Burden of stroke and other cardiovascular complications in patients with atrial fibrillation hospitalized in France

Comprehensive analysis of lactylation-related gene and immune microenvironment in atrial fibrillation

Background

Atrial fibrillation (AF) is a common arrhythmia associated with an increased risk of stroke, heart failure, and mortality. Immune infiltration plays a crucial role in AF pathogenesis, yet its mechanisms remain unclear. Lactylation, a novel post-translational modification, has been implicated in immune regulation, but its association with AF remains unexplored. This study aims to elucidate the relationship between lactylation and immune infiltration in AF and identify potential diagnostic biomarkers.

Methods

Gene expression data from left atrial tissue samples of AF and sinus rhythm (SR) patients were obtained from the Gene Expression Omnibus (GEO) database (GSE41177, GSE79768, GSE115574, GSE2240, GSE14975, and GSE128188). Differentially expressed genes (DEGs) between AF and SR samples were identified, followed by pathway enrichment and immune infiltration analysis. Correlation analysis and WGCNA were performed to assess interactions between lactylation-related genes and immune-associated DEGs. Machine learning models, including Random Forest and Support Vector Machine (SVM), were applied to select potential AF-related diagnostic biomarkers, and validated in the animal model (beagles; n = 6).

Results

A total of 5,648 DEGs were identified, including six lactylation-related genes (DDX39A, ARID3A, TKT, NUP50, G6PD, and VCAN). Co-expression and WGCNA analyses identified lactylation- and immune-associated gene modules in AF. Functional enrichment analysis highlighted immune-related pathways such as T cell activation and neutrophil degranulation. A five-gene diagnostic model (FOXK1, JAM3, LOC100288798, MCM4, and RCAN1) achieved high predictive accuracy (AUC = 0.969 in training, 0.907 in self-test, and 0.950, 0.760, 0.890 in independent datasets). Experimental validation confirmed the upregulated expression of these biomarkers in AF.

Conclusion

This study reveals a strong association between lactylation-related genes and immune infiltration in AF, suggesting their involvement in immune remodeling. The identified five-gene signature serves as a potential diagnostic biomarker set, offering novel insights into AF pathogenesis and contributing to improved diagnosis and targeted therapeutic strategies. Future studies integrating proteomic and single-cell analyses will further clarify the role of lactylation in AF.

Evolution in electrophysiology 100 years after Einthoven: translational and computational innovations in rhythm control of atrial fibrillation

In 1924, the Dutch physiologist Willem Einthoven received the Nobel Prize in Physiology or Medicine for his discovery of the mechanism of the electrocardiogram (ECG). Anno 2024, the ECG is commonly used as a diagnostic tool in cardiology. In the paper 'Le Télécardiogramme', Einthoven described the first recording of the now most common cardiac arrhythmia: atrial fibrillation (AF). The treatment of AF includes rhythm control, aiming to alleviate symptoms and improve quality of life. Recent studies found that early rhythm control might additionally improve clinical outcomes. However, current therapeutic options have suboptimal efficacy and safety, highlighting a need for better rhythm-control strategies. In this review, we address the challenges related to antiarrhythmic drugs (AADs) and catheter ablation for rhythm control of AF, including significant recurrence rates and adverse side effects such as pro-arrhythmia. Furthermore, we discuss potential solutions to these challenges including novel tools, such as atrial-specific AADs and digital-twin-guided AF ablation. In particular, digital twins are a promising method to integrate a wide range of clinical data to address the heterogeneity in AF mechanisms. This may enable a more mechanism-based tailored approach that may overcome the limitations of previous precision medicine approaches based on individual biomarkers. However, several translational challenges need to be addressed before digital twins can be routinely applied in clinical practice, which we discuss at the end of this narrative review. Ultimately, the significant advances in the detection, understanding, and treatment of AF since its first ECG documentation are expected to help reduce the burden of this troublesome condition.

