An Individualised Ablation Strategy to Treat Persistent Atrial Fibrillation: Core-to-Boundary Approach Guided by Charge-Density Mapping

Abstract Background Non-contact charge-density mapping allows rapid real-time global mapping of atrial fibrillation (AF) offering the opportunity of a personalised ablation strategy. Objective We compared the two-year outcome of an individualised strategy consisting of pulmonary vein isolation (PVI) plus Core-to-Boundary ablation (targeting the conduction pattern core with an extension to the nearest non-conducting boundary) guided by charge-density mapping, with an empirical PVI plus posterior wall electrical isolation (PWI) strategy. Methods Forty patients (62±12 years, 29 males) with persistent AF (10±5 months) prospectively underwent charge-density mapping guided PVI followed by Core-to-Boundary stepwise ablation until termination of AF or depletion of identified cores. Freedom from AF/atrial tachycardia (AT) at 24-months was compared with a propensity-score matched control group of 80 patients with empirical PVI+PWI guided by conventional contact mapping. Results Acute AF termination occurred in 8/40 patients following charge-density mapping guided PVI alone and in 21 of the remaining 32 patients following Core-to-Boundary ablation in the study cohort, compared with 8/80 (10%) in the control cohort; p＜0.001. On average, 2.2±0.6 cores were ablated post-PVI before acute AF termination. At 24-months, freedom from AF/AT following a single procedure was 68% in the study group vs. 46% in the control group; p=0.043. Conclusion An individualised ablation strategy consisting of PVI plus Core-to-Boundary ablation guided by noncontact charge-density mapping is a feasible and effective strategy in treating persistent AF with a favourable 24-month outcome.