Prevalence of atrial fibrillation in the general population of Japan: an analysis based on periodic health examination

Ablation catheter-induced mechanical deformation in myocardium: computer modeling and ex vivo experiments

Cardiac catheter ablation requires an adequate contact between myocardium and catheter tip. Our aim was to quantify the relationship between the contact force (CF) and the resulting mechanical deformation induced by the catheter tip using an ex vivo model and computational modeling. The catheter tip was inserted perpendicularly into porcine heart samples. CF values ranged from 10 to 80 g. The computer model was built to simulate the same experimental conditions, and it considered a 3-parameter Mooney-Rivlin model based on hyper-elastic material. We found a strong correlation between the CF and insertion depth (ID) (R2 = 0.96, P < 0.001), from 0.7 ± 0.3 mm at 10 g to 6.9 ± 0.1 mm at 80 g. Since the surface deformation was asymmetrical, two transversal diameters (minor and major) were identified. Both diameters were strongly correlated with CF (R2 ≥ 0.95), from 4.0 ± 0.4 mm at 20 g to 10.3 ± 0.0 mm at 80 g (minor), and from 6.4 ± 0.7 mm at 20 g to 16.7 ± 0.1 mm at 80 g (major). An optimal fit between computer and experimental results was achieved, with a prediction error of 0.74 and 0.86 mm for insertion depth and mean surface diameter, respectively.

Prevalence of Atrial Fibrillation in Semiurban Nepal: Result From a Community-Based Cross-Sectional Screening

Background: Atrial fibrillation (AF) is a common morbid arrhythmia that can cause thromboembolic events such as stroke. Despite advancements in diagnostic technologies, a significant number of AF patients may remain undetected and undiagnosed, and these asymptomatic patients possess sufficient risk of cardioembolic stroke. Identifying such patients through appropriate screening techniques and timely initiation of systemic anticoagulation therapy is essential to prevent such life-threatening complications. Objectives: The objectives of this study encompass screening of AF among residents of the Dhulikhel Municipality and identifying its prevalence, along with evaluation of stroke risk and use of antithrombotic therapy in patients confirmed with AF. Methods: All residents of four wards of Dhulikhel Municipality, aged 50 years and above (n = 2048), underwent one-time electrocardiogram (ECG) screening using a portable 12-lead ECG machine. The cardiologist checked the cardiogram, and suspected AF cases were referred to the hospital for further evaluation and appropriate management. They were followed up to find out information on disease confirmation and management. Results: Out of 2048 participants, AF was detected in 16 participants, resulting in an overall prevalence of 0.78% (CI 0.4%-1.3%). The prevalence of AF was highest (2.98%) in population aged 80 years and above. Among individuals with AF, the median age was 71.5 (66.3-79.5) years, 50.0% were male and 75.0% had high stroke risk as indicated by a CHA2DS2-VASc score ≥ 2. Among these patients, only 41.66% were treated with oral anticoagulants (OACs), while 58.34% were treated either with single or dual antiplatelet therapy (DAPT). Conclusion: This study provided important insight into the prevalence of AF at the community level. Many AF patients were at high risk of stroke, but the OAC use was less than 50%. Screening of AF needs to be carried out on a larger scale in Nepal for early detection and timely management of the disease.

Direct Comparison of the Effectiveness and Safety Among Direct Oral Anticoagulants and Warfarin in Japanese Patients: Nationwide Cohort Study in Japan

Direct oral anticoagulant drugs (DOACs) are available in addition to warfarin for the treatment of patients with non-valvular atrial fibrillation (NVAF). Anticoagulants are useful for practical pharmacotherapy in Asian populations, but their responses are different from those in Caucasian populations. Therefore, we aimed to identify the most useful anticoagulant using a nationwide insurance claims database in Japan. We extracted information on patients with NVAF treated with DOACs or warfarin for the first time between September 2015 and February 2018 to conduct a retrospective observational cohort study using the claims database of Japan. We calculated hazard ratios (HR) of effectiveness and safety endpoints among DOACs or warfarin after adjusting for backgrounds by propensity scores (inverse probability weighting). Using negative control outcomes, we considered renal function as an unmeasured confounding factor. After adjusting for their backgrounds, patients treated with DOACs showed higher effectiveness endpoints (stroke or systemic embolism) than those treated with warfarin (HR; 0.72-0.81) and higher safety in terms of safety end points (clinically significant bleeding) (HR; 0.80-0.88). The net clinical benefit, which reflects the actual clinical usefulness, indicates the advantages of DOACs over warfarin (HR; 0.75-0.82). Dabigatran had lower usefulness than edoxaban and rivaroxaban in Japanese patients treated with NVAF, even after considering the unmeasured confounding factor of kidney function. Based on practical clinical data, edoxaban and rivaroxaban were the most useful anticoagulants in Japanese patients with NVAF.

Oral anticoagulation in patients with hypertrophic cardiomyopathy and non-valvular atrial fibrillation in Japan

AIMS

There are limited data to support direct oral anticoagulant (DOAC) use in patients with hypertrophic cardiomyopathy (HCM) and non-valvular atrial fibrillation (NVAF). The current study investigated the safety and effectiveness of DOACs versus warfarin in patients in Japan.

METHODS

This retrospective observational study assessed a Japanese cohort of patients diagnosed with HCM and NVAF between July 2011 and June 2021 using a Japanese claims database. Propensity score (PS) matching (2:1 DOAC:warfarin) using the nearest-neighbour method was applied to balance demographic and clinical characteristics between treatment groups. The primary outcomes were the risk of major bleeding and any bleeding (major or minor). Secondary outcomes included describing baseline demographic and clinical characteristics and the risk of stroke/systemic embolism (SE).

RESULTS

After PS matching, 2955 DOAC- and 1603 warfarin-treated patients were assessed. The mean [standard deviation (SD)] age in the DOAC and warfarin groups was 74.8 (10.5) and 75.3 (10.2) years, respectively. The majority of patients were male (DOAC, 58.8%; warfarin, 59.6%), had comorbidities (DOAC, 97.5%; warfarin, 96.6%), and were treated with β-blockers (DOAC, 62.5%; warfarin, 62.3%). The risk of major and any bleeding was similar across cohorts [hazard ratio (HR), 0.80; 95% confidence interval (CI), 0.50-1.27; P = 0.336 and HR, 0.93; 95% CI, 0.78-1.11; P = 0.420] while the risk of stroke/SE was lower among patients treated with DOACs (HR, 0.67; 95% CI, 0.47-0.96; P = 0.027). Factors associated with an increased risk of major bleeding included prior bleeding (HR, 1.97; 95% CI, 1.22-3.17) and chronic kidney disease (HR, 1.87; 95% CI, 1.10-3.18). An increased risk of stroke/SE was associated with prior ischaemic stroke (HR, 2.97; 95% CI, 2.05-4.29), peripheral arterial disease (HR, 1.88; 95% CI, 1.22-2.88) and chronic kidney disease (HR, 1.87; 95% CI, 1.24-2.83).

CONCLUSIONS

DOAC-treated patients had a lower risk of stroke/SE and a comparable risk of bleeding compared with warfarin-treated patients. Prior stroke was shown to augment stroke risk by approximately three-fold. This large real-world study suggests that patients diagnosed with HCM and NVAF can be safely and effectively treated with DOACs in Japan.

Association of varicose veins with incidence risk of atrial fibrillation: a population-based cohort study

BACKGROUND

Varicose veins (VV) were once considered benign and common ailments; however, recent research suggests a potential link between VV and cardiovascular diseases or mortality. VV share common risk factors and pathophysiology with cardiovascular disease, potentially influencing the vascular system. Therefore, the authors aimed to investigate the association between VV and the incidence risk of atrial fibrillation (AF) using a population-based cohort.

METHODS

Our retrospective cohort study included 2 680 971 individuals who underwent examination through the Korean National Health Screening Service from 2010 to 2011. VV was defined by two or more claims with the International Classification of Diseases 10th Revision diagnostic codes: I83.0, I83.1, I83.2 (VV of lower extremities with ulcer or inflammation, severe VV), and I83.9 (asymptomatic VV of lower extremities, mild VV). The 1:3 propensity score matching (PSM) was used to assess the risk of newly developed AF, identified via insurance claims coded as I48.