Cost-effectiveness of left atrial appendage occlusion during cardiac surgery in France: An economic evaluation based on the LAAOS III study

OBJECTIVES

Left atrial appendage occlusion during cardiac surgery is a therapeutic option for stroke prevention in patients with atrial fibrillation. The effectiveness and safety of left atrial appendage occlusion have been evaluated in several studies, including the LAAOS-III trial. While these studies have demonstrated efficacy and safety, the long-term economic impact of this surgical technique has not yet been assessed. Here, we aimed to evaluate the cost-effectiveness and cost-utility of left atrial appendage occlusion during cardiac surgery over a long-term time horizon.

METHODS

Our study was based on a model representing an hypothetical cohort with the same characteristics as LAAOS-III trial patients. We modelled the incidence of ischemic strokes and systemic embolisms in each intervention arm: "occlusion" and "no-occlusion," using a one-month cycle length with a 20-year time horizon. Regarding occlusion devices, sutures, staples, or an approved surgical occlusion device (AtriClip™-AtriCure, Ohio, USA) could be used.

RESULTS

Our model generated an average cost savings of 607 euros per patient and an incremental gain of 0.062 quality-adjusted life years (QALYs), resulting an incremental cost-utility ratio (ICUR) of €-9,775/QALY. The scenario analysis in which occlusion was systematically performed using the AtriClip™ device generated an ICUR of €3,952/QALY gained.

CONCLUSIONS

In the base-case analysis, the strategy proved to be more effective and less costly, confirming left atrial appendage occlusion during cardiac surgery as an economically dominant strategy. The scenario analysis also appeared cost-effective, although it did not result in cost savings. This study provides a new perspective on the assessment of the cost-effectiveness of these techniques.

Identification of Plasmatic MicroRNA-206 as New Predictor of Early Recurrence of Atrial Fibrillation After Catheter Ablation Using Next-generation Sequencing

BACKGROUND

Catheter ablation (CA) of atrial fibrillation (AF) is indicated in patients with recurrent and symptomatic AF episodes. Despite the strict inclusion/exclusion criteria, AF recurrence after CA remains high. Identification of a novel biomarker that would predict AF recurrence would help to stratify the patients. The aim of the study was to seek novel biomarkers among the plasmatic microRNAs (miRNAs, miRs).

METHODS

A prospective monocentric study was conducted. A total of 49 consecutive AF patients indicated for CA were included. Blood sampling was performed prior to CA. RNA was isolated from plasma using commercial kits. In the exploration phase, small RNA sequencing was performed in ten AF patients (five with and five without AF recurrence) using Illumina instrument. In the validation phase, levels of selected miRNAs were determined using quantitative reverse transcription polymerase chain reaction (qRT-PCR) in all participants.

RESULTS

Altogether, 22 miRNAs were identified as altered between the groups by next-generation sequencing (using the DESeq2 algorithm). Using qRT-PCR, levels of the five most altered miRNAs (miR-190b/206/326/505-5p/1296-5p) were verified in the whole cohort. Plasma levels of hsa-miR-206 were significantly higher in patients with early (within 6 months) AF recurrence and showed an increase of risk recurrence,2.65 times by every increase in its level by 1 unit in the binary logistic regression.

CONCLUSION

We have identified a set of 22 plasmatic miRNAs that differ between the patients with and without AF recurrence after CA and confirmed hsa-miR-206 as a novel miRNA associated with early AF recurrence. Results shall be verified in a larger independent cohort.

The Association between Diagnosis-to-Ablation Time and the Recurrence of Atrial Fibrillation: A Retrospective Cohort Study

BACKGROUND

Catheter ablation (CA) for atrial fibrillation (AF) is superior to antiarrhythmic drugs in maintaining sinus rhythm. Novel evidence suggests that increasing the time between the first diagnosis of AF and ablation, or diagnosis-to-ablation time (DAT), is a predictor for AF recurrence post-ablation.

PURPOSE

Our primary objective was to investigate the relationship between DAT and AF recurrence after a first ablation.

METHODS

Patients with AF who underwent CA in our center were enrolled consecutively, and a retrospective analysis was performed. DAT was treated as a continuous variable and reported as a median for the group with recurrence and the group without recurrence. DAT was also considered as a categorical variable and patients were stratified into three categories: DAT < 1 year, DAT < 2 years, and DAT < 4 years.

