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Demand for real-time detection of hydrogen and ammonia, clean energy carriers, in a sensitive and selective manner, is growing rapidly for energy, industrial, and medical applications. Nevertheless, their selective detection still remains a challenge and requires the utilization of diverse sensors, hampering the miniaturization of sensor modules. Herein, a practical approach via material design and facile temperature modulation for dual selectivity is proposed. A Pd nanoparticles-decorated W 18 O 49 nanowire gas sensor is prepared for dual detection of hydrogen and ammonia. The sensor exhibits distinct operating temperatures for ultraselective detection of hydrogen (125 °C) and ammonia (225 °C), with high responses of 35.3 and 133.8, respectively. This dual selectivity with high sensitivity is attributed to enhanced oxygen adsorption, the chemical affinity of sensing materials for target gases, and distinct reactivity profiles of gases. The proposed sensor is further integrated into a microelectromechanical system, enabling its small size, low power consumption, and rapid temperature modulation. Moreover, the practical feasibility of this sensor platform for smart energy monitoring systems is demonstrated by assessing its sensing properties in electrochemical ammonia oxidation reaction systems. This work can provide a practical approach for developing a single gas sensor with multiple functionalities for application in electronic nose systems., (© 2024 Wiley‐VCH GmbH.)

Hydrogen (H 2 ) is a promising alternative energy source for Net-zero, but the risk of explosion requires accurate and rapid detection systems. As the use of H 2 energy expands, sensors require high performance in a variety of properties. Palladium (Pd) is an attractive material for H 2 detection due to its high H 2 affinity and catalytic properties. However, poor stability caused by volume changes and reliability due to environmental sensitivity remain obstacles. This study proposes a micropatterned thin film of PdAu with optimized composition (Pd 0.62 Au 0.38 ) as a chemoresistive sensor to overcome these issues. At room temperature, the sensor has a wide detection range of 0.0002% to 5% and a fast response time of 9.5 s. Significantly, the sensor exhibits excellent durability for repeated operation (>35 h) in 5% H 2 and resistance to humidity and carbon monoxide. We also report a negative resistivity change in PdAu, which is opposite to that of Pd. Density functional theory (DFT) calculations were performed to investigate the resistance change. DFT analysis revealed that H 2 penetrates specific interstitial sites, causing partial lattice compression. The lattice compression causes a decrease in electrical resistance. This work is expected to contribute to the development of high-performance H 2 sensors using Pd-based alloys.

Background: Heart rate turbulence (HRT) and T-wave alternans (TWA), recognized as promising noninvasive markers for ventricular tachyarrhythmias and cardiac death, have been studied predominantly in Western populations, specifically in patients with myocardial infarction (MI) or heart failure (HF) with reduced ejection fraction (EF)., Objective: The purpose of this study was to investigate the clinical implications of HRT and TWA in predicting adverse cardiac events, including cardiac death, ventricular tachyarrhythmia, and heart failure-related hospitalization (HFH)., Methods: The K-REDEFINE study, a prospective, observational, multicenter analysis of 26 tertiary hospitals in South Korea, investigated the prognostic implications of Holter-based variables including HRT and TWA in 1116 patients with acute MI or HF (age 60.8 ± 2.9 years; 76.3% male). All participants underwent 24-hour Holter recording within 6.8 ± 16.5 days after hospitalization. The primary composite outcome included cardiac death, ventricular tachyarrhythmias, and HFH., Results: During 4.3 ± 1.2 years of follow-up, impaired HRT demonstrated the most powerful predictive value for the composite (adjusted hazard ratio [aHR] 3.41, 95% confidence interval [CI] 2.27-5.13) or individual events: cardiac death (aHR 4.08, 95% CI 2.17-7.70), ventricular tachyarrhythmia (aHR 3.72, 95% CI 1.29-10.77), and HFH (aHR 4.32, 95% CI 2.25-8.28). The predictive power of abnormal HRT remained consistently significant across subgroups of MI and HF, or across varying degrees of EF. When combined with reduced EF (<50%), the predictive power was further enhanced. However, abnormal TWA was significantly associated only with the composite outcome (aHR 1.51, 95% CI 1.06-2.16)., Conclusion: The K-REDEFINE study identified abnormal HRT, mostly assessed within 1 month after hospitalization, as a significant predictor not only for cardiac death and ventricular tachyarrhythmia but also for HFH., Competing Interests: Disclosures The authors have no conflicts to disclose., (Copyright © 2024 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: Despite consistent recommendations from clinical guidelines, data from randomized trials on a long-term antithrombotic treatment strategy for patients with atrial fibrillation and stable coronary artery disease are still lacking., Methods: We conducted a multicenter, open-label, adjudicator-masked, randomized trial comparing edoxaban monotherapy with dual antithrombotic therapy (edoxaban plus a single antiplatelet agent) in patients with atrial fibrillation and stable coronary artery disease (defined as coronary artery disease previously treated with revascularization or managed medically). The risk of stroke was assessed on the basis of the CHA 2 DS 2 -VASc score (scores range from 0 to 9, with higher scores indicating a greater risk of stroke). The primary outcome was a composite of death from any cause, myocardial infarction, stroke, systemic embolism, unplanned urgent revascularization, and major bleeding or clinically relevant nonmajor bleeding at 12 months. Secondary outcomes included a composite of major ischemic events and the safety outcome of major bleeding or clinically relevant nonmajor bleeding., Results: We assigned 524 patients to the edoxaban monotherapy group and 516 patients to the dual antithrombotic therapy group at 18 sites in South Korea. The mean age of the patients was 72.1 years, 22.9% were women, and the mean CHA 2 DS 2 -VASc score was 4.3. At 12 months, a primary-outcome event had occurred in 34 patients (Kaplan-Meier estimate, 6.8%) assigned to edoxaban monotherapy and in 79 patients (16.2%) assigned to dual antithrombotic therapy (hazard ratio, 0.44; 95% confidence interval [CI], 0.30 to 0.65; P<0.001). The cumulative incidence of major ischemic events at 12 months appeared to be similar in the trial groups. Major bleeding or clinically relevant nonmajor bleeding occurred in 23 patients (Kaplan-Meier estimate, 4.7%) in the edoxaban monotherapy group and in 70 patients (14.2%) in the dual antithrombotic therapy group (hazard ratio, 0.34; 95% CI, 0.22 to 0.53)., Conclusions: In patients with atrial fibrillation and stable coronary artery disease, edoxaban monotherapy led to a lower risk of a composite of death from any cause, myocardial infarction, stroke, systemic embolism, unplanned urgent revascularization, or major bleeding or clinically relevant nonmajor bleeding at 12 months than dual antithrombotic therapy. (Funded by the CardioVascular Research Foundation and others; EPIC-CAD ClinicalTrials.gov number, NCT03718559.)., (Copyright © 2024 Massachusetts Medical Society.)

Micro-light-emitting diodes (μLEDs) have gained significant interest as an activation source for gas sensors owing to their advantages, including room temperature operation and low power consumption. However, despite these benefits, challenges still exist such as a limited range of detectable gases and slow response. In this study, we present a blue μLED-integrated light-activated gas sensor array based on SnO 2 nanoparticles (NPs) that exhibit excellent sensitivity, tunable selectivity, and rapid detection with micro-watt level power consumption. The optimal power for μLED is observed at the highest gas response, supported by finite-difference time-domain simulation. Additionally, we first report the visible light-activated selective detection of reducing gases using noble metal-decorated SnO 2 NPs. The noble metals induce catalytic interaction with reducing gases, clearly distinguishing NH 3 , H 2 , and C 2 H 5 OH. Real-time gas monitoring based on a fully hardware-implemented light-activated sensing array was demonstrated, opening up new avenues for advancements in light-activated electronic nose technologies., (© 2024. The Author(s).)