RESULTS

The mean age of all participants was 48.5±14.2 years, with 51.4% being male. Among the population, 24 557 (0.91%) had VV, including 3684 (0.14%) of severe VV and 20 873 (0.77%) of mild VV. During a median follow-up of 10.06 years, 24 557 (0.92%) cases of AF occurred. Participants with VV exhibited an increased incidence risk of AF compared to those without it before (HR: 1.13, 95% CI: 1.06-1.21, P <0.001) and after PSM (HR: 1.17, 95% CI: 1.08-1.27, P <0.001). This positive association was consistently observed in severe VV both before (HR: 1.19, 95% CI [1.09-1.28], P =0.002) and after PSM (HR: 1.20, 95% CI [1.10-1.30], P =0.003) and mild VV also before (HR: 1.10, 95% CI [1.04-1.16], P =0.003) and after PSM (HR: 1.13, 95% CI [1.03-1.-20], P <0.001).

CONCLUSIONS

These findings suggest that VV may be associated with an increased risk of AF. Hence, the presence of VV should be considered as an association factor for AF occurrence.

Patient Outcomes in Very Elderly Patients With Non-Valvular Atrial Fibrillation - ANAFIE Registry

Background

The All Nippon Atrial Fibrillation In the Elderly Registry provides real-world insights into non-valvular atrial fibrillation (NVAF) in >30,000 elderly Japanese patients (aged ≥75 years), including >2,000 nonagenarians. We aimed to investigate outcomes in these patients by age and oral anticoagulant (OAC) type.

Methods and Results

This prospective, multicenter, observational, cohort, 2-year follow-up study included elderly patients with NVAF who were able to attend hospital visits. The incidences of stroke/systemic embolic events (SEE), major bleeding, intracranial hemorrhage (ICH), cardiovascular death, all-cause death, and major adverse cardiovascular or neurological events (MACNE) were evaluated by age. Incidence rates increased significantly with age. Stroke/SEE, major bleeding, and ICH incidences plateaued in patients aged ≥90 years. Direct OACs (DOACs) yielded a numerically lower event incidence vs. warfarin in all age groups and endpoints, except for major bleeding in patients aged ≥90 years. DOACs (vs. warfarin) were significantly associated with a lower risk of stroke/SEE, major bleeding, and ICH in the ≥80-<85 years group, and reduced cardiovascular and all-cause death in the ≥75-<80 years group. In the ≥90 years subgroup, major bleeding history was a risk factor for all-cause death.

Conclusions

Although DOAC vs. warfarin offers potential benefits for stroke prevention, limitations occurred in reducing major bleeding among those aged ≥90 years, indicating a potential benefit of very-low-dose DOAC for this demographic.

Stent-retriever characteristics and strategies associated with recanalization in thrombectomy for acute ischemic stroke

INTRODUCTION

Predictive factors for successful reperfusion in mechanical thrombectomy for acute ischemic stroke, and especially technical factors, remain controversial. We investigated various techniques for better angiographic outcomes.

METHODS

In this retrospective study, acute ischemic stroke patients with large vessel occlusion treated with mechanical thrombectomy with combined technique were included. Scoring of the reperfusion grade for each attempt was conducted, and each attempt was divided into two groups based on successful reperfusion, which was defined using the presence or absence of modified thrombolysis in cerebral infarction 2b-3. The following characteristics were evaluated: the choice of stent-retriever, its length, occlusion site, thrombus position relative to deployed stent-retriever, methods of thrombectomy, and successful advancement of the distal access catheter to the proximal end of the thrombus.

RESULTS

Among 251 patients who underwent mechanical thrombectomy, 154 patients (255 attempts: mTICI 0-2a group, n = 119; mTICI 2b-3 group, n = 136) were included in the analysis. The thrombus position relative to the deployed stent-retriever was likely associated with successful reperfusion, although it was not statistically significant (proximal two-thirds 56.8 %; distal one-third 44.3 %, p = 0.09). Successful advancement of the distal access catheter was related to successful reperfusion both in univariate analysis (success 57.9 %; fail 35.8 %, p < 0.01) and in multivariate regression analysis (odds ratio 2.45; 95 % confidence interval: 1.30-4.61, p < 0.01).

CONCLUSIONS

Successful advancement of the distal access catheter to the proximal end of thrombus might be a key component for successful reperfusion in mechanical thrombectomy.

Selection criteria for anticoagulants: survey of Japanese cardiologists based on their daily clinical practice: the Selection DOAC study

BACKGROUND

In patients with atrial fibrillation (AF), direct oral anticoagulants (DOACs) have been utilized as an alternative to warfarin, which is known to have several limitations. This study aimed to clarify the selection criteria for anticoagulants, considering both individual patient factors and the differences between various drugs.

METHODS

This study conducted a web-based questionnaire from September 20, 2023 to October 3, 2023, among physicians who were members of a cardiology-specific website.

RESULTS

In total, 172 respondents were enrolled in this study. Edoxaban was the most frequently selected anticoagulant (39.1%), followed by apixaban (32.7%) and rivaroxaban (16.8%). Logistic regression analysis revealed that increased concern for adherence enhanced the frequency of selecting edoxaban (odds ratio [OR] = 2.42; p = 0.047), with the opposite trend observed for dabigatran (OR = 0.404; p = 0.029). The selection of apixaban is related to whether the patient is able to maintain a regular lifestyle, including adherence to medication schedules (OR = 1.874; p = 0.031). Furthermore, detailing activities from a medical representative, especially regarding a new indication, were found to influence drug selection for rivaroxaban (OR = 2.422; p = 0.047).

CONCLUSION

This study revealed that edoxaban is the most frequently selected anticoagulant. Although prescribing cardiologists select drugs based on background factors, adherence to medication and information from medical representatives were also crucial factors in the selection process.

Pulmonary Vein Intervention for Severe Pulmonary Vein Stenosis After Atrial Fibrillation Ablation - A Retrospective Cohort Study

BACKGROUND

Pulmonary vein (PV) stenosis (PVS) is a serious complication of atrial fibrillation (AF) ablation. The objective of this study was to describe interventional treatments for PVS after AF ablation and long-term outcomes in Japanese patients.

METHODS AND RESULTS

This multicenter retrospective observational study enrolled 30 patients (26 [87%] male; median age 55 years) with 56 severe PVS lesions from 43 PV interventional procedures. Twenty-seven (90%) patients had symptomatic PVS and 19 (63%) had a history of a single AF ablation. Of the 56 lesions, 41 (73%) were de novo lesions and 15 (27%) were retreated. Thirty-three (59%) lesions were treated with bare metal stents, 14 (25%) were treated with plain balloons, and 9 (16%) were treated with drug-coated balloons. All lesions were successfully treated without any systemic embolic event. Over a median follow-up of 584 days (interquartile range 265-1,165 days), restenosis rates at 1 and 2 years were 35% and 47%, respectively. Multivariate Cox regression analysis revealed devices <7 mm in diameter (hazard ratio [HR] 2.52; 95% confidence interval [CI] 1.04-6.0; P=0.040) and totally occluded lesions (HR 3.33; 95% CI 1.21-9.15; P=0.020) were independent risk factors for restenosis.

CONCLUSIONS

All PVS lesions were successfully enlarged by the PV intervention; however, restenosis developed in approximately half the lesions within 2 years.

Patient concern regarding bleeding side effects from oral anticoagulation therapy for atrial fibrillation: an analysis from the multicentre KiCS-AF registry

AIMS

The purpose of this study is to utilize patient-reported outcomes to determine the percentage of patients concerned about mild to moderate bleeding side effects of anticoagulants.

METHODS AND RESULTS

We consecutively enrolled 3312 newly diagnosed or referred patients for atrial fibrillation (AF) management from 11 sites within the Keio interhospital Cardiovascular Studies-Atrial Fibrillation registry between September 2012 and May 2018. Of these patients, 2636 (79.5%) were taking oral anticoagulants at enrollment. Using the Atrial Fibrillation Effect on Quality-of-life questionnaire (AFEQT), the patients who responded '1: not at all bothered' or '2: hardly bothered' on the seven-point scale regarding bleeding side effects were classified as the 'no OAC concern' group while those responding '3: a little bothered' to '7: extremely bothered' were classified as the 'OAC concern' group. On baseline analysis, 29.3% (n = 772) were 'concerned' about bleeding side effects. The proportion of women and patients with AF-related symptoms was higher in the oral anticoagulant (OAC) concern vs. no OAC concern group (36.9% vs. 29.8%, P < 0.0004 and 66.2% vs. 56.7%, P < 0.0001, respectively). The CHADS2 scores ≥ 2 were comparable between groups. Of the 430 patients in the 1-year follow-up analysis, the proportion of the continued OAC concern group (1 year from enrollment) was 41.6%. The dabigatran, rivaroxaban, and apixaban usage rates were comparable between the two groups in baseline and 1-year follow-up analysis.

CONCLUSION

Approximately one-third of all patients with AF on anticoagulant therapy were concerned regarding bleeding from short- and long-term anticoagulant use.

