (PAF) is lacking. We report the long-term outcomes of a randomized control trial comparing CRYO to RF ablation, or a novel COMBINED approach (RF followed by CRYO) for PAF. We studied the number and pattern of pulmonary vein (PV) reconnections in patients undergoing repeat procedure(s). The COMBINED approach had significantly higher single procedure success rate and is associated with the fewest reconnected PVs. 203 patients who underwent first time PAF ablation in a randomized clinical trial comparing CRYO (67), RF (67) and COMBINED (69) approaches were followed up. All patients with symptomatic recurrence of AF were offered a repeat procedure(s). Reconnected PV(s) at repeat procedure(s) were recorded. In a subset, the PV reconnection sites during the first repeat procedure were prospectively assessed and categorised into one of 8 segments. . At 5 years, 57% of COMBINED patients remained free of AF after a single procedure compared to 47% CRYO and 19% RF patients (p<0.001 COMBINED vs RF and CRYO vs RF, p=0.043 COMBINED vs CRYO). During the first repeat procedure, theCOMBINED group had less number of reconnected PVs (mean number of reconnected PVs in the COMBINED group 1.2 vs 2.3 CRYO and 2.4 RF, p=0.034). There was a different pattern of PV reconnection comparing the CRYO and RF groups. The COMBINED approach had a significantly higher single procedure success rate with fewer reconnected PVs and fewer reconnection sites compared to either CRYO or RF alone. CRYO in turn was superior to RF. PV reconnection pattern differed between CRYO and RF and the synergistic effect of the COMBINED approach may explain the improved single procedure efficacy.