Background: There is limited information on the mode of arrhythmia initiation in idiopathic ventricular fibrillation (IVF). A non-pause-dependent mechanism has been suggested to be the rule., Objectives: The aim of this study was to assess the mode and characteristics of initiation of polymorphic ventricular tachycardia (PVT) in patients with short or long-coupled PVT/IVF included in THESIS (THerapy Efficacy in Short or long-coupled idiopathic ventricular fibrillation: an International Survey), a multicenter study involving 287 IVF patients treated with drugs or radiofrequency ablation., Methods: We reviewed the initiation of 410 episodes of ≥1 PVT triplet in 180 patients (58.3% females; age 39.6 ± 13.6 years) with IVF. The incidence of pause-dependency arrhythmia initiation (prolongation by >20 ms of the preceding cycle length) was assessed., Results: Most arrhythmias (n = 295; 72%) occurred during baseline supraventricular rhythm without ambient premature ventricular complexes (PVCs), whereas 106 (25.9%) occurred during baseline rhythm including PVCs. Nine (2.2%) arrhythmias occurred during atrial/ventricular pacing and were excluded from further analysis. Mode of PVT initiation was pause-dependent in 45 (15.6%) and 64 (60.4%) of instances in the first and second settings, respectively, for a total of 109 of 401 (27.2%). More than one type of pause-dependent and/or non-pause-dependent initiation (mean: 2.6) occurred in 94.4% of patients with ≥4 events. Coupling intervals of initiating PVCs were <350 ms, 350-500 ms, and >500 ms in 76.6%, 20.72%, and 2.7% of arrhythmia initiations, respectively., Conclusions: Pause-dependent initiation occurred in more than a quarter of arrhythmic episodes in IVF patients. PVCs having long (between 350 and 500 ms) and very long (>500 ms) coupling intervals were observed at the initiation of nearly a quarter of PVT episodes., Competing Interests: Funding Support and Author Disclosures The authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2024 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Left atrial thrombus (LAT) formation is associated with thromboembolic events., Objective: To investigate the incidence and associated factors of LAT in patients with atrial fibrillation (AF) who had been receiving anticoagulation therapy for more than 4 weeks, and to develop a prediction model using clinical and echocardiographic features., Methods: Medical records of 1,122 patients with AF (mean age, 59.4 ± 11.0 years, 58.3% male) who were on anticoagulation more than 4 weeks and underwent transesophageal echocardiography (TEE) were evaluated. The main outcome was the presence of LAT on TEE., Results: Warfarin and non-vitamin K oral anticoagulants were used in 74.4% and 25.6% of the patients at the time of examination, respectively. LAT was present in 60 patients (5.3%). Presence of LAT on TEE was associated with age ≥ 75 years (odds ratio [OR] 2.13 [95% confidence interval, 0.94-4.58]), persistent/permanent AF (OR 2.61 [1.42-4.93]), CHA 2 DS 2 -VASc score ≥ 3 points (OR 1.91 [1.05-3.48]), left ventricular ejection fraction < 40% (OR 2.35 [1.07-4.81]), and severe left atrial enlargement (OR 3.52 [1.89-6.79]). The presence of moderate-to-severe mitral regurgitation was associated with a lower risk of LAT (OR 0.13 [0.04-0.34]). A scoring system composed of the aforementioned predictors showed excellent discrimination performance (area under the curve 0.791 [95% CI, 0.727-0.854])., Conclusions: LAT was present in a considerable number of patients who were already receiving anticoagulation therapy. A prediction model that combines clinical and echocardiographic predictors could be useful in distinguishing patients who require imaging evaluations before left atrial intervention., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)

Introduction: The impact of early recurrence of atrial tachyarrhythmia (ERAT) within the 90-day blanking period on long-term outcomes in atrial fibrillation (AF) patients undergoing cryoballoon ablation (CBA) is controversial. This study aimed to assess the relationship between ERAT and late recurrence of atrial tachyarrhythmia (LRAT) post-CBA., Methods: Utilizing data from a multicenter registry in Korea (May 2018 to June 2022), we analyzed the presence and timing of ERAT (<30, 30-60, and 60-90 days) and its association with LRAT risk after CBA. LRAT was defined as any recurrence of AF, atrial flutter, or atrial tachycardia lasting more than 30 s beyond the 90 days., Results: Out of 2636 patients, 745 (28.2%) experienced ERAT post-CBA. Over an average follow-up period of 21.2 ± 10.3 months, LRAT was observed in 874 (33.1%) patients. Patients with ERAT had significantly lower 1-year LRAT freedom compared to those without ERAT (42.6% vs. 85.5%, p < .001). Multivariate analysis identified ERAT as a potential predictor of LRAT, with a hazard ratio (HR) of 3.98 (95% confidence interval [CI], 3.47-4.57). Significant associations were noted across all examined time frames (HR, 3.84; 95% CI, 3.32-4.45 in <30 days, HR, 5.53; 95% CI, 4.13-7.42 in 30-60 days, and HR, 4.29; 95% CI, 3.12-5.89 in 60-90 days). This finding was consistently observed across all types of AF., Conclusion: ERAT during the 90-day blanking period strongly predicts LRAT in AF patients undergoing CBA, indicating a need to reconsider the clinical significance of this period., (© 2024 The Author(s). Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.)

The development of hydrogen (H 2 ) gas sensors is essential for the safe and efficient adoption of H 2 gas as a clean, renewable energy source in the challenges against climate change, given its flammability and associated safety risks. Among various H 2 sensors, gasochromic sensors have attracted great interest due to their highly intuitive and low power operation, but slow kinetics, especially slow recovery rate limited its further practical application. This study introduces Pd-decorated amorphous WO 3 nanorods (Pd-WO 3 NRs) as an innovative gasochromic H 2 sensor, demonstrating rapid and highly reversible color changes for H 2 detection. In specific, the amorphous nanostructure exhibits notable porosity, enabling rapid detection and recovery by facilitating effective H 2 gas interaction and efficient diffusion of hydrogen ions (H + ) dissociated from the Pd nanoparticles (Pd NPs). The optimized Pd-WO 3 NRs sensor achieves an impressive response time of 14 s and a recovery time of 1 s to 5% H 2 . The impressively fast recovery time of 1 s is observed under a wide range of H 2 concentrations (0.2-5%), making this study a fundamental solution to the challenged slow recovery of gasochromic H 2 sensors., (© 2024 The Authors. Small published by Wiley‐VCH GmbH.)

Competing Interests: Jun Kim: Research fund from Boston Scientific, Medtronic, Abbott. Honororia from Boston Scientific, Medtronic, Abbott, Biosense-Webster, Novartis, Daichi-Sankyo. Other authors have no conflicts to disclose.

Background: Clinical outcomes after catheter ablation (CA) or pacemaker (PM) implantation for the tachycardia-bradycardia syndrome (TBS) has not been evaluated adequately. We tried to compare the efficacy and safety outcomes of CA and PM implantation as an initial treatment option for TBS in paroxysmal atrial fibrillation (AF) patients., Methods: Sixty-eight patients with paroxysmal AF and TBS (mean 63.7 years, 63.2% male) were randomized, and received CA (n = 35) or PM (n = 33) as initial treatments. The primary outcomes were unexpected emergency room visits or hospitalizations attributed to cardiovascular causes., Results: In the intention-to-treatment analysis, the rates of primary outcomes were not significantly different between the two groups at the 2-year follow-up (19.8% vs. 25.9%; hazard ratio (HR) 0.73, 95% confidence interval (CI) 0.25-2.20, P = 0.584), irrespective of whether the results were adjusted for age (HR 1.12, 95% CI 0.34-3.64, P = 0.852). The 2-year rate of recurrent AF was significantly lower in the CA group compared to the PM group (33.9% vs. 56.8%, P = 0.038). Four patients (11.4%) in the CA group finally received PMs after CA owing to recurrent syncope episodes. The rate of major or minor procedure related complications was not significantly different between the two groups., Conclusion: CA had a similar efficacy and safety profile with that of PM and a higher sinus rhythm maintenance rate. CA could be considered as a preferable initial treatment option over PM implantation in patients with paroxysmal AF and TBS., Trial Registration: KCT0000155., (© 2024. The Author(s).)

Objective: Tricuspid regurgitation (TR) is a progressive disease with high mortality and limited medical treatment options, and its association with atrial fibrillation (AF) has been documented. This study aimed to investigate whether successful rhythm control through catheter ablation for AF could reduce TR severity., Methods: A total of 106 patients with drug-refractory AF with moderate to severe secondary TR who underwent AF ablation were screened from a single-centre ablation registry. Echocardiographic parameter changes (pre-procedure vs 1 day/1 year post-procedure) were analysed. Holter monitoring was performed at 3/6/12 months to assess AF recurrence. The primary outcome was at least one grade TR reduction with its main determinants evaluated., Results: After excluding 36 patients (prior tricuspid valve surgery, intracardiac devices or insufficient data), 70 patients (aged 63.8±9.7 years, 50% female) were analysed. Of these, 17 (24.3%) had severe TR, 55 (78.6%) persistent AF and all restored sinus rhythm with catheter ablation. The primary outcome was achieved in 53 (75.7%) at 1-year assessment (73.6% of moderate and 82.4% of severe TR). There were significant decreases of vena contracta (6.1→3.2 mm) and tricuspid annular diameter (37.3→32.6 mm) at 1 year. Although 25 patients experienced AF recurrence within 1 year, 56 (80%) patients finally maintained sinus rhythm with medical treatment (87% in patients with TR reduction and 59% without). From the multivariate analysis, sinus rhythm maintenance was the most significant determinant of TR reduction (OR 8.3, 95% CI 1.8 to 37.4)., Conclusion: In patients with AF with moderate to severe TR, more than two-thirds of patients experienced reduced TR severity, with notable improvements in echocardiographic parameters. Sinus rhythm maintenance was associated with significant TR reduction., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The anatomic extent of the reentry circuit in idiopathic left posterior fascicular ventricular tachycardia (LPF-VT) is yet to be fully elucidated. We hypothesized that entrainment mapping could be used to delineate the reentry circuit of an LPF-VT, especially including the upper turnaround point., Methods: Twenty-three consecutive LPF-VT patients (mean age, 29 ± 9 years, 18 males) were included. We performed overdrive pacing with entrainment attempts at the left bundle branch (LBB) and the left His bundle (HB) region., Results: Overdrive pacing from the LBB region showed concealed fusion in all 23 patients (post-pacing interval [PPI], 322.1 ± 64.3 ms; tachycardia cycle length [TCL], 319.0 ± 61.6 ms; PPI-TCL, 3.1 ± 4.6 ms) with a long stimulus-to-QRS interval (287.9 ± 58.0 ms, approximately 90% of the TCL). Pacing from the same LBB region at a slightly faster pacing rate showed manifest fusion with antidromic conduction to the LBB and minimal in-and-out time to the LBB potential (PPI-TCL, 21.3 ± 13.7 ms). Overdrive pacing from the left HB region showed manifest fusion with a long PPI-TCL (53.9 ± 22.5 ms)., Conclusions: Our pacing study results suggest that the upper turnaround point in a reentry circuit of the LPF-VT may extend to the proximal His-Purkinje conduction system near the LBB region but below the left HB region. The LPF may constitute the retrograde limb of the reentry circuit., (© 2023 The Authors. Pacing and Clinical Electrophysiology published by Wiley Periodicals LLC.)