Trends in prior antithrombotic medication and risk of in-hospital mortality after spontaneous intracerebral hemorrhage: the J-ICH registry

Spontaneous intracerebral hemorrhage (SICH) remains a devastating form of stroke. Prior use of antiplatelets or warfarin before SICH is associated with poor outcomes, but the effects of direct oral anticoagulants (DOACs) remain unclear. This study aimed to clarify trends in prior antithrombotic use and to assess the associations between prior use of antithrombotics and in-hospital mortality using a multicenter prospective registry in Japan. In total, 1085 patients were analyzed. Prior antithrombotic medication included antiplatelets in 14.2%, oral anticoagulants in 8.1%, and both in 1.8%. Prior warfarin use was significantly associated with in-hospital mortality (odds ratio [OR] 5.50, 95% confidence interval [CI] 1.30-23.26, P < 0.05) compared to no prior antithrombotic use. No such association was evident between prior DOAC use and no prior antithrombotic use (OR 1.34, 95% CI 0.44-4.05, P = 0.606). Concomitant use of antiplatelets and warfarin further increased the in-hospital mortality rate (37.5%) compared to warfarin alone (17.2%), but no such association was found for antiplatelets plus DOACs (8.3%) compared to DOACs alone (11.9%). Prior use of warfarin remains an independent risk factor for in-hospital mortality after SICH in the era of DOACs. Further strategies are warranted to reduce SICH among patients receiving oral anticoagulants and to prevent serious outcomes.

Simple risk scoring using sinus rhythm electrocardiograms predicts the incidence of atrial fibrillation in the general population

Atrial fibrillation (AF) is an arrhythmic disease. Prediction of AF development in healthy individuals is important before serious complications occur. We aimed to develop a risk prediction score for future AF using participants' data, including electrocardiogram (ECG) measurements and information such as age and sex. We included 88,907 Japanese participants, aged 30-69 years, who were randomly assigned to derivation and validation cohorts in a ratio of 1:1. We performed multivariate logistic regression analysis and obtained the standardised beta coefficient of relevant factors and assigned scores to them. We created a score based on prognostic factors for AF to predict its occurrence after five years and applied it to validation cohorts to assess its reproducibility. The risk score ranged from 0 to 17, consisting of age, sex, PR prolongation, QT corrected for heart rate prolongation, left ventricular hypertrophy, premature atrial contraction, and left axis deviation. The area under the curve was 0.75 for the derivation cohort and 0.73 for the validation cohort. The incidence of new-onset AF reached over 2% at 10 points of the risk score in both cohorts. Thus, in this study, we showed the possibility of predicting new-onset AF using ECG findings and simple information.

Edge AI Model Deployed for Real-Time Detection of Atrial Fibrillation Risk during Sinus Rhythm

Objectives: The study aimed to develop a deep learning-based edge AI model deployed on electrocardiograph (ECG) devices for the real-time detection of atrial fibrillation (AF) risk during sinus rhythm (SR) using standard 10 s, 12-lead electrocardiograms (ECGs). Methods: A novel approach was used to convert standard 12-lead ECGs into binary images for model input, and a lightweight convolutional neural network (CNN)-based model was trained using data collected by the Japan Agency for Medical and Research Development (AMED) between 2019 and 2022. Patients over 40 years old with digital, SR ECGs were retrospectively enrolled and divided into AF and non-AF groups. The data labeling was supervised by cardiologists. The dataset was randomly allocated into training, validation, and internal testing datasets. External testing was conducted on data collected from other hospitals. Results: The best-trained model achieved an AUC of 0.82 and 0.80, sensitivity of 79.5% and 72.3%, specificity of 77.8% and 77.7%, precision of 78.2% and 76.4%, and overall accuracy of 78.6% and 75.0% in the internal and external testing datasets, respectively. The deployed model and app package utilized 2.5 MB and 40 MB of the available ROM and RAM capacity on the edge ECG device, correspondingly. The processing time for AF risk detection was approximately 2 s. Conclusions: The model maintains comparable performance and improves its suitability for deployment on resource-constrained ECG devices, thereby expanding its potential impact to a wide range of healthcare settings. Its successful deployment enables real-time AF risk detection during SR, allowing for timely intervention to prevent AF-related serious consequences like stroke and premature death.

Characteristics and outcomes in elderly patients with non-valvular atrial fibrillation and high bleeding risk: subanalysis of the J-RHYTHM Registry

Recently, a once-daily dose of edoxaban (15-mg) has been approved for stroke prevention in non-valvular atrial fibrillation (NVAF) patients aged ≥ 80 years, in whom standard oral anticoagulants are not recommended because of high bleeding risk (HBR), based on the ELDERCARE-AF trial. However, information regarding the characteristics and clinical outcomes among such patients is limited. Thus, this study aimed to clarify the characteristics and event rates in elderly patients with NVAF and HBR defined by the ELDERCARE-AF criteria. Of the 7406 NVAF outpatients included in the J-RHYTHM Registry, 60 patients with creatinine clearance (CrCl) < 15 mL/min were excluded. The remaining 7346 patients (age, 69.7 ± 9.9 years; men, 70.9%; warfarin use, 78.7%) were divided into three groups: Group 1, aged < 80 years (n = 6165); Group 2, aged ≥ 80 years without HBR (n = 584); and Group 3, aged ≥ 80 years with HBR (at least one of the followings; CrCl, 15-30 mL/min, history of bleeding, body weight ≤ 45 kg, and antiplatelet use) (n = 597, eligible for 15-mg edoxaban). Patients in Group 3 had a higher prevalence of comorbidities, and therefore, both higher thromboembolic and bleeding risk scores than in the other groups. During the 2-year follow-up period, the incidence rates (per 100 person-years) of thromboembolism in Groups 1, 2, and 3 were 0.7, 1.5, and 2.1 (P < 0.001), major hemorrhage, 0.8, 1.2, and 2.0 (P < 0.001), and all-cause death, 0.8, 2.6, and 4.6 (P < 0.001), respectively. Adjusted hazard ratios of Group 3 were 1.64 (95% confidence interval 0.89-3.04, P = 0.116) for thromboembolism, 1.53 (0.85-2.72, P = 0.154) for major hemorrhage, and 1.84 (1.19-2.85, P = 0.006) for all-cause death compared with Group 1. The NVAF Patients aged ≥ 80 years with HBR defined by the ELDERCARE-AF criteria were certainly at a higher adverse event risk, especially for all-cause death. Clinical trial registration: The J-RHYTHM Registry is registered in the University Hospital Medicine Information Network (UMIN) Clinical Trials Registry (unique identifier: UMIN000001569) http://www.umin.ac.jp/ctr/ .

Catheter ablation in patients with atrial fibrillation and dilated cardiomyopathy

Introduction

Catheter ablation is an effective and safe strategy for treating atrial fibrillation patients. Nevertheless, studies on the long-term outcomes of catheter ablation in patients with dilated cardiomyopathy are limited. This study aimed to assess the electrophysiological characteristics of atrial fibrillation patients with dilated cardiomyopathy and compare the long-term clinical outcomes between patients undergoing catheter ablation and medical therapy.

Method

Patient baseline characteristics and electrophysiological parameters were examined to identify the predictors of atrial fibrillation recurrence following catheter ablation. The clinical outcomes of catheter ablation and medical therapy were compared using the propensity score matched method.

Results

A total of 343 patients were enrolled, with 46 in the catheter ablation group and 297 in the medical therapy group. Among the catheter ablation group, 58.7% (n = 27) had persistent atrial fibrillation. The recurrence rate of atrial arrhythmia was 30.4% (n = 14) after an average follow-up duration of 7.7 years following catheter ablation. The only predictive factor for atrial fibrillation recurrence after catheter ablation was the left atrial diameter. When compared to medical therapy, catheter ablation demonstrated significantly better outcomes in terms of overall survival, freedom from heart failure hospitalization, improvement in left ventricular ejection fraction, and a greater reduction in left ventricular diameter and left atrial diameter after propensity score matching.

Conclusions

Therefore, catheter ablation proves to be effective in providing long-term control of atrial fibrillation in patients with dilated cardiomyopathy. In addition to standard heart failure care, catheter ablation significantly enhanced both morbidity and mortality outcomes and reversed structural remodeling when compared to heart failure medication alone.

External Validation of the HELT-E2S2 Score in Japanese Patients With Nonvalvular Atrial Fibrillation - A Pooled Analysis of the RAFFINE and SAKURA Registries

BACKGROUND

The HELT-E2S2score, which assigns 1 point to Hypertension, Elderly aged 75-84 years, Low body mass index <18.5 kg/m2, and Type of atrial fibrillation (AF: persistent/permanent), and 2 points to Extreme Elderly aged ≥85 years and previous Stroke, has been proposed as a new risk stratification for strokes in Japanese AF patients, but has not yet undergone external validation.