RESULTS

The cohort included 107 patients, with a mean age of 54.3 ± 11.7 years. Mean DAT was significantly longer in those with AF recurrence: 4.9(3.06) years versus 3.99(3.5) (p = 0.04). The Kaplan-Meier curve revealed a higher likelihood of AF-free status over time for patients with DAT < 2 years compared to those with DAT > 2 years (p = 0.04). Cox multivariate analysis indicated that left atrial volume index (LAVI), obstructive sleep apnoea (OSA), and DAT > 2 years were independently associated with AF recurrence after a single AF ablation procedure (p = 0.007, p = 0.02, and p = 0.03, respectively).

CONCLUSION

A shorter duration between the first AF diagnosis and AF ablation is associated with an increased likelihood of procedural success after a single AF ablation procedure.

Clinical and economic impact of first-line or drug-naïve catheter ablation and delayed second-line catheter ablation for atrial fibrillation using a patient-level simulation model

AIMS

To determine the clinical and economic implications of first-line or drug-naïve catheter ablation compared to antiarrhythmic drugs (AADs), or shorter AADs-to-Ablation time (AAT) in atrial fibrillation (AF) patients in France and Italy, using a patient level-simulation model.

MATERIALS AND METHODS

A patient-level simulation model was used to simulate clinical pathways for AF patients using published data and expert opinion. The probabilities of adverse events (AEs) were dependent on treatment and/or disease status. Analysis 1 compared scenarios of treating 0%, 25%, 50%, 75% or 100% of patients with first-line ablation and the remainder with AADs. In Analysis 2, scenarios compared the impact of delaying transition to second-line ablation by 1 or 2 years.

RESULTS

Over 10 years, increasing first-line ablation from 0% to 100% (versus AAD treatment) decreased stroke by 12%, HF hospitalization by 29%, and cardioversions by 45% in both countries. As the rate of first-line ablation increased from 0% to 100%, the overall 10-year per-patient costs increased from €13,034 to €14,450 in Italy and from €11,944 to €16,942 in France. For both countries, the scenario with no delay in second-line ablation had fewer AEs compared to the scenarios where ablation was delayed after AAD failure. Increasing rates of first-line or drug-naïve catheter ablation, and shorter AAT, resulted in higher cumulative controlled patient years on rhythm control therapy.

LIMITATIONS

The model includes assumptions based on the best available clinical data, which may differ from real-world results, however, sensitivity analyses were included to combat parameter ambiguity. Additionally, the model represents a payer perspective and does not include societal costs, providing a conservative approach.

CONCLUSION

Increased first-line or drug-naïve catheter ablation, and shorter AAT, could increase the proportion of patients with controlled AF and reduce AEs, offsetting the small investment required in total AF costs over 10 years in Italy and France.

Estimating the cost impact of atrial fibrillation using a prospective cohort study and population-based controls

AIMS

Atrial fibrillation (AF) costs are expected to be substantial, but cost comparisons with the general population are scarce. Using data from the prospective Swiss-AF cohort study and population-based controls, we estimated the impact of AF on direct healthcare costs from the Swiss statutory health insurance perspective.

METHODS

Swiss-AF patients, enrolled from 2014 to 2017, had documented, prevalent AF. We analysed 5 years of follow-up, where clinical data, and health insurance claims in 42% of the patients were collected on a yearly basis. Controls from a health insurance claims database were matched for demographics and region. The cost impact of AF was estimated using five different methods: (1) ordinary least square regression (OLS), (2) OLS-based two-part modelling, (3) generalised linear model-based two-part modelling, (4) 1:1 nearest neighbour propensity score matching and (5) a cost adjudication algorithm using Swiss-AF data non-comparatively and considering clinical data. Cost of illness at the Swiss national level was modelled using obtained cost estimates, prevalence from the Global Burden of Disease Project, and Swiss population data.

RESULTS

The 1024 Swiss-AF patients with available claims data were compared with 16 556 controls without known AF. AF patients accrued CHF5600 (EUR5091) of AF-related direct healthcare costs per year, in addition to non-AF-related healthcare costs of CHF11100 (EUR10 091) per year accrued by AF patients and controls. All five methods yielded comparable results. AF-related costs at the national level were estimated to amount to 1% of Swiss healthcare expenditure.