Background: Young atrial fibrillation (AF) patients have been underrepresented in studies of radiofrequency catheter ablation (RFCA) and the outcome of RFCA has not been widely addressed. We investigated age-related differences in clinical features, the recurrence of atrial tachyarrhythmia, and its predictors of patients who underwent RFCA for AF., Methods: This is a multicenter prospective study of 2799 patients who underwent RFCA for AF in 2017-2020. The patients were divided into two groups - group A (age < 60 years, n = 1269) and group B (age ≥ 60 years, n = 1530) - and a recurrence of any atrial tachyarrhythmia 1 year after RFCA following a 90-day blanking period was compared., Results: The mean age was 51.6 ± 6.7 and 66.8 ± 5.2 years for groups A and B, respectively. Higher body mass index, smaller left atrium, and more prevalent cardiomyopathy and obstructive sleep apnea were observed in group A. Overall, 1-year atrial tachyarrhythmia-free survival was 85.6% and lower in young patients (83.1% in group A vs. 87.7% in group B, log-rank p < 0.01): adjusted hazard ratio (aHR) of recurrence (95% confidence interval (CI)), 1.45 (1.13-1.86) for group A compared to group B (p < 0.01). The association between younger age and higher recurrence was continuously observed in patients under 60 years. Any non-PV ablation was associated with a lower recurrence of atrial tachyarrhythmia in group B (aHR 0.68 (0.47-0.96), p < 0.05), but not in group A., Conclusions: AF patients younger than 60 years had a higher 1-year AF recurrence after RFCA. Young AF patients might have distinctive pathophysiology of AF requiring more integrated management., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The long-term effect of atrial fibrillation (AF) on the occurrence of significant tricuspid regurgitation (TR) has not been evaluated in depth yet. We aimed to evaluate the incidence and predictors of severe TR in AF patients without structural heart disease (SHD). In 27,797 patients with AF, after excluding those with severe TR, SHD, implanted cardiac device, and no available follow-up echocardiography, clinical data of 4,613 patients (63.0 ± 11.3 years old, 69.7% male) were evaluated. The primary outcome was the occurrence of severe TR on follow-up echocardiography. Severe TR developed in 164 patients (3.6%) during median follow-up of 2.9 years (interquartile range 1.2 to 5.3). Most of the severe TR (72.6%) developed as isolated TR progression, and the others were associated with SHD progression, most commonly mitral regurgitation (68.9%). Severe TR predominantly occurred in older female patients and those with heart failure (HF), chronic kidney disease, persistent AF (PeAF), larger LA, and a higher degree of baseline TR. Specifically, 0.8%, 3.7%, and 34.4% of patients with no, mild, and moderate baseline TR, respectively, had progressed to severe TR (p <0.001). In multivariable analysis, moderate TR (hazard ratio [HR] 12.52 [8.99 to 17.42]), age ≥65 years (HR 2.25 [1.60 to 3.16]), previous HF (HR 1.79 [1.13 to 2.85]), PeAF (HR 1.54 [1.07 to 2.22]), and female gender (HR 1.52 [1.11 to 2.07]) were independent predictors. In conclusion, 3.6% of patients with AF developed severe TR over long-term follow-up, with moderate TR, age, previous HF, PeAF, and female gender as independent predictors., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Ventricular tachyarrhythmia is a potentially fatal outcome of cardiac surgery. Abrupt changes in the hemodynamics after surgical correction of valvular heart disease (VHD) can lead to alterations in ventricular repolarization. We compared the difference between temporal changes in repolarization parameters after correction of left-sided VHD., Methods: We retrospectively analyzed the electrograms of patients who underwent surgical correction of isolated VHD between 2006 and 2015 at Asan Medical Center, including mitral stenosis (MS), mitral regurgitation (MR), aortic stenosis (AS), and aortic regurgitation (AR). Ventricular repolarization parameters were measured at pre-specified time intervals after index surgery using a custom-made ECG analysis program. We compared repolarization parameters, including QT and corrected QT intervals, T peak-to-end interval, and corrected T peak-to-end interval., Results: Analysis of 8265 ECGs from 2110 patients (266 MS, 1059 MR, 421 AS, and 364 AR) was performed. Patients with AS were characterized by older age and more comorbidities than other VHDs. The corrected QT interval showed a peak value immediately after surgery and decreased thereafter in the AS groups. However, a gradual increase over 1 month after surgery in AR, MS, and MR groups was observed. The corrected T peak-to-end interval increased in the MS and MR groups and was unchanged in the AS and AR groups., Conclusions: The repolarization parameters of surgery changed dynamically after left-sided valvular surgery. Understanding differential temporal change of repolarization parameters according to the type of VHD would help clinicians avoid fatal arrhythmias related to the repolarization changes., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023. Published by Elsevier Inc.)

Background: The clinical benefits and risks of anticoagulation therapy in patients with chronic kidney disease (CKD) are still inconclusive. We describe the outcomes of patients with atrial fibrillation (AF) after anticoagulation therapy according to differences in creatinine clearance (CrCl). We also aimed to determine the patients who could benefit from anticoagulation therapy., Methods: This is a retrospective observational review of patients with AF who were managed at Asan Medical Center (Seoul, Korea) between January 1, 2006, and December 31, 2018. Patients were categorized into groups according to their baseline CrCl by Cockcroft-Gault equation and their outcomes were evaluated (CKD 1, ≥ 90 mL/min; CKD2, 60-89 mL/min; CKD3, 30-59 mL/min; CKD4, 15-29 mL/min; CKD 5, < 15 mL/min). The primary outcome was NACE (net adverse clinical events), defined as a composite of all-cause mortality, thromboembolic events, and major bleeding., Results: We identified 12,714 consecutive patients with AF (mean 64.6 ± 11.9 years, 65.3% male, mean CHA 2 DS 2 -VASc score 2.4 ± 1.6 points) between 2006 and 2017. In patients receiving anticoagulation therapy (n = 4447, 35.0%), warfarin (N = 3768, 84.7%) was used more frequently than NOACs (N = 673, 15.3%). There was a higher 3-year rate of NACE with renal function deterioration (14.8%, 18.6%, 30.3%, 44.0%, and 48.8% for CKD stages 1-5, respectively).The clinical benefit of anticoagulation therapy was most prominent in patients with CKD 1 (hazard ratio [HR] 0.49, 95% confidence interval [CI] 0.37-0.67), 2 (HR 0.64 CI 0.54-0.76), and 3 (HR 0.64 CI 0.54-0.76), but not in CKD 4 (HR 0.86, CI 0.57-1.28) and 5 (HR 0.81, CI 0.47-1.40). Among patients with CKD, the benefit of anticoagulation therapy was only evident in those with a high risk of embolism (CHA 2 DS 2 -VASc score ≥ 4, HR 0.25, CI 0.08-0.80)., Conclusion: Advanced CKD is associated with a higher risk of NACE. The clinical benefit of anticoagulation therapy was reduced with the increasing CKD stage., (© 2023. The Author(s).)

Background: Evidence and guidelines for Non-vitamin K antagonist oral anticoagulants (NOACs) use when prescribing concurrent rifampin for tuberculosis treatment in patients with non-valvular atrial fibrillation (NVAF) are limited., Methods: Using the Korean National Health Insurance Service database from January 2009 to December 2018, we performed a population-based retrospective cohort study to assess the net adverse clinical events (NACE), a composite of ischemic stroke or systemic embolism and major bleeding, of NOACs compared with warfarin among NVAF patients taking concurrent rifampin administration for tuberculosis treatment. After a propensity matching score (PSM) analysis, Cox proportional hazards regression was performed in matched cohorts to investigate the clinical outcomes., Results: Of the 735 consecutive patients selected, 465 (63.3%) received warfarin and 270 (36.7%) received NOACs. Among 254 pairs of patients after PSM, the crude incidence rate of NACE was 25.6 in NOAC group and 32.8 per 100 person-years in warfarin group. There was no significant difference between NOAC and warfarin use in NACE (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.48-1.14; P = 0.172). Major bleeding was the main driver of NACE, and NOAC use was associated with a statistically significantly lower risk of major bleeding than that with warfarin use (HR, 0.63; 95% CI, 0.40-1.00; P = 0.0499)., Conclusions: In our population-based study, there was no statically significant difference in the occurrence of NACE between NOAC and warfarin use. NOAC use may be associated with a lower risk of major bleeding than that with warfarin use., (© 2023. The Author(s).)

