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Competing Interests: Disclosures The authors have no conflicts to disclose.

Competing Interests: Disclosures Dr Hyman is a consultant for Asahi Intecc, Inc. All other authors have no conflicts of interest to disclose.

Background: Targeting non-pulmonary vein triggers (NPVTs) after pulmonary vein isolation may reduce atrial fibrillation (AF) recurrence. Isoproterenol infusion and cardioversion of spontaneous or induced AF can provoke NPVTs but typically require vasopressor support and increased procedural time., Objective: The purpose of this study was to identify risk factors for the presence of NPVTs and create a risk score to identify higher-risk subgroups., Methods: Using the AF ablation registry at the Hospital of the University of Pennsylvania, we included consecutive patients who underwent AF ablation between January 2021 and December 2022. We excluded patients who did not receive NPVT provocation testing after failing to demonstrate spontaneous NPVTs. NPVTs were defined as non-pulmonary vein ectopic beats triggering AF or focal atrial tachycardia. We used risk factors associated with NPVTs with P <.1 in multivariable logistic regression model to create a risk score in a randomly split derivation set (80%) and tested its predictive accuracy in the validation set (20%)., Results: In 1530 AF ablations included, NPVTs were observed in 235 (15.4%). In the derivation set, female sex (odds ratio [OR] 1.40; 95% confidence interval [CI] 0.96-2.03; P = .080), sinus node dysfunction (OR 1.67; 95% CI 0.98-2.87; P = .060), previous AF ablation (OR 2.50; 95% CI 1.70-3.65; P <.001), and left atrial scar (OR 2.90; 95% CI 1.94-4.36; P <.001) were risk factors associated with NPVTs. The risk score created from these risk factors (PRE 2 SSS 2 score; [PRE]vious ablation: 2 points, female [S]ex: 1 point, [S]inus node dysfunction: 1 point, left atrial [S]car: 2 points) had good predictive accuracy in the validation cohort (area under the receiver operating characteristic curve 0.728; 95% CI 0.648-0.807)., Conclusion: A risk score incorporating predictors for NPVTs may allow provocation of triggers to be performed in patients with greatest expected yield., Competing Interests: Disclosures Dr Marchlinski has served as consultant for Abbott Medical, Biosense Webster, Biotronik, and Medtronic Inc. All other authors have no conflicts of interest to disclose., (Copyright © 2024 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: His-bundle pacing (HBP) is an appealing alternative to right ventricular pacing in patients referred for permanent ventricular pacing and atrioventricular nodal ablation (AVNA) because it preserves physiological ventricular activation. Only limited data regarding HBP combined with AVNA are available in the literature., Objective: The purpose of this study was to provide further evidence on the feasibility and efficacy of this therapeutic approach in patients with uncontrolled atrial arrhythmia., Methods: We prospectively included all patients who had undergone AVNA after HBP in 3 different hospitals between 2017 and 2022., Results: AVNA following HBP lead implantation was performed in 75 patients. Complete atrioventricular (AV) block was obtained in 58 patients (77%), and significant modulation of AV nodal conduction (heart rate <60 bpm) was obtained in 12 patients (16%). AVNA failure was observed in 5 patients (7%). Recording of an atrial signal by the HBP lead was more frequently observed in patients with AVNA modulation/failure than in patients with complete AV block (11/17 vs 5/58; P <.001). No lead dislodgment occurred during the AVNA procedures. Acute His-bundle (HB) capture threshold increase >1 V occurred in 11 patients (15%), with return to baseline value on day 1 in 9 patients. New York Heart Association functional class and left ventricular ejection fraction significantly improved from baseline to last follow-up (3.0 ± 0.7 vs 1.6 ± 0.5; P <.001; and 47% ± 14% vs 60% ± 9%; P <.0001, respectively)., Conclusion: AVNA combined with HBP for noncontrolled atrial arrhythmia was feasible and clinically efficient. Implanting the HB lead on the ventricular aspect of the tricuspid annulus avoiding atrial signal recording can facilitate AVNA., (Copyright © 2023. Published by Elsevier Inc.)