METHODS AND RESULTS

We evaluated the prognostic performance of the HELT-E2S2score for stroke risk stratification using 2 large-scale registries in Japanese AF patients (n=7,020). During 23,241 person-years of follow-up (mean follow-up 1,208±450 days), 287 ischemic stroke events occurred. The C-statistic using the HELT-E2S2score was 0.661 (95% confidence interval [CI], 0.629-0.692), which was numerically higher than with the CHADS2score (0.644, 95% CI 0.613-0.675; P=0.15 vs. HELT-E2S2) or CHA2DS2-VASc score (0.650, 95% CI, 0.619-0.680; P=0.37 vs. HELT-E2S2). In the SAKURA AF Registry, the C-statistic of the HELT-E2S2score was consistently higher than the CHADS2and CHA2DS2-VASc scores across all 3 types of facilities comprising university hospitals, general hospitals, and clinics. However, in the RAFFINE Study, its superiority was only observed in general hospitals.

CONCLUSIONS

The HELT-E2S2score demonstrated potential value for risk stratification, particularly in a super-aged society such as Japan. However, its superiority over the CHADS2or CHA2DS2-VASc scores may vary across different hospital settings.

Effectiveness and safety of edoxaban versus warfarin in patients with nonvalvular atrial fibrillation: a systematic review and meta-analysis of observational studies

Background: Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia type. Patients with AF are often administered anticoagulants to reduce the risk of ischemic stroke due to an irregular heartbeat. We evaluated the efficacy and safety of edoxaban versus warfarin in patients with nonvalvular AF by conducting an updated meta-analysis of real-world studies. Methods: In this comprehensive meta-analysis, we searched two databases, PubMed and EMBASE, and included retrospective cohort observational studies that compared edoxaban with warfarin in patients with nonvalvular AF from 1 January 2009, to 30 September 2023. The effectiveness and safety outcomes were ischemic stroke and major bleeding, respectively. In the final analysis, six retrospective observational studies involving 87,236 patients treated with warfarin and 40,933 patients treated with edoxaban were included. To analyze the data, we used a random-effects model to calculate the hazard ratio (HR). Results: Patients treated with edoxaban had a significantly lower risk of ischemic stroke [hazard ratio (HR) = 0.66; 95% confidence interval (CI) = 0.61-0.70; p < 0.0001] and major bleeding (HR = 0.58; 95% CI = 0.49-0.69; p < 0.0001) than those treated with warfarin. The sensitivity analysis results for ischemic stroke and major bleeding were as follows: HR = 0.66; 95% CI = 0.61-0.70; p < 0.0001 and HR = 0.58; 95% CI = 0.49-0.69; p < 0.0001, respectively. Conclusion: Our findings revealed that edoxaban performed better than warfarin against major bleeding and ischemic stroke.

Mid-Term Feasibility of Percutaneous Left Atrial Appendage Occlusion in Elderly Patients with Non-Valvular Atrial Fibrillation

BACKGROUND

Percutaneous left atrial appendage occlusion (LAAO) therapy using the WATCHMAN system has been introduced to prevent thrombosis and minimize the use of anticoagulants in patients with non-valvular atrial fibrillation. Given the high risk of bleeding and stroke in elderly patients, these patients would be good candidates for this therapy. However, the efficacy and feasibility of LAAO therapy in elderly patients remains uncertain.

METHODS

Consecutive patients who underwent LAAO therapy using the WATCHMAN system in a large academic center between June 2020 and March 2023 were included. The safety and efficacy of LAAO therapy during the 1-year observation period in patients aged ≥85 years old were compared with those in the younger cohort.

RESULTS

A total of 188 patients (78.4 ± 6.9 years old, 133 male patients) were included. 34 patients were ≥85 years old, 96 were between 75 and 84 years old, and 58 were <75 years old. The elderly group had a higher CHA2DS2-VASc score and were at greater risk of falling-related bleeding compared with the younger cohort. The device implantations were successful in all patients except for one. During the 1-year observation period, one patient had a peri-device leak >5 mm and there were 6 device-related cases of thrombosis, whose incidence was not significantly different between the groups (p = 0.98). The cumulative incidences of bleeding and thrombotic events in the elderly group were as low as in the younger cohort (p > 0.05 for both). Most anticoagulants were terminated regardless of age.

CONCLUSION

The mid-term feasibility and efficacy of percutaneous LAAO therapy using the WATCHMAN system in elderly patients aged ≥85 years were as acceptable as in the younger cohort.

Atrial fibrillation in adult congenital heart disease and the general population

BACKGROUND

Atrial fibrillation (AF) in adult patients with congenital heart disease (ACHD) may appear early, depending on individual characteristics.

OBJECTIVES

The goals of this study were to investigate the epidemiological spectrum of AF in the entire cohort of ACHD and compare it with that in the general population.

METHODS

A retrospective study was performed in the nationwide cohort 2000-2014 with AF onset during 2003-2014.

RESULTS

In the cohort of ACHD, 2350 patients had AF; the incidence increased with age, plateauing around age 70. In patients aged 25-29, 45-49, 65-69, 75-79, and ≥80 years, the annual incidence was 1.3, 7.9, 20.6, 23.7, and 21.4/1000 per year, respectively. In the general population without CHD, 347,979 patients had AF; the annual incidence was <1/1000 per year in those aged <55 years but increased steadily with age (3.6, 8.6, and 14.2/1000 per year in aged 65-69, 75-79, and ≥80 years, respectively). Compared with individuals without ACHD, ACHD patients aged <50 years and those aged both 50-54 and 55-59 years exhibited a 20-fold and 10-fold higher incidence of AF, respectively. Patients with complex congenital heart disease and Ebstein's anomaly had the highest risk of AF (cumulative risk >10% by age 50 and >20% by age 60), followed by those with tetralogy of Fallot, tricuspid atresia, endocardial cushion defect, and secundum atrial septal defect (cumulative risk >5% by age 50 and >10% by age 60).

CONCLUSION

Compared with individuals without ACHD, AF in patients with ACHD likely appeared 30 years earlier, with a 10- to 20-fold higher incidence plateauing around age 70. Yet, incidence in individuals without ACHD continued to increase. AF burden in patients with ACHD is not expected to increase in a never-ending way.

Association of high estimated glomerular filtration rate with risk of atrial fibrillation: a nationwide cohort study

Aim

While the relationship between impaired kidney function and atrial fibrillation (AF) is well established, there is limited research exploring the association between elevated estimated glomerular filtration rate (eGFR) and AF development. This study aimed to examine the association between higher-than-normal eGFR and AF risk using a nationwide longitudinal study of the general population in Korea.

Materials and methods

This study utilized the National Health Insurance Service cohort database of Korea, analyzing data from 2,645,042 participants aged 20-79 years who underwent health examinations between 2010 and 2011. Participants with a history of end-stage renal disease, renal transplantation, and AF prior to the index date were excluded. Renal function was assessed using eGFR levels, calculated with the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Baseline characteristics were gathered through questionnaires, while comorbidities and AF occurrence outcomes were identified and validated using diagnostic codes and medication histories. The study employed Kaplan-Meier survival curves and Cox proportional hazard models to evaluate the association between eGFR and AF occurrence.

Results

The mean age of subjects was 48.82 ± 10.08 years. Over a median follow-up of 9.58 years, 27,469 (1.04%) AF cases were identified. The risk for AF increased in the higher-than-normal decile, as demonstrated by Kaplan-Meier survival curves (p < 0.001). The eGFR <30 mL/min/1.73 m2 group was associated with an increased risk of AF [hazard ratio (HR): 1.22, 95% confidence interval (CI) (1.01, 1.46), p = 0.039], while the eGFR >120 mL/min/1.73 m2 group was associated with a decreased risk of AF [HR: 0.88, 95% CI (0.78, 0.98), p = 0.045]. Compared to the 5th decile, the 1st [HR: 1.08, 95% CI (1.03, 1.13), p = 0.010] eGFR decile was significantly associated with an increased risk of AF, while the 10th [HR: 0.77, 95% CI (0.70, 0.85), p < 0.001] eGFR decile was significantly associated with a reduced risk of AF.

Conclusion

The study revealed that individuals with eGFR>120 mL/min/1.73 m2 or those falling within eGFR 10th decile (>113.41 mL/min/1.73 m2) demonstrated an inverse association linked to a reduced risk of AF. Our study suggests that general population with higher-than-normal eGFR levels may have a lower risk of developing AF.