The implantable cardioverter-defibrillator (ICD) is an effective method to prevent sudden cardiac death in high-risk patients. However, the transvenous lead is incompatible with large-area electrophysiological mapping and cannot accommodate selective multichannel precision stimulations. Moreover, it involves high-energy shocks, resulting in pain, myocardial damage, and recurrences of ventricular tachyarrhythmia (VTA). We present a method for VTA treatment based on subthreshold electrical stimulations using a stretchable epicardial multichannel electrode array, which does not disturb the normal contraction or electrical propagation of the ventricle. In rabbit models with myocardial infarction, the infarction was detected by mapping intracardiac electrograms with the stretchable epicardial multichannel electrode array. Then, VTAs could be terminated by sequential electrical stimuli from the epicardial multichannel electrode array beginning with low-energy subthreshold stimulations. Last, we used these subthreshold stimulations to prevent the occurrence of additional VTAs. The proposed protocol using the stretchable epicardial multichannel electrode array provides opportunities toward the development of innovative methods for painless ICD therapy.

Hypertension is an independent risk factor for thromboembolic events in patients with atrial fibrillation (AF). However, the association between blood pressure (BP) control and thromboembolic events remains under-evaluated in patients with AF. We aimed to identify the relation between BP control and the risk of ischemic stroke and systemic embolism in hypertensive patients with AF. Data on 13,712 consecutive patients with AF (9,505 with and 4,207 without hypertension) were retrospectively analyzed. The hypertensive group was divided into quartiles according to the initial BP, linearly interpolated mean BP, variability independent of the mean of the BP, and time in therapeutic range (&lt;130 mm Hg for systolic BP [SBP] and &lt;80 mm Hg for diastolic BP) during follow-up. The primary outcome was ischemic stroke and systemic embolism. The mean follow-up duration of the study population was median 2.7 years (interquartile range 1.1 to 4.9 years), and the median number of BP measurements was 14 (interquartile range 6 to 25) times. Strictly controlled initial and interpolated mean BP and low variability in controlled BP (variability independent of the mean) were associated with a lower risk of ischemic stroke and systemic embolism for both SBP and diastolic BP. A similar risk was observed in patients with strictly controlled SBP (time in therapeutic range under 130 mm Hg &gt;94%) and those without hypertension. In conclusion, continuous and strict maintenance of SBP under 130 mm Hg with low variability at outpatient clinic follow-up reduces the risk of ischemic stroke and systemic embolism in patients with hypertension and AF., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Purpose: Limited data are available on the impact of dronedarone treatment in Asian patients with atrial fibrillation (AF) or atrial flutter (AFL). This post hoc analysis evaluated the efficacy and safety of dronedarone compared with placebo in populations from Asian and non-Asian regions randomized in the ATHENA trial (A Placebo-Controlled, Double-blind, Parallel Arm Trial to Assess the Efficacy of Dronedarone 400 mg BID for the Prevention of CV Hospitalization or Death From Any Cause in Patients With AF/AFL)., Methods: Time to first hospitalization for cardiovascular events or death from any cause (primary outcome) and time to first AF/AFL event recurrence (secondary outcome) were analyzed by Kaplan-Meier curves and Cox proportional hazards regression., Findings: The risk of experiencing the primary composite outcome was significantly lower in the dronedarone-treated patients in both the Asian (hazard ratio = 0.541; 95% CI, 0.320-0.914]) and non-Asian (hazard ratio = 0.768; 95% CI, 0.696-0.848) populations than in the placebo-treated patients. The median time to the first AF/AFL event recurrence was longer in the dronedarone-treated population than in the placebo-treated populations: 183 vs 92 days (P = 0.165) in the Asian population and 534 vs 196 days (P < 0.001) in the non-Asian population. Treatment-emergent adverse events in Asian (81.2% vs 78.4%) and non-Asian (71.4% vs 68.7%) populations and serious treatment-emergent adverse events in Asian (14.3% vs 15.7%) and non-Asian (20.3% vs 21.5%) patients were comparable in patients taking dronedarone compared with those taking placebo., Implication: Efficacy and tolerability of dronedarone were consistent in the Asian population compared with the non-Asian population in the ATHENA trial. These finding may aid Asian health care professionals to select the appropriate first-line treatment for Asian patients with AF/AFL., Competing Interests: Declaration of Interest Changsheng Ma has received honoraria for giving lectures from Bristol-Myers Squibb (BMS), Pfizer, Johnson & Johnson, Boehringer-Ingelheim (BI), Bayer and AstraZeneca. Jiunn-Lee Lin, Rong Bai, Yihong Sun and Gi-Byoung Nam declare no potential conflict of interest. Mattias Wieloch and John Stewart are employees of Sanofi and are shareholders of Sanofi. Jun Zhu has received research grant from Bayer, has acted as a speaker for Bayer, BI, Sanofi and Novartis, and has received payment for travel to and registration for ESC conference from Bayer., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have been shown to lower cardiovascular morbidity and mortality in patients with type 2 diabetes mellitus (T2DM) and high cardiovascular risks. Here, we aimed to evaluate the effect of SGLT2 inhibitors on major adverse cardiovascular events (MACE), a composite of cardiovascular mortality, myocardial infarction, or ischemic stroke and hospitalization for heart failure in patients with T2DM and atrial fibrillation (AF). Using the Korean National Health Insurance Service database, we identified 40,268 patients with T2DM and AF who were newly prescribed oral hypoglycemic drugs (2,977 patients with SGLT2 inhibitors and 37,291 patients without SGLT2 inhibitors) between 2014 and 2018. After 1: 4 propensity score matching, patients who received SGLT2 inhibitors (n = 2,958) and those who did not receive SGLT2 inhibitors (n = 10,691) were enrolled, and followed up until December 31, 2018. During a mean follow-up duration of 2.1 ± 1.4 years, the risk of major adverse cardiovascular events was similar between the 2 groups (hazard ratio [HR] 0.96, 95% confidence interval [CI] 0.76 to 1.21). There were no significant differences between the 2 groups for cardiovascular mortality, myocardial infarction, or ischemic stroke. However, patients who received SGLT2 inhibitors had significantly lower risks of hospitalization for heart failure (HR 0.70, 95% CI 0.53 to 0.93) and all-cause mortality (HR 0.74, 95% CI 0.56 to 0.98) than those who did not receive SGLT2 inhibitors. In conclusion, in this real-world cohort of Asian patients with T2DM and AF, use of SGLT2 inhibitors was associated with a lower risk of hospitalization for heart failure., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Warfarin is the standard anticoagulation therapy for valvular atrial fibrillation (AF); however, new oral anticoagulants have emerged as an alternative. We compared the efficacy and safety of dabigatran with conventional treatment in AF associated with left-sided valvular heart disease (VHD), including mitral stenosis (MS). Patients with AF and left-sided VHD were randomly assigned to receive dabigatran or conventional treatment. The primary end point was the occurrence of clinical stroke or a new brain lesion (silent brain infarct and microbleed) on 1-year follow-up brain magnetic resonance imaging. Patients in the dabigatran group were switched from warfarin (n = 52), antiplatelets alone (n = 5), or no therapy (n = 2) to dabigatran. In the conventional group, 53 used warfarin (including 42 MS patients), and 7 used antiplatelets. No death or clinical stroke event occurred in either group during follow-up. Silent brain infarct and microbleed occurred in 20 and 2 patients in the dabigatran group and 20 and 4 patients in the conventional treatment group. The incidence rate of the primary end point did not significantly differ between groups (34% vs 40%, relative risk 0.87, 95% confidence interval 0.59 to 1.29, p = 0.491). The primary end point rate was similar between groups in 82 patients (40 in the dabigatran group and 42 in the conventional group) with MS (32% vs 34%, relative risk 0.93, 95% confidence interval: 0.57 to 1.50, p = 0.759). In conclusion, primary end point rates after treatment with dabigatran were similar to conventional treatment in patients with significant VHD and AF. New oral anticoagulants could be a reasonable alternative to warfarin in patients with AF and VHD, which should be confirmed in future large-scale studies., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background and Objectives: Atrial tachycardias (ATs) from noncoronary aortic cusp (NCC) uncovered after radiofrequency ablation for atrial fibrillation (AF) are rarely reported. This study was conducted to investigate the prevalence and clinical characteristics of NCC ATs detected during AF ablation and compare their characteristics with de novo NCC ATs without AF., Methods: Consecutive patients who underwent radiofrequency catheter ablation for AF were reviewed from the multicenter AF ablation registry of 11 tertiary hospitals. The clinical and electrophysiological characteristics of NCC AT newly detected during AF ablation were compared with its comparators (de novo NCC AT ablation cases without AF)., Results: Among 10,178 AF cases, including 1,301 redo ablation cases, 8 (0.08%) NCC AT cases were discovered after pulmonary vein isolation (PVI; 0.07% in first ablation and 0.15% in redo ablation cases). All ATs were reproducibly inducible spontaneously or with programmed atrial stimulation without isoproterenol infusion. The P-wave morphological features of tachycardia were variable depending on the case, and most cases exhibited 1:1 atrioventricular conduction. AF recurrence rate after PVI and NCC AT successful ablation was 12.5% (1 of 8). Tachycardia cycle length was shorter than that of 17 de novo ATs from NCC (303 versus 378, p=0.012). No AV block occurred during and after successful AT ablation., Conclusions: Uncommon NCC ATs (0.08% in AF ablation cases) uncovered after PVI, showing different characteristics compared to de-novo NCC ATs, should be suspected irrespective of P-wave morphologies when AT shows broad propagation from the anterior interatrial septum., Competing Interests: The authors have no financial conflicts of interest., (Copyright © 2022. The Korean Society of Cardiology.)

