Recurrences in the Blanking Period and 12‐Month Success Rate by Continuous Cardiac Monitoring After Cryoablation of Paroxysmal and Non‐Paroxysmal Atrial Fibrillation
Recurrences occurring within 3 months from the index procedure (i.e., the “blanking” period) are common, but their long‐term clinical significance is still controversial, as up to the half of patients with early recurrences were reported not to experience recurrences thereafter,15 and delaying repeat procedures is still suggested.18 Therefore, the 2012 joint American and European Expert Consensus Statement recommends that recurrences of atrial tachycardia (AT)/AF within the first 3 months should not be classified as treatment failure.19 However, this paradigm has been recently challenged by new evidence, with either RF20 or CB8 ablation: higher rates of late recurrences after early recurrences were reported22 and performing early second ablation has been suggested as a very effective strategy to restore stable SR.22
Determining the exact success rate of AF ablation is challenging, as symptoms are poorly correlated with AF relapses after ablation,24 while, on the other hand, intermittent cardiac monitoring has low sensitivity in detecting recurrences. So far, few authors have used continuous monitoring for detecting recurrences,23 and mostly limited to RF PVI. The use of a dedicated device, such as an implantable loop recorder (ILR), offers very high diagnostic accuracy,27 helps stratify the risk of subsequent major adverse events,29 and identifies the timing for repeat ablation.
In the present investigation we aimed at (1) assessing, by means of ILRs, the real incidence of early and late recurrences, in a cohort of consecutive patients with paroxysmal and persistent/longstanding (LS) persistent AF, undergoing their first CB ablation procedure, (2) evaluating the role of within‐blanking AT/AF events in predicting ablation failure at 12 months, and (3) identifying the predictors of recurrences.