Regular pulse checks for patients with non-cardioembolic stroke in rehabilitation hospitals to improve recognition and detection of atrial fibrillation (the ESCORT study): protocol for a prospective multicenter observational study

Background

Cryptogenic stroke (CS) are heterogeneous in origin; however, most CS are embolic mechanism. Paroxysmal atrial fibrillation (AF) is suspected to be a major type of CS that leads to severe cerebral infarction without anticoagulant use. Therefore, the identification of AF is vital in patients with CS. However, patients are often unaware of AF because they have no symptoms, and AF may not be detected on an electrocardiogram (ECG) or Holter ECG on admission. After patients with stroke are treated in the acute phase, they are promptly transferred to a rehabilitation hospital for functional recovery. Once the patient is transferred to a hospital, a few attempts are made to detect AF. In addition, rehabilitation therapists are considered to have insufficient awareness of the possibility of undiagnosed AF.

Objective

This study aimed to increase the understanding of the importance of AF detection in patients with ischemic stroke among therapists in rehabilitation hospitals and to investigate whether regular pulse screening can aid in the detection of AF. If AF was detected, we determined the rate and timing of AF detection and identified the patient characteristics.

Methods

This multicenter prospective observational study aimed to detect AF in patients with non-cardiac stroke at rehabilitation hospitals. Therapists performed pulse checks before, during, and after rehabilitation. If arrhythmia or tachycardia was detected, an ECG was performed, and the physician checked for AF. If the patient complained of chest symptoms, electrocardiography (ECG) was performed to check for AF. We investigated the characteristics, laboratory data, cognitive status, complications, such as stroke recurrence, and functional outcomes of patients with AF.

Results

The study is in the enrollment phase. Recruitment began in September 2022 and will end in August 2023. Patients have provided written informed consent. The main results have been submitted for publication in your journal.

Conclusion

The findings of this study will help identify patients with AF in rehabilitation hospitals and improve awareness among therapists.

Risk factor profile for newly diagnosed atrial fibrillation: 4-year follow-up of annual health examinations in a Japanese Adult Cohort

Background

Detecting unknown atrial fibrillation (AF) would provide an opportunity to prevent ischemic stroke by instituting appropriate anticoagulation. Although opportunistic screening of older patients is recommended in current guidelines, which patients may benefit from intensive AF screening remains unclear. We sought to clarify the risk factor profile for newly diagnosed AF in annual health examinations of a Japanese adult cohort.

Methods

Among 141 441 Japanese patients who underwent annual health examinations in 2014, 87 872 patients aged ≥20 years without known AF who had undergone electrocardiography were analyzed (mean age: 47 ± 12 years; 64% men). The absence of known AF was confirmed by prior electrocardiography in 2012 and/or 2013. Newly diagnosed AF was observed in 244 patients in 2014-2017 (mean age: 62 ± 12 years; 83% men).

Results

In the multivariable analysis, waist circumference obesity (hazard ratio [HR], 1.5; 95% confidence interval [CI], 1.13-1.99; p = .005) high blood pressure (HR, 1.9; 95% CI, 1.01-3.59; p = .047), on-treatment hypertension (HR, 1.53; 95% CI, 1.01-2.31; p = .046), and daily alcohol drinking (HR, 2.18; 95% CI, 1.52-3.12; p < .001) were significantly associated with newly diagnosed AF.

Conclusions

In this Japanese cohort, waist circumference obesity, hypertension, and alcohol drinking were independent predictors of newly diagnosed AF in annual medical examinations. This finding encourages further evaluation of systematic AF screening programs in at-risk populations.

Prevalence and Treatment of Arrhythmias in Patients With Transthyretin and Light-Chain Cardiac Amyloidosis

Background: Various types of arrhythmia are observed in patients with cardiac amyloidosis, but the prevalence of arrhythmia has not been fully investigated. This study investigated the prevalence and treatment of arrhythmias in patients with cardiac amyloidosis before the introduction of new agents for amyloidosis, such as tafamidis. Methods and Results: Of 53 patients who were histologically diagnosed with cardiac amyloidosis at 10 centers in western Japan between 2009 and 2021, 43 who were diagnosed on the basis of immunohistochemical staining were evaluated in this study. Of these 43 patients, 13 had immunoglobulin light-chain (AL) amyloidosis and 30 had transthyretin (ATTR) amyloidosis; further, 27 had atrial tachyarrhythmia, 13 had ventricular tachyarrhythmia, and 17 had bradyarrhythmia. Atrial fibrillation (AF) was the most common arrhythmia in patients with cardiac amyloidosis (n=24; 55.8%), especially among those with ATTR amyloidosis (70.0% of ATTR vs. 23.1% of AL). Eleven (25.6%) patients were treated with a cardiac implantable device. All 3 patients with pacemakers were alive at the last follow-up (median 76.7 months; interquartile range [IQR] 4.8-146.4 months). Of the 8 patients who underwent AF ablation, there was no recurrence in 6 (75%) after a median of 39.3 months (IQR 19.8-59.3 months). Conclusions: The prevalence of various arrhythmias was high in patients with cardiac amyloidosis. AF occurred most frequently in patients with cardiac amyloidosis, especially among patients with ATTR.

Association between periodontal disease status and risk of atrial fibrillation: a nationwide population-based cohort study

BACKGROUND

Periodontal disease can activate an immune process linked to systemic diseases, including atrial fibrillation. However, the relationship between periodontal disease and atrial fibrillation remains unclear.

AIM

This study aimed to investigate whether changes in periodontal disease status are associated with the risk of atrial fibrillation.

METHODS

Using the National Health Insurance Database Korea, participants who underwent the first oral health examination in 2003 and a second examination in 2005-2006 without a history of atrial fibrillation were included. Participants were grouped according to changes in periodontal disease status during two oral examinations: periodontal disease-free, periodontal disease-recovered, periodontal disease-developed, and periodontal disease-chronic. The outcome was the incidence of atrial fibrillation.

RESULTS

The study included 1,254,515 participants, with a median follow-up of 14.3 years and 25,402 (2.02%) cases of atrial fibrillation occurred. During follow-up, the risk of atrial fibrillation was highest in the periodontal disease-chronic group, followed by the periodontal disease-developed, periodontal disease-recovered, and periodontal disease-free groups (p for trend < 0.001). Moreover, recovery from periodontal disease was associated with a reduced risk of atrial fibrillation compared to a chronic periodontal disease status (Hazard ratio: 0.97, 95% Confidence interval: 0.94-0.99, p = 0.045). The development of periodontal disease was associated with an increased risk of atrial fibrillation compared to being periodontal disease-free (Hazard ratio: 1.04, 95% Confidence interval: 1.01-1.08, p = 0.035).

CONCLUSION

Our findings suggest that changes in periodontal disease status impact the risk of atrial fibrillation. Management of periodontal disease may help prevent atrial fibrillation.

Rationale and design of the NEO-NORMAL-AF study examination of the usefulness of implantable loop recorder for arrhythmia detection including atrial fibrillation in heart failure with non-reduced ejection fraction cases: a pilot study

INTRODUCTION

The incidence of arrhythmia in heart failure with non-reduced ejection fraction (HFnon-rEF) in patients who have a history of hospitalisation is unclear. The aim of this study is to investigate the usefulness of an implantable loop recorder (ILR) for arrhythmia detection including atrial fibrillation (AF) in HFnon-rEF patients after discharge.

METHODS AND ANALYSIS

This is a multicentre single arm study to evaluate the usefulness of ILR for detecting arrhythmia. The eligible patients are HFnon-rEF patients (left ventricular ejection fraction ≥40%) aged ≥20 years with a history of hospitalisation. The ILR will be implanted for qualified patients, and ECGs will be monitored and recorded for 1 year to check for arrhythmias. The primary endpoint is new-onset 6 min or more persistent AF detected by ILR. Secondary endpoints are 30 s or more persistent supraventricular tachycardia and ventricular tachycardia, 3 s or more persistent pause, bradycardia with 40 beats per minutes or lower heart rate, AF burden, all-cause death, cardiovascular death, hospital readmission due to exacerbation of HF, acute coronary syndrome, ischaemic or haemorrhagic stroke, non-pharmacological therapy such as pacemaker implantation and ablation.

CONCLUSIONS

This study is expected to provide valuable findings regarding arrhythmia in HFnon-rEF patients, and elucidate a potential new therapeutic approach for HFnon-rEF.

TRIAL REGISTRATION NUMBER

This trial has been registered in the Japan Registry of Clinical Trials (jRCT) (Trial Registration: jRCTs052210060).

Long-term outcome and risk factors associated with events in patients with atrial fibrillation treated with oral anticoagulants: The ASSAF-K registry

BACKGROUND

Oral anticoagulant therapy for atrial fibrillation (AF) has changed dramatically. Direct oral anticoagulant (DOAC) therapy is administered by general practitioners and specialists. However, the beneficial long-term effects and safety of DOACs have not been well investigated in real-world clinical practice.