Aims: Use of antiarrhythmic drugs (AADs) in patients with chronic kidney disease (CKD) is challenging owing to issues with renal clearance, drug accumulation, and increased proarrhythmic risks. Because CKD is a common comorbidity in patients with atrial fibrillation/atrial flutter (AF/AFL), it is important to establish the efficacy and safety of AAD treatment in patients with CKD., Methods and Results: Dronedarone efficacy and safety in individuals with AF/AFL and varying renal functionality [estimated glomerular filtration rate (eGFR): ≥60, ≥45 and <60, and <45 mL/min] was investigated in a post hoc analysis of ATHENA (NCT00174785), a randomized, double-blind trial of dronedarone vs. placebo in patients with paroxysmal or persistent AF/AFL plus additional cardiovascular (CV) risk factors. Log-rank testing and Cox regression were used to compare the incidence of endpoints between treatments. Overall, 4588 participants were enrolled from the trial. There was no interaction between treatment group and baseline eGFR assessed as a continuous variable (P = 0.743) for the first CV hospitalization or death from any cause (primary outcome). This outcome was lower with dronedarone vs. placebo across a wide range of renal function. First CV hospitalization and first AF/AFL recurrence were both lower in the two least renally impaired subgroups with dronedarone vs. placebo. Treatment emergent adverse events leading to treatment discontinuation were more frequent with dronedarone vs. placebo and occurred more often in patients with severe renal impairment., Conclusion: Dronedarone is an effective AAD in patients with AF/AFL and CV risk factors across a wide range of renal function., (© The Author(s) 2021. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Background and Objective: Electrocardiogram (ECG) is measured in various ways. The three main ECG measurement methods include resting ECG, Holter monitoring, and treadmill method. In standard ECG measurement methods, multiple electrodes are attached to the limb and chest. Limb and chest leads measure the frontal and sagittal planes of the heart, respectively. In this case, ECG signals are measured briefly up to 10 seconds. To measure ECG signals based on a single lead, wearable devices have been developed that could measure long-term ECG signals daily. ECG signals are vectors in the heart, which is a three-dimensional structure. Therefore, a single-lead measurement lacks detailed information. The objective of this study was to synthesize multiple ECGs from a single-lead ECG using a generative adversarial network (GAN)., Methods: We trained our model with two independent datasets and one combined dataset. For experiment 1, the PTB-XL dataset was used as the training set, and the China dataset was used as the test set. For experiment 2, the China dataset was used as the training set, and the PTB-XL was used as the test set. Optimized GAN models were obtained for each experiment and evaluated., Results: The Fréchet distance (FD) score and mean squared error (MSE) were used for evaluation. The FD and MSE scores for experiments 1 and 2 were 7.237 and 0.024, and 8.055 and 0.011, respectively., Conclusion: We proposed a method to overcome the limitations of modern ECG measurement methods. Low FD and MSE scores not only indicate the possibility but also the similarity between synthesized ECG and reference ECG when compared in ECG paper format. This indicates that the proposed method can be applied to wearable devices that measure single-lead ECG., (Copyright © 2022. Published by Elsevier B.V.)

Background: Anticoagulants are the standard therapy for patients with atrial fibrillation (AF) and antiplatelet therapy for those with coronary artery disease (CAD). However, compelling clinical evidence is still lacking regarding the long-term maintenance strategy with the combination of anticoagulant and antiplatelet drugs in patients with AF and stable CAD., Design: The EPIC-CAD trial is an investigator-initiated, multicenter, open-label randomized trial comparing the safety and efficacy of 2 antithrombotic strategies in patients with high-risk AF (CHA 2 DS 2 -VASc score ≥ 2 points) and stable CAD (≥6 months after revascularization for stable angina or ≥12 months for acute coronary syndrome; or medical therapy alone). Patients (approximately N = 1,038) will be randomly assigned at a 1:1 ratio to (1) monotherapy with edoxaban (a non-vitamin K antagonist oral anticoagulant) or (2) combination therapy with edoxaban plus a single antiplatelet agent. The primary endpoint is the net composite outcome of death from any cause, stroke, systemic embolism, myocardial infarction, unplanned revascularization, and major or clinically relevant nonmajor bleeding at 1 year after randomization., Results: As of December 2021, approximately 901 patients had been randomly enrolled over 2 years at 18 major cardiac centers across South Korea. The completed enrollment is expected at the mid-term of 2022, and the primary results will be available by 2023., Conclusions: EPIC-CAD is a large-scale, multicenter, pragmatic design trial, which will provide valuable clinical insight into edoxaban-based long-term antithrombotic therapy in patients with high-risk AF and stable CAD., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background/aims: The safety of direct oral anticoagulants (DOACs) compared with warfarin in patients with both nonvalvular atrial fibrillation (AF) and clinically confirmed liver cirrhosis (LC) has not been well studied. We compared the risk of a major bleeding event between DOAC and warfarin treatments in this patient population., Methods: A total of 238 cirrhotic patients with AF were retrospectively analyzed. The major bleeding event risk was compared between DOAC- and warfarin-treated groups. The median follow-up duration was 5.6 years., Results: Among the 238 study patients with LC and AF, 128 (53.8%) received DOACs and 110 (46.2%) received warfarin. The mean patient age was 68.8 years, and 78.2% were men. A major bleeding event occurred in 10 and 20 patients in the DOAC and warfarin groups, respectively, most commonly caused by gastrointestinal bleeding (70.0%). The cumulative risk of major bleeding did not differ between the groups by log-rank test (p = 0.12). This finding did not change when using 60 propensity score-matched pairs. A multivariable Cox regression model indicated that the concomitant use of antiplatelet agents (adjusted hazard ratio [aHR], 2.06; 95% confidence interval [CI], 1.00 to 4.30; p = 0.048) and presence of esophageal or gastric varices confirmed by endoscopic examination (aHR, 2.31; 95% CI, 1.03 to 5.17; p = 0.04) were associated with major bleeding in the entire cohort., Conclusion: A major bleeding event risk is not increased by DOAC compared with warfarin treatment. Antiplatelet agent use and varices are independently associated with a higher risk of major bleeding during anticoagulation.

Exposure to ultraviolet (UV) radiation is the main reason behind extrinsic skin aging. Changes due to chronic UV exposure are called photoaging. Natural products are effective ingredients against UV-mediated skin damage. Present study investigated the anti-photoaging properties of  Camellia japonica flowers which possess various bioactivities. To enrich the extracts of C. japonica flowers, pectinase and beta-glucosidase treatment was employed. Anti-photoaging effect was screened using the changes in MMP-1 and collagen levels in UVA-irradiated human HaCaT keratinocytes. The crude extract of C. japonica flowers (CE) was shown to decrease the UVA-induced MMP-1 secretion while attenuating the collagen levels. Pectinase and beta-glucosidase treated CE (ECE) showed increased anti-photoaging effects against UVA-induced changes in MMP-1 and collagen production. Camellenodiol (CMD), a known triterpenoid from C. japonica , isolated as the active ingredient of ECE and its anti-photoaging effect was screened. Results showed that CMD ameliorated the UVA-induced deterioration in collagen levels by suppressing MMP-1 production in transcriptional level. CMD treatment downregulated the phosphorylation of p38, ERK, and JNK MAPKs along their downstream effectors, c-Fos, and c-Jun. In conclusion, enzyme-assisted extraction of C. japonica flowers was suggested to enhance the anti-photoaging properties suggestively through high bioactive content such as CMD., (© 2022 Walter de Gruyter GmbH, Berlin/Boston.)

