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Introduction: Strategies beyond pulmonary vein isolation (PVI) in persistent atrial fibrillation (persAF) are debated. A novel mapping tool provides algorithmic detection of ablation targets based on electrogram (EGM) properties specific to stable localized rotational activations. Methods: The mapping tool was used on 31 patients (20 de novo). The algorithm was used to optimize PVI line placement and guide additional ablations. Targets were detected by calculating local cycle length (L‐CL) and local spread of activation within that L‐CL (Duty Cycle; DC) for EGMs with consistent morphology and activation. At least two left atrial (LA) maps (pre‐PVI and post‐PVI) were acquired in atrial fibrillation (AF) in all patients (except those with AF termination during PVI). Extra‐pulmonary vein (PV) targets were compared between the two LA maps in each patient. Follow‐up included Holter monitoring every 3 months. Results: Patients had a median of 3 extra‐PV drivers/targets. The majority (81%) were localized in the same areas between the two LA maps. All patients had progressive AF organization demonstrated by global activation slowing: histogram peak L‐CL increased from 162 to 171 ms (post‐PVI; p =.0003) than to 175 ms (posttarget ablation; p =.04). Moreover, L‐CL dispersion was reduced by ablation; in 50% their values tended to cluster around two dominant cycles. In de novo patients AF terminated to sinus rhythm or atrial tachycardia (AT) within 48 h postprocedure in 88% of cases, and at 18 months mean follow‐up recurrence occurred in only five (25%) patients (three persAF, two AT). There were no complications. Conclusion: The algorithmic detection of EGMs consistent with localized reentry during sequential mapping of persAF provided reproducible targets for ablation. This allowed personalized PVI and limited, highly‐selective, extra‐PV ablation. Results of this initial experience included progressive organization of AF with ablation and a low recurrence rate after a single procedure. [ABSTRACT FROM AUTHOR]

Fabrication of catalytically active electrodes by electrodeposition is attractive due to its in situ nature, easy controllability, and large-scale operation capability. Most recently, modifying the electrodes with phosphate ligands through electrodepositing electrode materials has shown promising results in improving the kinetics of some reactions. However, it is unclear how the presence of phosphate anions affects the electrodeposition process and functions in catalyzing reactions. Here, we report a systematic study on electrodeposition of Cu in the presence of phosphate anions. The phosphate anions form a complex with free Cu(ii) cations, competing with the electrodeposition process. The competition between the two processes results in an insufficient supply of free Cu(ii) for electrodeposition, especially at the diffusion layer. This is evidenced by the calculation of free Cu(ii) concentration and the electrodeposition current at identical applied potentials. We also found that the electrodeposition of Cu in the presence of phosphate generates Cu-oxyo/hydroxyo-phosphate species on the deposited copper surface. The modified electrodes with phosphate species exhibit higher selectivity for HCOOH formation (faradaic efficiency ∼80%) from the electrochemical reduction of CO2 as compared with Cu foil (faradaic efficiency ∼33%). The effect of phosphate ligands promoting HCOOH selectivity is further verified by stripping off the ligands and regenerating the ligands.