METHODS

The ASSAF-K (a study of the safety and efficacy of OAC therapy in the treatment of AF in Kanagawa), a prospective, multi-center, observational study, was conducted to clarify patient characteristics, status of OAC treatment, long-term outcomes, and adverse events, including cerebrovascular disease, bleeding, and death.

RESULTS

A total of 4014 patients were enrolled (hospital: 2500 cases; clinic: 1514 cases). The number of patients in the final dataset was 3367 (mean age, 72.6 ± 10.0 years; males, 66.3 %). CHA₂DS₂-VASc and HAS-BLED scores were 3.0 ± 1.6 and 2.2 ± 1.0, respectively. The risk factors of the primary composite outcome (all-cause death, serious bleeding events, cerebral hemorrhage, and stroke) were higher age, lower body mass index, lower diastolic blood pressure, lower creatine clearance, history of heart failure, history of stroke, and medication of anti-platelet agents. The event-free rates of the primary composite outcome with DOACs, warfarin, and without OACs were 92.7 %, 88.0 %, and 87.4 %, respectively. The event rate of DOACs was significantly lower than that of warfarin [HR 0.63 (95 % CI 0.48-0.81)], and similar results were observed after adjustment for AF stroke risk score [HR 0.70 (95 % CI 0.54-0.90)]. Serious bleeding events tended to occur less frequently with DOACs compared with warfarin [unadjusted HR 0.53 (95 % CI 0.31-0.91), adjusted HR 0.61 (95 % CI 0.33-1.11)].

CONCLUSIONS

This multi-center registry demonstrated the long-term outcome in patients with AF treated with and without OACs and suggests that DOAC therapy is safe and beneficial in hospitals and clinics.

Cost-effectiveness analysis of cardiac implantable electronic devices with reactive atrial-based antitachycardia pacing

AIMS

Reactive atrial-based anti-tachycardia pacing (rATP) in pacemakers (PMs) and cardiac resynchronization therapy defibrillators (CRT-Ds) has been reported to prevent progression of atrial fibrillation, and this reduced progression is expected to decrease the risk of complications such as stroke and heart failure (HF). This study aimed to assess the cost-effectiveness of rATP in PMs and CRT-Ds in the Japanese public health insurance system.

METHODS AND RESULTS

We developed a Markov model comprising five states: bradycardia, post-stroke, mild HF, severe HF, and death. For devices with rATP and control devices without rATP, we compared the incremental cost-effectiveness ratio (ICER) from the payer's perspective. Costs were estimated from healthcare resource utilisation data in a Japanese claims database. We evaluated model uncertainty by analysing two scenarios for each device. The ICER was 763 729 JPY/QALY (5616 EUR/QALY) for PMs and 1,393 280 JPY/QALY (10 245 EUR/QALY) for CRT-Ds. In all scenarios, ICERs were below 5 million JPY/QALY (36 765 EUR/QALY), supporting robustness of the results.

CONCLUSION

According to a willingness to pay threshold of 5 million JPY/QALY, the devices with rATP were cost-effective compared with control devices without rATP, showing that the higher reimbursement price of the functional categories with rATP is justified from a healthcare economic perspective.

Prognostic Predictors of Tricuspid Regurgitation Worsening after Mitral Regurgitation Surgery with Mild Tricuspid Regurgitation

We aimed to investigate the prevalence and predictors of postoperative tricuspid regurgitation (TR) worsening in patients with mitral regurgitation (MR) and concomitant ≤mild TR. A total of 620 patients underwent surgery for MR from 2013 to 2017. Of these, 260 had ≤mild preoperative TR and no concomitant tricuspid valve surgery and were enrolled in this single-center retrospective study. The primary endpoint was postoperative worsening of ≥moderate TR. The primary endpoint occurred in 28 of 260 patients (11%) during the follow-up period [median: 4.1 years (interquartile range: 2.9-6.1 years)]. In the multivariable analysis, age, female sex, and left atrial volume index (LAVI) were significant predictors of the primary outcome during intermediate-term follow-up (age: hazard ratio [HR] 1.05 per 1-year increment, 95% confidence interval [CI] 1.02-1.10, P = 0.003; female sex: HR 3.53, 95% CI 1.61-7.72, P = 0.002; LAVI: HR 1.17 per 10-mL/m2 increment, 95% CI 1.07-1.26, P < 0.001). The optimal LAVI cut-off value for predicting postoperative TR worsening was 79 mL/m2 (area under the curve: 0.69). A high LAVI (>79 mL/m²) was significantly associated with a low rate of freedom from postoperative TR worsening compared with a low LAVI (≤79 mL/m²) (82.6% vs 93.9% at 5 years, respectively; log-rank P = 0.008). In patients with ≤mild preoperative TR and no concomitant tricuspid surgery, the rate of postoperative TR worsening was 11% during intermediate-term follow-up. LA enlargement in patients with MR and ≤mild preoperative TR was significantly associated with postoperative TR worsening.

Registry for Evaluating Healthy Life Expectancy and Long-Term Outcomes after Catheter Ablation of Atrial Fibrillation in the Very Elderly (REHEALTH AF) study: rationale and design of a prospective, multicentre, observational, comparative study

INTRODUCTION

Data are lacking on the extent to which patients with non-valvular atrial fibrillation (AF) who are aged ≥80 years benefit from ablation treatment. The question pertains especially to patients' postablation quality of life (QoL) and long-term clinical outcomes.

METHODS AND ANALYSIS

We are initiating a prospective, registry-based, multicentre observational study that will include patients aged ≥80 years with non-valvular AF who choose to undergo treatment by catheter ablation and, for comparison, such patients who do not choose to undergo ablation (either according to their physician's advice or their own preference). Study subjects are to be enrolled from 52 participant hospitals and three clinics located throughout Japan from 1 June 2022 to 31 December 2023, and each will be followed up for 1 year. The planned sample size is 660, comprising 220 ablation group patients and 440 non-ablation group patients. The primary endpoint will be the composite incidence of stroke/transient ischaemic attack (TIA) or systemic embolism (SE), another cardiovascular event, major bleeding and/or death from any cause. Other clinical events such as postablation AF recurrence, a fall or bone fracture will be recorded. We will collect standard clinical background information plus each patient's Clinical Frailty Scale score, AF-related symptoms, QoL (Five-Level Version of EQ-5D) scores, Mini-Mental State Examination (optional) score and laboratory test results, including measures of nutritional status, on entry into the study and 1 year later, and serial changes in symptoms and QoL will also be secondary endpoints. Propensity score matching will be performed to account for covariates that could affect study results.

ETHICS AND DISSEMINATION

The study conforms to the Declaration of Helsinki and the Ethical Guidelines for Clinical Studies issued by the Ministry of Health, Labour and Welfare, Japan. Results of the study will be published in one or more peer-reviewed journals.

TRIAL REGISTRATION NUMBER

UMIN000047023.

The roles of HIF-1α signaling in cardiovascular diseases

Oxygen is essential for living organisms. Molecular oxygen binds to hemoglobin and is delivered to every organ in the body. In several cardiovascular diseases or anemia, local oxygen tension drops below its physiological level and tissue hypoxia develops. In such conditions, the expression of hypoxia-responsive genes increases to alleviate the respective condition. The hypoxia-responsive genes include the genes coding erythropoietin (EPO), vascular endothelial growth factor-A, and glycolytic enzymes. Hypoxia-inducible factor (HIF)-1α, HIF-2α, and HIF-3α are transcription factors that regulate the hypoxia-responsive genes. The HIF-α proteins are continuously degraded by an oxygen-dependent degrading pathway involving HIF-prolyl hydroxylases (HIF-PHs) and von Hippel-Lindau tumor suppressor protein. However, upon hypoxia, this degradation ceases and the HIF-α proteins form heterodimers with HIF-1β (a constitutive subunit of HIF), which results in the induction of hypoxia responsive genes. HIF-1α and HIF-2α are potential therapeutic targets for renal anemia, where EPO production is impaired due to chronic kidney diseases. Small molecule HIF-PH inhibitors are currently used to activate HIF-α signaling and to increase plasma hemoglobin levels by restoring EPO production. In this review, we will discuss the current understanding of the roles of the HIF-α signaling pathway in cardiovascular diseases. This will include the roles of HIF-1α in cardiomyocytes as well as in stromal cells including macrophages.