Background: An association has been identified between mitral valve prolapse (MVP) and sudden cardiac arrest (SCA), and ventricular arrhythmias (VA). This study aimed to elucidate predictive factors for SCA or VA in MVP patients., Methods: MVP patients who underwent cardiac magnetic resonance (CMR) were retrospectively included. Patients with other structural heart disease or causes of aborted SCA were excluded. Clinical characteristics (sex, age, body mass index, histories of diabetes, hypertension, and dyslipidemia) and electrocardiographic (PR interval, QRS duration, corrected QT interval, inverted T wave in the inferior leads, bundle branch block, and atrial fibrillation), echocardiographic [mitral regurgitation grade, prolapsing mitral leaflet, and right ventricular systolic pressure (RVSP)], and CMR [left atrial volume index, both ventricular ejection fractions, both ventricular end-diastolic and systolic volume indexes, prolapse distance, mitral annular disjunction, systolic curling motion, presence of late gadolinium enhancement (LGE), LGE volume and proportion] parameters were analyzed., Results: Of the 85 patients [age, 54.0 (41.0-65.0) years; 46 men], seven experienced SCA or VA. Younger age and wide QRS complex were observed more often in the SCA/VA group than in the no-SCA/VA group. The SCA/VA group exhibited lower RVSP, more systolic curling motion and LGE, greater LGE volume, and higher LGE proportion. The presence of LGE [hazard ratio (HR), 19.8; 95% confidence interval (CI) 2.65-148.15; P = 0.004], LGE volume (HR 1.08; 95% CI 1.02-1.14; P = 0.006) and LGE proportion (HR 1.32; 95% CI 1.08-1.60; P = 0.006) were independently associated with higher risk of SCA or VA in MVP patients together with systolic curling motion in each model., Conclusions: The presence of systolic curling motion, high LGE volume and proportion, and the presence of LGE on CMR were independent predictive factors for SCA or VA in MVP patients., (© 2021. The Author(s).)

Objective: Arrhythmogenic mitral valve prolapse (MVP) is an important cause of sudden cardiac death characterized by fibrosis of the papillary muscles or left ventricle (LV) wall, and an association between late gadolinium enhancement (LGE) of the LV papillary muscles and ventricular arrhythmia in MVP has been reported. However, LGE of the papillary muscles may be observed in other causes of mitral regurgitation, and it is not limited to patients with MVP. This study was to evaluate the association of LGE of the LV papillary muscles or ventricular wall on cardiac magnetic resonance imaging (CMR) and ventricular arrhythmia in patients with mitral regurgitation., Materials and Methods: This study included 88 patients (mean age ± standard deviation, 58.3 ± 12.0 years; male, 42%) with mitral regurgitation who underwent CMR. They were allocated to the MVP (n = 43) and non-MVP (n = 45) groups, and their LGE images on CMR, clinical characteristics, echocardiographic findings, and presence of arrhythmia were compared., Results: LV myocardial wall enhancement was more frequent in the MVP group than in the non-MVP group (28% vs. 11%, p = 0.046). Papillary muscle enhancement was observed in 7 (7.9%) patients. Of the 43 patients with MVP, 15 (34.8%) showed LGE in the papillary muscles or LV myocardium, including 12 (27.9%) with LV myocardial wall enhancement and 4 (9.3%) with papillary muscle enhancement. One patient with bilateral diffuse papillary muscle enhancement experienced sudden cardiac arrest due to ventricular fibrillation. Univariable logistic regression analysis showed that high systolic blood pressure (BP; odds ratio [OR], 1.05; 95% confidence interval [CI], 1.01-1.09; p = 0.027) and ventricular arrhythmia (OR, 6.84; 95% CI, 1.29-36.19; p = 0.024) were significantly associated with LGE of the papillary muscles., Conclusion: LGE of the papillary muscles was present not only in patients with MVP, but also in patients with other etiologies of mitral regurgitation, and it was associated with high systolic BP and ventricular arrhythmia. Papillary muscle enhancement on CMR should not be overlooked., Competing Interests: The authors have no potential conflicts of interest to disclose., (Copyright © 2021 The Korean Society of Radiology.)

Background: Brugada syndrome (BrS) is associated with mutations in the cardiac sodium channel gene, SCN5A. However, genetic studies of patients with BrS with arrhythmic events have been limited. We sought to compare various clinical, ECG, and electrophysiological parameters according to SCN5A genotype in a large cohort of BrS probands with first arrhythmic event., Methods: Survey on Arrhythmic Events in Brugada Syndrome is a survey of 10 Western and 4 Asian countries, gathering 678 patients with BrS with first arrhythmic event. Only probands were included, and SCN5A genotype adjudicated. Patients without appropriate genetic data were excluded. Associations of genotype with clinical features were analyzed., Results: The study group comprised 392 probands: 92 (23.5%) SCN5A+ (44 pathogenic/likely pathogenic [P/LP] and 48 variants of unknown significance) and 300 (76.5%) SCN5A-. SCN5A missense variants and the patients hosting them were similar regardless of adjudication. A higher proportion of patients with P/LP were pediatric (<16 years) compared with SCN5A- (11.4% versus 3%, P =0.023). The proportion of females was higher among patients with P/LP compared with SCN5A - (18.2% versus 6.3%, P =0.013). P/LP probands were more likely to have a family history of sudden cardiac death compared with SCN5A - (41.9% versus 16.8%, P <0.001). A higher proportion of patients with P/LP were White compared with SCN5A- (87.5% versus 47%, P <0.001). Ethnicity (odds ratio, 5.41 [2.8-11.19], P <0.001) and family history of sudden cardiac death (odds ratio, 2.73 [1.28-5.82], P =0.009) were independent variables associated with P/LP genotype following logistic regression., Conclusions: The genetic basis of BrS has a complex relationship with gender, ethnicity, and age. Probands hosting a P/LP variant tended to experience their first arrhythmic event at a younger age and to have events triggered by fever compared with patients with SCN5A- . In addition, they were more likely to be White and to have family history of sudden cardiac death. Among females, a P/LP variant suggests an increased risk of being symptomatic. This association should be further studied on an ethnically specific basis in large prospectively collected international cohorts.

Background/aims: Atrial fibrillation (AF)-related stroke accounts for 20% of ischemic strokes. Rivaroxaban use in AF patients for preventing stroke and systemic embolism was approved in 2013 in Korea. This study was to investigate the safety and effectiveness of rivaroxaban use in Korean patients with non-valvular AF in a real-world setting., Methods: This was an analysis of the Korean patients in Xarelto for Prevention of Stroke in Patients with Atrial Fibrillation in Asia-Pacific (XANAP), which was a prospective, observational cohort study including patients with non-valvular AF starting rivaroxaban treatment to prevent stroke or non-central nervous system systemic embolism (non-CNS SE), conducted in 10 Asian countries., Results: A total of 844 patients were enrolled in the Korean portion of the XANAP study. In XANAP Korea, the mean age was 70.1 years and 62.6% were males. The mean CHADS2 score was 2.5 and the mean CHA2DS2-VASc score was 3.8. 47% of the patients had experienced prior stroke or non-CNS SE or transient ischemic attack. 73.6% of the patients had CHADS2 score ≥ 2. Incidence proportions of 0.8% of the patients (1.1 per 100 patient-years) developed adjudicated treatment-emergent major bleeding. Death was observed in 1.2% of the patients. The incidence of non-major bleeding as well as thromboembolic event were 8.4% (11.6 per 100 patient-years) and 1.5% (2.0 per 100 patient-years), respectively., Conclusion: This study reaffirmed the consistent safety profile of rivaroxaban. We found consistent results with overall XANAP population for rivaroxaban in terms of safety in non-valvular AF patients for the prevention of stroke and non-CNS SE.

