Efficacy
The 79.9% recurrence rate reported here is higher than reports from
recent meta-analysis of treatment success for PAF, cryoablation (28%
recurrence) AADs (45% recurrence).22 Additionally,
the current data are promising in light of historic studies of the
effectiveness of cryoablation.1 Though it used
different endpoints, FIRE and ICE reported cryoballoon effectiveness of
65%, with 87/376 pts (23%) having documented recurrence of atrial
arrythmia.23 STOP AF reported a 69% overall
effectiveness of cryoablation3 though that study
allowed continued treatment with the same dose of previously ineffective
AADs but used a first generation cryoballoon. Cryo-First reported
similar outcomes to the current study, with an 82.2% freedom from
recurrence of atrial arrythmia in early PAF patients with no AAD
history.24 It should be noted that outcomes might be
improved in patients undergoing ablation prior to trials of
antiarrhythmic drugs and thus early in the course of their disease.. A
recent study of a pulsed field ablation (PFA) system of 150 paroxysmal
AF patients had a markedly higher rate of documented recurrence (33.8 vs
the present 19.1) and more repeat ablations (8% vs the present
4.4%).25 A recent randomized controlled trial
comparing PFA to thermal (Cryo and RF) ablation modalities also aids in
putting this data in perspective, ADVENT reported a 73% and 71%
effectiveness for PFA and thermal ablation,
respectively.26 The effectiveness of thermal ablation
in that trial was comparable to the present findings, though the
Bayesian analysis used in ADVENT makes direct comparison to traditional
KM analysis challenging. Further insights into the relative
effectiveness of cryoablation and novel PFA systems may have significant
impact on the landscape of AF treatment.