Estimation of mechanical properties by transcatheter monitoring using local impedance and contact force

The mechanical properties of the myocardium in the left ventricle and right atrium were estimated by simultaneously measuring the local impedance (LI) and contact force (CF) using an ablation catheter. Radiofrequency catheter ablation (RFCA) is a well-established arrhythmia treatment. Monitoring the RF power, CF and properties of myocardium during RFCA are necessary to estimate the effect of ablation. Indices, such as CF, lesion size index and ablation index, do not include the myocardium mechanical properties. Therefore, there is the risk of side effects, such as cardiac tamponade, by excessive catheter indentation into vulnerable areas. We propose the simultaneous measurement of LI and CF for estimating the myocardial mechanical properties to reduce the side effects. In this study, an in vitro experimental system was constructed to measure LI and CF via the catheter. The relationship between the porcine myocardial tissue thickness and CF-LI curve was investigated using the left ventricle and right atrium. Power function coefficients approximating the CF-LI curve increased with thicker left ventricle. The thickness of the myocardium can be estimated by simultaneously measuring LI and CF. Intraoperative measurement of the myocardial mechanical properties can be used to determine the ablation conditions at each site.

Impact of cognitive impairment on clinical outcomes in elderly patients with atrial fibrillation: ANAFIE Registry

Background

This subcohort study of All Nippon AF In the Elderly (ANAFIE) Registry based on 33 275 elderly patients (aged ≥75 years) with non-valvular atrial fibrillation (NVAF) investigated the relationship between cognitive function and 2-year clinical outcomes.

Methods

A total of 2963 (mean age, 81.4 years) patients participated in this subcohort study and were classified as having normal cognition (Mini-Mental State Examination (MMSE) score ≥24/30) or cognitive impairment (score ≤23/30) at baseline. Patients with a decrease of >2 points after 24 months were classified as having cognitive decline.

Results

At baseline, 586 (19.8%) patients had cognitive impairment. These patients tended to be older and had poorer general conditions than patients with normal cognition. The 2-year probability of stroke/systemic embolic events (SEEs), major bleeding and intracranial haemorrhage was numerically higher; those of cardiovascular death, all-cause death and net clinical outcome (composite of stroke/SEE, major bleeding and all-cause death) were significantly higher (all p<0.001) in patients with cognitive impairment versus normal cognition. In multivariate analysis, the risks of cardiovascular death (p=0.021), all-cause death (p<0.001) and net clinical outcome (p<0.001) were higher in patients with cognitive impairment versus those with normal cognition. After 24 months, 642 of 1915 (33.5%) patients with repeated MMSE determination had cognitive decline. Educational background <9 years, older age and concomitant cerebrovascular disorders were significant risk factors of cognitive decline at the 2-year follow-up.

Conclusions

Elderly patients with NVAF with cognitive impairment have a higher mortality risk than those with normal cognition. Several significant risk factors of cognitive decline were identified at 2-year follow-up.

Trial registration number

UMIN000024006 (http://www.umin.ac.jp/).

The Relationship between Holter Electrocardiography and Atrial Fibrillation Diagnosis Using Real-World Data in Japan

The relationship between Holter electrocardiography (ECG) and atrial fibrillation (AF) diagnosis in the real world has not been widely evaluated in Japan.This is a claims-based retrospective study using a health insurance claims database provided by DeSC Healthcare Corporation. We identified patients with at least one Holter for any purpose during the data period from April 2015 to November 2020 and without diagnosis of AF before the tests (n = 19,739). We obtained a whole picture of Holter and AF diagnosis after correcting for population distribution bias in the dataset. Based on this picture and the assumption that the patient had AF at the 1^st Holter whose AF was detected for the first time at the second or subsequent Holter, we estimated the number of diagnosis with AF and overlooked AF by initial Holter. We conducted sensitivity analyses changing the definition of AF, the potential detection period, and the washout period (a period required to avoid including patients who have already been diagnosed with AF or who have already undergone several Holters) to confirm the validity of the base scenario.Among patients for analysis, 88.4% had only one Holter. The percentage of AF diagnosis by initial Holter was 7.6%. The percentage of AF overlooked by initial Holter was estimated to be 31.4% and this value did not change much by sensitivity analyses.It was estimated that approximately 30% of AF patients were overlooked by initial Holter, and reducing the overlooked rate will be a clinical challenge.

Cost-effectiveness of left atrial appendage closure with Watchman for non-valvular atrial fibrillation patients in Japan

AIMS

Left atrial appendage closure (LAAC) has been demonstrated to be cost-saving relative to oral anticoagulants for stroke prophylaxis in patients with non-valvular atrial fibrillation (NVAF) in the United States and Europe. This study assessed the cost-effectiveness of LAAC with the Watchman device relative to warfarin and direct oral anticoagulants (DOACs) for stroke risk reduction in NVAF from a Japanese public healthcare payer perspective.

METHODS

A Markov model was developed with 70-year-old patients using a lifetime time horizon. LAAC clinical inputs were from pooled, 5-year PROTECT AF and PREVAIL trials; warfarin and DOAC inputs were from published meta-analyses. Baseline stroke and bleeding risks were from the SALUTE trial on LAAC. Cost inputs were from the Japanese Medical Data Vision database. Probabilistic and one-way sensitivity analyses were performed.

RESULTS

Over the lifetime time horizon, LAAC was less costly than warfarin (savings of JPY 1,878,335, equivalent to US $17,600) and DOACs (savings of JPY 1,198,096, equivalent to US $11,226). LAAC also provided 1.500 more incremental quality-adjusted life years (QALYs) than warfarin and 0.996 more than DOACs. In probabilistic sensitivity analysis, LAAC was cost-effective relative to warfarin and DOACs in 99.98% and 99.73% of simulations, respectively. LAAC dominated (had higher cumulative QALYs and was less costly than) warfarin and DOACs in 89.94% and 83.35% of simulations, respectively.

CONCLUSIONS

Over a lifetime time horizon, LAAC is cost-saving relative to warfarin and DOACs for stroke risk reduction in NVAF patients in Japan and is associated with improved quality-of-life.

Age-related reference intervals for ambulatory electrocardiographic parameters in healthy individuals

Background

The advent of novel monitoring technologies has dramatically increased the use of ambulatory electrocardiography (AECG) devices. However, few studies have conducted detailed large-scale investigations on the incidence of arrhythmias over 24 h, especially ectopy, in healthy individuals over a wide age range.

Objectives

This study aimed to investigate the incidence of arrhythmias detected using AECG and associated factors, in healthy individuals, over a wide age range.

Methods

In this cross-sectional study, we performed AECG on 365 healthy volunteers (median [interquartile range]: 48 [36, 67], 20-89 years, 165 men) under free-running conditions for 24 h. Ultrasonic echocardiography and heart rate variability analysis were performed to explore the factors associated with the incidence of arrhythmias.

Results

The 97.5th percentile of single ventricular ectopy (VE) was 149/day, 254/day, and 1,682/day in the 20-39-, 40-59- and 60-89-year age groups, respectively; that of single supraventricular ectopy (SVE) was 131/day, 232/day, and 1,063/day, respectively. Multivariate analysis revealed that aging was the only independent significant factor influencing the frequency of VE (β = 0.207, P = 0.001). Age (β = 0.642, P < 0.001), body mass index (BMI) (β = -0.112, P = 0.009), and the root mean square of successive differences in RR intervals (β = 0.097, P = 0.035) were factors significantly associated with SVE frequency.

Conclusions

Age-specific reference intervals of VE and SVE in a large population of healthy participants over a wide age range were generated. VE and SVE increased with age; SVE was influenced by BMI and the aging-induced decrease in parasympathetic tone activity.

Initial report of percutaneous left atrial appendage closure in hemodialysis patients with atrial fibrillation and high risk of bleeding in Japan

In the countries like Japan where anticoagulation is not recommended in hemodialysis patients, the feasibility of percutaneous left atrial appendage closure (LAAC) in hemodialysis patients with non-valvular atrial fibrillation (NVAF) accompanying high risks of thromboembolic stroke and bleeding remains unknown. Peri-procedural and 45-day clinical outcomes following LAAC using WATCHMAN system, which were performed in our institute between Jun 2020 and April 2022 according to the Japanese Circulation Society guidelines, were retrospectively compared between those with and without hemodialysis. 118 patients (median 79 years, 81 men) consisting of 25 hemodialysis patients and 93 non-hemodialysis patients were included. CHADS score was 3 (2, 4) in the hemodialysis patients and 3 (2, 4) in the non-hemodialysis patients (p = 0.98). HAS-BREAD score was 4 (3, 5) in the hemodialysis patients and 3 (2, 3) in the non-hemodialysis patients (p < 0.001). All procedures were successful, except for a non-hemodialysis patient with a larger left atrial appendage. There were no major complications during index hospitalization and 45-day observational period, except for a hemodialysis patient with suspected bleeding and a non-hemodialysis patient who died due to cardiac amyloidosis. LAAC seems to be feasible in hemodialysis patients with high risks of thromboembolic events and bleedings.