Abstract: Transcatheter aortic valve replacement (TAVR) is a standard treatment indicated for severe aortic stenosis in high-risk patients. The objective of this study was to evaluate the incidence of pacemaker dependency after permanent pacemaker implantation (PPI) following TAVR or surgical aortic valve replacement (SAVR) and the risk of mortality at a tertiary center in Korea.In this retrospective study conducted at a single tertiary center, clinical outcomes related to pacemaker dependency were evaluated for patients implanted with pacemakers after TAVR from January 2012 to November 2018 and post-SAVR from January 2005 to May 2015. Investigators reviewed patients' electrocardiograms and baseline rhythms as well as conduction abnormalities. Pacemaker dependency was defined as a ventricular pacing rate > 90% with an intrinsic rate of <40 bpm during interrogation.Of 511 patients who underwent TAVR for severe AS, 37(7.3%) underwent PPI after a median duration of 6 (3-7) days, whereas pacemakers were implanted after a median interval of 13 (8-28) days post-SAVR in 10 of 663 patients (P < .001). Pacemaker dependency was observed in 36 (97.3%) patients during 7 days immediately post-TAVR and in 25 (64.9%) patients between 8 and 180 days post-TAVR. Pacemaker dependency occurred after 180 days in 17 (50%) patients with TAVR and in 4 (44.4%) patients with SAVR. Twelve (41.4%) patients were pacemaker-dependent after 365 days post-TAVR.Pacemaker dependency did not differ at 6 months after TAVR vs SAVR. In patients undergoing post-TAVR PPI, 58.6% were not pacemaker-dependent at 1 year after the TAVR procedure., Competing Interests: The authors have no funding and conflicts of interests to disclose., (Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: The left lateral ridge (LLR) is an important structure for ablation of atrial fibrillation (AF). This study assessed how the LLR shape is associated with the long-term outcomes of AF ablation and investigated the relationship with radiofrequency (RF) lesion formation., Methods and Results: Clinical study - we assessed multi-detector computed tomography (MDCT) images in 247 patients who underwent AF ablation. Patients were classified into two groups according to the shape of the LLR: Narrow LLR group (n = 116; 47%) and Wide LLR group (n = 131; 53%). After a follow-up period 475 ± 245 days, the AF-free rate was significantly higher in the wide LLR than Narrow LLR group (83.2% vs. 62.9%, p = 0.0004). A multivariate analysis showed that the shape of the LLR was an independent predictor of AF recurrence after ablation (hazard ratio 2.58; 95% confidential interval = 1.48-4.51, p = 0.001). Experimental study - Two types of the ridge models were made with porcine atrial tissues: "Narrow ridge(4.2 ± 0.9 mm)" and "Wide ridge(9.7 ± 1.8 mm)" RF ablation was performed on each ridge model using a contact force (CF)-sensing catheter. The mean CF and the RF lesion volume of the narrow ridge were significantly less than those of the wide ridge model (5.42 ± 3.13 g vs. 10.37 ± 3.98 g, p = 0.001; 19.8 ± 9.9 mm 3 vs. 44.2 ± 13.6 mm 3 , p < 0.001, respectively)., Conclusions: AF recurrence after ablation was more frequent in patients with a narrow LLR. LLR shape as assessed using MDCT is associated with long-term outcomes after AF ablation. CF and lesion formation data using the porcine atrial tissue model support our clinical results., Competing Interests: Declaration of Competing Interest The authors have no financial conflicts of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background Postoperative atrial fibrillation (POAF) is common after cardiac surgery, but little is known about its incidence and natural course after noncardiac surgery. We evaluated the natural course and clinical impact of POAF and the long-term impact of anticoagulation therapy in patients without a history of atrial fibrillation (AF) undergoing noncardiac surgery. Methods and Results We retrospectively analyzed the database of Asan Medical Center (Seoul, Korea) to identify patients who developed new-onset POAF after undergoing noncardiac surgery between January 2006 and January 2016. The main outcomes were AF recurrence, thromboembolic event, and major bleeding during follow-up. Of 322 688 patients who underwent noncardiac surgery, 315 patients (mean age, 66.4 years; 64.4% male) had new-onset POAF with regular rhythm monitoring after discharge. AF recurred in 53 (16.8%) during 2 years of follow-up. Hypertension (hazard ratio, 2.12; P =0.02), moderate-to-severe left atrial enlargement (hazard ratio, 2.33; P =0.007) were independently associated with recurrence. Patients with recurrent AF had higher risks of thromboembolic events (11.2% versus 0.8%; P <0.001) and major bleeding (26.9% versus 4.1%; P <0.001) than those without recurrence. Patients with recurrent AF and without anticoagulation were especially predisposed to thromboembolic events ( P <0.001). Overall, anticoagulation therapy was not significantly associated with thromboembolic events (1.4% versus 2.5%, P =0.95). Conclusions AF recurred in 16.8% of patients with POAF after noncardiac surgery. AF recurrence was associated with higher risks of adverse clinical outcomes. Considering the high risk of anticoagulation-related bleeding, the benefits of routine anticoagulation should be carefully weighed in this population. Active surveillance for AF recurrence is warranted.

The current thromboembolic risk stratification of non-valvular atrial fibrillation (NVAF) does not include parameters from transthoracic echocardiography (TTE). We hypothesized that left atrial enlargement (LAE) on TTE could discriminate who require anticoagulation therapy among NVAF patients with low/borderline clinical embolic risk. This single-center cohort study included 6,602 patients with NVAF (median age, 56 years, 70.0% male) with a low to borderline clinical embolic risk (CHA 2 DS 2 -VASc score: 0 to 1 in males, 1 to 2 in females). LAE was classified as mild (≥41 mm in males; ≥39 mm in females) or moderate-severe (≥47 mm in males; ≥43 mm in females). The main study outcome was thromboembolic event (ischemic stroke and systemic embolism). Mild and moderate-severe LAE was diagnosed in 26.1% and 32.9% of the cohort, respectively. The patients with moderate-severe LAE showed a higher prevalence of baseline comorbidities and valvular heart disease and had a higher incidence of thromboembolic events than patients with mild or no LAE at 2 years of follow-up (2.5% vs 1.3% vs 1.1%, respectively, p < 0.001). After multivariable adjustment, patients with moderate-severe LAE were at a higher risk of thromboembolic event (hazard ratio, 2.54; 95% CI, 1.65 to 3.90; p < 0.001) compared to those with no LAE. This result persisted in a subgroup analysis of anticoagulant-naïve patients. The rate of thromboembolic events in patients with low clinical embolic risk and moderate-severe LAE was not different to those with high clinical embolic risk without LAE. In conclusion, Moderate-severe LAE on TTE was a significant predictor of thromboembolic events in NVAF patients at low/borderline clinical embolic risk., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Differentiation of supraventricular tachycardia (SVT) with a right bundle branch block (RBBB) pattern from ventricular tachycardia (VT) is difficult, particularly when the R/S ratio in lead V 6 is below 1.0., Objective: We sought to investigate the electrocardiographic criteria for distinguishing between these arrhythmias., Methods: We investigated electrocardiographic parameters from 111 consecutive patients who had RBBB pattern wide QRS complex tachycardia with a reversed R/S ratio in lead V 6 (72 VTs, 39 SVTs). Diagnostic criteria from the previous algorithms were compared with our new criterion, the RS/QRS ratio, which was defined as the ratio of the interval from the onset of the QRS complex to the nadir of the S wave, divided by the QRS width in lead V 6 . The RS/QRS ratio was further tested in a prospective population (31 fascicular VTs, 29 SVTs)., Results: The diagnostic accuracy of previous criteria (Brugada algorithm, Vereckei algorithm, and R-wave peak time criterion) was only modest. However, the RS/QRS ratio in lead V 6 was significantly lower in SVT than in VT (0.36 ± 0.04 vs 0.50 ± 0.08; P < .001). A cutoff value of the RS/QRS ratio >0.41 differentiated VT from SVT with a high diagnostic accuracy (sensitivity 97.2%; specificity 89.7%). When tested in a prospective population with fascicular VT, the diagnostic accuracy of the criteria was maintained (sensitivity 90.3%; specificity 86.2%)., Conclusion: The RS/QRS ratio >0.41 in lead V 6 is a simple and reliable index for distinguishing VT from SVT in RBBB pattern wide QRS complex tachycardia with a reversed R/S complex in lead V 6 . This criterion was particularly useful for the differential diagnosis of fascicular VT from RBBB pattern SVT., (Copyright © 2020 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background and Objectives: Data regarding the safety of atrial fibrillation (AF) ablation using high-power (50 W) radiofrequency (RF) energy in Asian populations are limited. This study was conducted to evaluate the incidence and pattern of esophageal injury after high-power AF ablation in an Asian cohort., Methods: We searched the prospective AF ablation registry to identify patients who underwent AF ablation with 50 W RF energy using the smart touch surround flow catheter (Biosense Webster, Diamond Bar, CA, USA). Visitag™ (Biosense Webster) was used for lesion annotation with predefined settings of catheter stability (3 mm for 5 seconds) and minimum contact force (50% of time >5 g). All patients underwent upper gastrointestinal endoscopy at 1 or 3 days after the ablation., Results: A total of 159 patients (mean age: 63±9 years, male: 69%, paroxysmal AF: 45.3%, persistent AF: 27.7%, long-standing persistent AF: 27.0%) were analyzed. Initially, 26 patients underwent pulmonary vein isolation with 50 W for 5 seconds at each point. The remaining 133 patients underwent prolonged RF duration (anterior 10 seconds and posterior 6 seconds). The incidence rates of esophageal erythema/erosion and superficial ulceration were 1.3% for each type of the lesion. Food stasis, a suggestive finding of gastroparesis, was observed in 25 (15.7%) patients. There were no cases of cardiac tamponade, stroke, or death., Conclusions: In Asian patients, AF ablations using 50 W resulted in very low rates of mild esophageal complications., Competing Interests: The authors have no financial conflicts of interest., (Copyright © 2021. The Korean Society of Cardiology.)