Pesticides lead to surface water pollution and ecotoxicological effects on aquatic biota. Novel strategies are required to evaluate the contribution of degradation to the overall pesticide dissipation in surface waters. Here, we combined polar organic chemical integrative samplers (POCIS) with compound-specific isotope analysis (CSIA) to trace in situ pesticide degradation in artificial ponds and agricultural streams. The application of pesticide CSIA to surface waters is currently restricted due to environmental concentrations in the low μg.L -1 range, requiring processing of large water volumes. A series of laboratory experiments showed that POCIS enables preconcentration and accurate recording of the carbon isotope signatures (δ 13 C) of common pesticides under simulated surface water conditions and for various scenarios. Commercial and in-house POCIS did not significantly (Δδ 13 C < 1 %) change the δ 13 C of pesticides during uptake, extraction, and δ 13 C measurements of pesticides, independently of the pesticide concentrations (1-10 μg.L -1 ) or the flow speeds (6 or 14 cm.s -1 ). However, simulated rainfall events of pesticide runoff affected the δ 13 C of pesticides in POCIS. In-house POCIS coupled with CSIA of pesticides were also tested under different field conditions, including three flow-through and off-stream ponds and one stream receiving pesticides from agricultural catchments. The POCIS-CSIA method enabled to determine whether degradation of S-metolachlor and dimethomorph mainly occurred in agricultural soil or surface waters. Comparison of δ 13 C of S-metolachlor in POCIS deployed in a stream with δ 13 C of S-metolachlor in commercial formulations suggested runoff of fresh S-metolachlor in the midstream sampling site, which was not recorded in grab samples. Altogether, our study highlights that the POCIS-CSIA approach represents a unique opportunity to evaluate the contribution of degradation to the overall dissipation of pesticides in surface waters., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Microbial electrochemical snorkel (MES) is a short-circuited microbial fuel cell applicable to water treatment that does not produce energy but requires lower cost for its implementation. Few reports have already described its water treatment capabilities but no deeper electrochemical analysis were yet performed. We tested various materials (iron, stainless steel and porous graphite) and configurations of snorkel in order to better understand the rules that will control in a wetland the mixed potential of this self-powered system. We designed a model snorkel that was studied in laboratory and on the field. We confirmed the development of MES by identifying anodic and cathodic parts, by measuring the current between them and by analyzing microbial ecology in laboratory and field experiments. An important application is denitrification of surface water. Here we discuss the influence of nitrate on its electrochemical response and denitrification performances. Introducing nitrate caused the increase of the mixed potential of MES and of current at a potential value relatively more positive than for nitrate-reducing biocathodes described in the literature. The major criteria for promoting application of MES in artificial wetland dedicated to mitigation of non-point source nitrate pollution from agricultural water are considered., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

To limit the nitrate contamination of ground and surface water, stimulation of denitrification by electrochemical approach is an innovative way to be explored. Two nitrate reducing bio-cathodes were developed under constant polarization (-0.5 V vs SCE) using sediments and water from a constructed wetland (Rampillon, Seine-et-Marne, France). The bio-cathodes responded to nitrate addition on chronoamperometry through an increase of the reductive current. The denitrification efficiency of the pilots increased by 47% compared to the negative controls without electrodes after polarization. 16S rRNA gene sequencing of the biofilms and sediments evidenced the significant and discriminating presence of the Azoarcus and Pontibacter genera in the biofilms from biocathodes active for nitrate reduction. Our study shows the possibility to promote the development of efficient Azoarcus-dominated biocathodes from freshwater sediment to enhance nitrate removal from surface waters., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Constructed wetlands (CW) can efficiently remove nitrogen from polluted agricultural run-off, however, a potential caveat is nitrous oxide (N 2 O), a harmful greenhouse gas and stratospheric ozone depleter. During five sampling campaigns, we measured N 2 O fluxes from a 0.53 ha off-stream CW treating nitrate-rich water from the intensively fertilized watershed in Rampillon, France, using automated chambers with a quantum cascade laser system, and manual chambers. Sediment samples were analysed for potential N 2 flux using the HeO 2 incubation method. Both inlet nitrate (NO 3 - ) concentrations and N 2 O emission varied significantly between the seasons. In the Autumn and Winter inlet concentrations were about 11 mg NO 3 - -N L -1 , and < 6.5 mg NO 3 - -N L -1 in the Spring and Summer. N 2 O emission was highest in the Autumn (mean ± standard error: 9.7 ± 0.2 μg N m -2  h -1 ) and lowest in the Summer (wet period: 0.2 ± 0.3 μg N m -2  h -1 ). The CW was a very weak source of N 2 O emitting 0.32 kg N 2 O-N ha -1  yr -1 and removing around 938 kg NO 3 - -N ha -1  yr -1 , the ratio of N 2 O-N emitted to NO 3 - -N removed was 0.033%. The automated and manual chambers gave similar results. From the potential N 2 O formation in the sediment, only 9% was emitted to the atmosphere, the average N 2 N 2 O ratio was high: 89:1 for N 2 -N potential : N 2 O-N potential and 1353:1 for N 2 -N potential : N 2 O-N emitted . These results indicate complete denitrification. The focused principal component analysis showed strong positive correlation between the gaseous N 2 O fluxes and the following environmental factors: NO 3 - -N concentrations in inlet water, streamflow, and nitrate reduction rate. Water temperature, TOC and DOC in the water and hydraulic residence time showed negative correlations with N 2 O emissions. Shallow off-stream CWs such as Rampillon may have good nitrate removal capacity with low N 2 O emissions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)