Mechanism and management of atrial fibrillation in the patients with obstructive sleep apnea

Obstructive sleep apnea (OSA) is a highly prevalent disorder in patients with atrial fibrillation (AF). Although there has been an increase in the incidence of AF due to the aging population, it has been reported that OSA is still underdiagnosed because many patients remain asymptomatic or unaware of the symptoms associated with OSA, such as daytime sleepiness. Untreated OSA reduces the effectiveness of AF treatment, regardless of pharmacological or non-pharmacological modes of therapy, such as catheter ablation. Experimental and clinical studies have shown that OSA pathophysiology is multifactorial, comprising of hypoxemia, hypercapnia, autonomic dysfunction, negative intrathoracic pressure changes, and arousals of OSA, and lead to AF. Both the acute and long-term effects of obstructive apnea episodes are involved in the development of an arrhythmogenic substrate of AF. Undiagnosed OSA causes underutilized opportunities for more effective AF management. Therefore, it is important to screen for OSA in all patients being considered for rhythm control therapy. However, regardless of the growing evidence of the negative prognostic impact of OSA, there is a lack of awareness regarding this connection not only among patients but also among cardiologists and arrhythmia specialists. There is a barrier to performing a systemic screening for OSA in clinical practice. Therefore, it is important to establish a comprehensive OSA care team for the efficient diagnosis and treatment of OSA. This review provides the current understanding of OSA and its relationship to AF and the importance of the diagnosis and management of OSA in AF.

Incidence of stroke, systemic embolism and bleeding events in patients without anticoagulation based on real-world data in Japan: a retrospective cohort study

OBJECTIVES

To examine the incidence of stroke or systemic embolic events (SSEs) and bleeding events in untreated patients with non-valvular atrial fibrillation (NVAF) after widespread use of direct oral anticoagulant agents (DOACs).

DESIGN

Multicentre, non-interventional, observational, retrospective cohort study using real-world data in Japan (2016-2018).

SETTING

The Mie, Musashino University study of NVAF, which used the Mie-Life Innovation Promotion Center Database. This is a regional clinical database involving one university hospital and eight general hospitals in Mie Prefecture in Japan.

PARTICIPANTS

Japanese patients with NVAF (n=7001).

PRIMARY AND SECONDARY OUTCOME

The incidence of SSEs and bleeding events.

RESULTS

A total of 7001 patients with NAVF were registered, and 53.0% were treated with DOACs, 10.6% were treated with warfarin and 36.4% had no treatment. Additionally, 29.5% of patients with a CHADS2 (congestive heart failure, hypertension, age≥75 years, diabetes, previous stroke or transient ischemic attack) score of 3-6 were untreated. In the no treatment group, the SSE rates by the CHADS2 score (0, 1, 2 and 3-6) were 1.4%, 1.4%, 3.2% and 8.0%, respectively. The rates of bleeding events by the CHADS2 score (0, 1, 2 and 3-6) in the no treatment group were 0.7%, 1.0%, 1.2% and 2.9%, respectively. A multivariate analysis of SSEs in components of the CHADS2 showed that the adjusted HRs were 2.32 for heart failure, 1.66 for an age ≥75 years, 1.81 for diabetes mellitus and 5.84 for prior stroke or transient ischaemic attack.

CONCLUSIONS

Approximately one-third of the patients do not receive any anticoagulation in the modern DOAC era in Japan. The SSE rate increases by the CHADS2 score. The SSE rate is low in patients with a CHADS2 score &lt;1, supporting no indication of anticoagulation in current guidelines. In patients with a CHADS2 score &gt;1, the use of anticoagulant drug therapy is recommended because of a higher risk of stroke.

Left atrial appendage closure for stroke prevention in nonvalvular atrial fibrillation: A current overview

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice and its prevalence increases with age. AF causes palpitations, heart failure, and cardiogenic embolism. Of them, the most critical and fatal complication is a cardio-embolic event. Oral anticoagulation plays a central role in reducing stroke risk in AF patients. Recently, when oral anticoagulation is considered in patients with non-valvular AF who are eligible for direct oral coagulations, they are preferred to vitamin K antagonist based on accumulating evidence. Although many patients can tolerate oral anticoagulation, there is a subset of patients who cannot tolerate long-term oral anticoagulation. Such a subset has a higher bleeding risk as indicated by the HAS-BLED score under oral anticoagulation. This subset of patients requires effective and safe non-pharmacological alternative therapies for stroke prevention. One of the promising non-pharmacological therapies is left atrial appendage closure. Three randomized controlled trials demonstrated non-inferiority of percutaneous left atrial appendage closure using WATCHMAN family to oral anticoagulation (Boston Scientific, Marlborough, MA, USA). WATCHMAN FLX, which was innovated following WATCHMAN 2.5, was associated with fewer safety events and a higher success rate of effective appendage closure. Nevertheless, several unsolved issues remain, including device-related thrombosis, post-treatment antithrombotic therapy, and peri-device leakage. Left atrial appendage closure for patients with non-valvular AF may be an alternative therapy to avoid cardiac embolism for high bleeding risk patients with contraindications to long-term oral anticoagulation therapy.

Comparison of Direct Oral Anticoagulants and Warfarin in Patients With Atrial Fibrillation and an Aortic Bioprosthetic Valve

BACKGROUND

Current guidelines equally recommend direct oral anticoagulants (DOACs) and warfarin for atrial fibrillation (AF) patients with a bioprosthetic valve (BPV); however, there are limited data comparing DOACs and warfarin in AF patients with an aortic BPV.

METHODS AND RESULTS

This post-hoc subgroup analysis of a multicenter, prospective, observational registry (BPV-AF Registry) aimed to compare DOACs and warfarin in AF patients with an aortic BPV. The primary outcome was a composite of stroke, systemic embolism, major bleeding, heart failure requiring hospitalization, all-cause death, or BPV reoperation. The analysis included 479 patients (warfarin group, n=258; DOAC group, n=221). Surgical aortic valve replacement was performed in 74.4% and 36.7% of patients in the warfarin and DOAC groups, respectively. During a mean follow up of 15.5 months, the primary outcome occurred in 45 (17.4%) and 32 (14.5%) patients in the warfarin and DOAC groups, respectively. No significant difference was found in the primary outcome between the 2 groups (adjusted hazard ratio: 0.88, 95% confidence interval: 0.51-1.50). No significant multiplicative interaction was observed between the anticoagulant effects and type of aortic valve procedure (P=0.577).

CONCLUSIONS

Among AF patients with an aortic BPV, no significant difference was observed in the composite outcome of adverse clinical events between patients treated with warfarin and those treated with DOACs, suggesting that DOACs can be used as alternatives to warfarin in these patients.

Accuracy of wristwatch-type photoplethysmography in detecting atrial fibrillation in daily life. EUROPEAN HEART JOURNAL. DIGITAL HEALTH 2022;3:455-464. [PMID: 36712156 PMCID: PMC9707983 DOI: 10.1093/ehjdh/ztac041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Aims

Detection of asymptomatic paroxysmal atrial fibrillation is challenging. Smartphone- or smartwatch-based photoplethysmography is efficient at detecting irregular rhythms using pulse waves but is too complex for older patients. We aimed to evaluate the detection accuracy of atrial fibrillation by a wristwatch-type continuous pulse wave monitor (PWM) in daily life.

Methods and results

Patients at high risk of atrial fibrillation but with no history of atrial fibrillation (n = 163; mean CHADS₂ score, 1.9) and patients with known atrial fibrillation (n = 123, including 34 with persistent atrial fibrillation) underwent PWM and telemetry electrocardiogram recording for 3 days. Risk of atrial fibrillation was judged using the 'Kyorin Atrial Fibrillation Risk Score', a scoring system based on previously reported atrial fibrillation risk scoring systems. The PWM assessed the presence of atrial fibrillation at 30 min intervals, and the results were compared with the telemetry electrocardiogram findings. The PWMs accurately diagnosed two patients with paroxysmal atrial fibrillation in the high-risk group. The PWMs accurately diagnosed 48 of the 55 patients with atrial fibrillation in the known-atrial fibrillation group. The PWM accuracy in detecting patients with atrial fibrillation was as follows: sensitivity, 98.0%; specificity, 90.6%; positive predictive value, 69.4%; negative predictive value, 99.5%. The respective values for intervals with atrial fibrillation were 86.9%, 98.8%, 89.6%, and 98.5%.

Conclusion

The wristwatch-type PWM has shown feasibility in detecting atrial fibrillation in daily life and showed the possibility of being used as a screening tool.