Background Severe conduction delay and inter/intra-atrial dissociation may occur in patients who undergo an extensive catheter ablation or a maze procedure for atrial tachyarrhythmia. We report a series of patients with inter/intra-atrial dissociation that mimicked complete atrioventricular block or ventricular tachycardia. Methods and Results We retrospectively reviewed the medical records of 7 patients who were referred for the evaluation of atrioventricular block (patients 1-6) or ventricular tachycardia (patient 7) that occurred after biatrial maze procedure and valvular surgery. During the electrophysiologic study, slow atrial or junctional escape rhythm dissociated from isolated atrial activity mimicked complete atrioventricular blocks. Intra-atrial dissociation of the right atrium or left atrium was observed. Atrioventricular nodal conduction from the nondissociated atrium to the ventricle was preserved in all patients, while the conduction from the dissociated atrium was blocked. In patient 7, the pacing of the ventricle by tracking of atrial tachycardia from the nondissociated left atrium/coronary sinus mimicked ventricular tachycardia during pacemaker interrogation. A total of 5 patients received new permanent pacemaker implantations during the index hospitalization for the surgery (n=2) or as a deferred procedure (n=3) according to the treatment for sick sinus syndrome. Conclusions Pseudo-atrioventricular block or pseudo-ventricular tachycardia may occur because of inter/intra-atrial dissociation after a maze procedure. The selection of patients for permanent pacemaker implantation should be determined based on the patient's symptoms and the status of the escape pacemaker and not on the apparent atrioventricular block. Proper diagnosis is important to avoid unnecessary implantation of a pacemaker or a defibrillator.

Background and Objectives: Pacemaker (PM) implantation is a well-accepted treatment option for patients with paroxysmal atrial fibrillation (AF) and related tachycardia-bradycardia syndrome (TBS). Data on the long-term clinical outcomes after radiofrequency catheter ablation (RFCA) or PM implantation are sparse., Methods: The medical records of 217 patients with TBS were retrospectively assessed. Outcomes in patients who underwent RFCA (n=108, 49.8%) were compared to those with PM implantation (n=109, 50.2%). The clinical outcomes were sinus rhythm maintenance, conversion to persistent AF, additional procedure or crossover, and the composite of cardiovascular hospitalization and death., Results: During the follow-up period (mean 3.5±2.0 years), the RFCA group, compared to the PM group, showed better sinus rhythm maintenance (adjusted hazard ratio [aHR], 0.27; 95% confidence interval [CI], 0.15-0.46; p=0.002) and less progression to persistent AF (aHR, 0.20; 95% CI, 0.06-0.63; p=0.006). Additional procedure or crossover did not differ significantly between the groups (aHR, 2.07; 95% CI, 0.71-6.06; p=0.185 and aHR, 0.69; 95% CI, 10.8-2.67; p=0.590, respectively). Most RFCA patients (92.6%) did not require pacemaker implantation during long term follow-up period (>3.5 years). The composite endpoint of cardiovascular rehospitalization and death was not significantly different between the groups (aHR, 0.92; 95% CI, 0.50-1.66; p=0.769)., Conclusions: RFCA is an effective alternative to PM implantation in patients with TBS. In these patients, successful RF ablation of AF is related to a higher rate of sinus rhythm maintenance compared to PM implantation, and the composite outcome of cardiovascular rehospitalization and death is similar., Competing Interests: The authors have no financial conflicts of interest., (Copyright © 2020. The Korean Society of Cardiology.)

Background: The clinical implications of pericardial effusion (PE) after catheter ablation for atrial fibrillation (AF) are not well understood. We evaluated the association between newly developed PE after pulmonary vein isolation (PVI) for paroxysmal AF and arrhythmic recurrence., Methods: From a prospective AF ablation registry, 184 patients (mean age 59 ± 10 years, 65% male) who underwent first-time PV isolation using a smart touch surround flow catheter (Biosense Webster, Diamond Bar, CA) were analyzed. Postablation transthoracic echocardiography (TTE) was performed within 1-3 days after ablation, and the occurrence of PE was assessed., Results: PE developed in 91 patients (49.5%), and most were of minimal severity (minimal, 93.4%; mild, 6.6%). Patients with PE had significantly lower body mass index and underwent cavotricuspid isthmus ablation more frequently. Early arrhythmic recurrence (EAR) (within 3 months) was observed in 28.8% of patients and was not different according to the PE development (PE [+]: 29.7% vs PE [-]: 28.0%; P = .80). During a median follow-up of 696 days, the cumulative rate of the late arrhythmic recurrence (LAR) (after 3 months) was 36.4%, and there was no difference between groups (PE [+]: 36.7% vs PE [-]: 35.1%; P = .988). The only predictor of LAR was EAR, and no echocardiographic parameters showed a significant correlation with LAR., Conclusions: Minimal or mild PE after PVI for paroxysmal AF is a frequent echocardiographic finding, and it had no significant association with AF recurrence. Routine TTE after AF ablation has no clinical implication., (© 2020 Wiley Periodicals LLC.)

Debulking of left ventricular septal mass is typically accomplished using surgical myectomy, which is morbid, or using transcoronary alcohol septal ablation, which can result in geographic miss and occasional catastrophic nontarget coronary injury. The authors developed and tested operational parameters in vitro and vivo for a device to accomplish transvenous intraseptal radiofrequency ablation to reduce ventricular septal mass using a technique derived from mitral cerclage, which the authors call cerclage ablation . Cerclage ablation appeared feasible in vitro and safe and effective in vivo. Cerclage ablation is an attractive new approach to debulk the interventricular septum in obstructive hypertrophic cardiomyopathy. These data support clinical investigation., Competing Interests: This study was supported by Research and Development grant S2773417 from the Korean Ministry of Small and Medium Enterprise and Startups. Tau-PNU Medical provided the prototype ablation catheters. Dr. J.-W. Park is a medical consultant for Tau-PNU Medical. Drs. J.-H. Kim and Nam are coinventors on patents for devices for mitral loop cerclage ablation. Dr. J.-H Kim is a stockholder of Tau-PNU Medical. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (© 2020 The Authors.)

Background: This study investigated 12-lead electrocardiogram (ECG) predictors associated with atrial fibrillation (AF) or flutter (AFL), specifically whether ventricular repolarization abnormalities in surface ECG (i.e., non-specific ST-T abnormalities [NSSTTA], QT prolongation, early repolarization [ER]) were associated with the development of AF or AFL., Methods and results: This study included 16,793 ambulatory Koreans (mean age 48.2 years, 62.3% male) who underwent medical check-ups at Asan Medical Center in 2002 (NSSTTA, n=1,037 [6.2%]; ER, n=1,493 [8.9%]). The primary outcome was the incidence of ECG-documented AF or AFL. During follow-up, new-onset AF or AFL was documented in 334 subjects (2.0%). The incidence of AF or AFL at the 10-year follow-up was higher in patients with than without NSSTTA (3.5% vs. 1.6%; hazard ratio [HR] 1.79, 95% confidence interval [CI] 1.28-2.50). The QT interval was associated with a higher risk of AF or AFL (HR 1.12 [95% CI 1.07-1.17] per 10 ms), and the risk was even higher in patients with multiple-region NSSTTA (HR 2.30; 95% CI 1.64-3.21) and NSSTTA with QT prolongation (HR 4.06; 95% CI 2.14-7.69). ER was not associated with a higher risk of AF or AFL (HR 1.02; 95% CI 0.71-1.46)., Conclusions: NSSTTA and QT prolongation, but not ER, were associated with a higher risk of future AF or AFL in a general ambulatory population after adjusting for parameters of atrial depolarization.

Competing Interests: None declared.

With safety concerns about increasing bleeding, off-label underdosing of non-vitamin K antagonist anticoagulants (NOACs) is common in East Asian patients with atrial fibrillation (AF). We tried to investigate the pattern of NOAC underdosing and associated clinical outcomes in patients with AF who are indicated for standard dosing. Using the Korean National Health Insurance Service database, we evaluated 16,568 patients with a new prescription of NOAC who are indicated for standard NOAC dosing and compared 4,536 patients with warfarin with respect to thromboembolic events (ischemic stroke or systemic embolization), all-cause mortality and major bleeding. Of the 16,568 patients indicated for standard NOAC dosing, 8,549 (51.9%) received off-label underdosing (50.6% rivaroxaban, 53.0% apixaban). During a median follow up of 15.0 months, as compared with warfarin, underdosing of rivaroxaban was associated with lower risks of major thromboembolic events (hazard ratio [HR]: 0.53; 95% confidence interval [CI]: 0.41 to 0.69) and all-cause mortality (HR 0.57, 95% CI: 0.41 to 0.82), and a similar risk of major bleeding (HR 1.10, 95% CI: 0.82 to 1.46). However, underdosing of apixaban was associated with similar risks of major thromboembolic events (HR: 0.90; 95% CI: 0.70 to 1.16), all-cause mortality (HR 0.94, 95 CI: 0.71 to 1.24) and major bleeding (HR 0.84, 95% CI: 0.61 to 1.17). In conclusion, in this Korean population with AF who are indicated for standard NOAC dosing, off-label underdosing is common and its clinical benefit over warfarin was inconsistent according to types of NOAC. Notably, apixaban underdosing provides no benefit in effectiveness compared with warfarin., (Copyright © 2020 Elsevier Inc. All rights reserved.)