CONCLUSIONS

We robustly found direct medical costs of AF patients were 50% higher than those of population-based controls. Such information on the incremental cost burden of AF may support healthcare capacity planning.

Multi-event survival analysis through dynamic multi-modal learning for ICU mortality prediction

BACKGROUND AND OBJECTIVE

Survival analysis is widely applied for assessing the expected duration of patient status towards event occurrences such as mortality in healthcare domain, which is generally considered as a time-to-event problem. Patients with multiple complications have high mortality risks and oftentimes require specific intensive care and clinical treatments. The progression of complications is time-varying according to disease development and intrinsic interactions between complications with respect to mortality are uncertain. Classical methods for mortality prediction and survival analysis in critical care, such as risk scoring systems and cause-specific survival models, were not designed for this multi-event survival analysis problem and able to measure the competing risks of death for mutually exclusive events. In addition, multivariate temporal information of complications is not taken into consideration while estimating differentiated mortality risks in the early stage.

METHODS

In this paper, we propose a novel multi-event survival analysis solution using a tree-based autoregressive survival model of multi-modal electronic health record data. Specifically, we focus on modeling the temporal trajectory of complications and estimating the mortality risk associated with multiple potential complications simultaneously. In dynamic modeling, no assumptions are made for the relationships between time-dependent variables and risk transition over time.

RESULTS

Validated with the eICU database, our model achieves a better prediction performance with C-index ranging in 74-80%, compared to state-of-the-art machine learning methods in the literature, for the complications of acute respiratory distress syndrome and cardiovascular disease cases.

CONCLUSIONS

Our model provides the distinguishable mortality risk curves over time for specific complications and the track of risk development that could potentially support the ICU resource reallocation.

[Organization and costs of stroke care in outpatient settings: Systematic review]

OBJECTIVE

To review the bibliography on stroke costs (ICD-10 code I63) in the field of primary care.

DESIGN

Systematic review.

DATA SOURCES

PubMed/Medline, ClinicalTrials.gov, Cochrane Reviews, EconLit, and Ovid/Embase between 01/01/2012-12/31/2021 with descriptors included in Medical Subject Heading (MeSH).

SELECTION OF STUDIES

Those with a description of the costs of activities carried out in the out-of-hospital setting. Systematic reviews were included; prospective and retrospective observational studies; analysis of databases and total or partial costs of stroke as a disease (COI). Articles were added using the snowball method. The studies were excluded because: a) not specifically related to stroke; b) in editorial or commentary format; c) irrelevant after review of the title and abstract; and d) gray literature and non-academic studies were excluded.

DATA EXTRACTION

They were assigned a level of evidence according to the GRADE levels. Direct and indirect cost data were collected.

RESULTS AND CONCLUSIONS

Thirty studies, of which 14 (46.6%) were related to post-stroke costs and 12 (40%) to cardiovascular prevention costs. The results show that most of them are retrospective analyzes of different databases of short-term hospital care, and do not allow a detailed analysis of the costs by different segments of services. The possibilities for improvement are centered on primary and secondary prevention, selection and pre-hospital transfer, early discharge with support, and social and health care.

Signal Quality Analysis for Long-Term ECG Monitoring Using a Health Patch in Cardiac Patients

Cardiovascular diseases (CVD) represent a serious health problem worldwide, of which atrial fibrillation (AF) is one of the most common conditions. Early and timely diagnosis of CVD is essential for successful treatment. When implemented in the healthcare system this can ease the existing socio-economic burden on health institutions and government. Therefore, developing technologies and tools to diagnose CVD in a timely way and detect AF is an important research topic. ECG monitoring patches allowing ambulatory patient monitoring over several days represent a novel technology, while we witness a significant proliferation of ECG monitoring patches on the market and in the research labs, their performance over a long period of time is not fully characterized. This paper analyzes the signal quality of ECG signals obtained using a single-lead ECG patch featuring self-adhesive dry electrode technology collected from six cardiac patients for 5 days. In particular, we provide insights into signal quality degradation over time, while changes in the average ECG quality per day were present, these changes were not statistically significant. It was observed that the quality was higher during the nights, confirming the link with motion artifacts. These results can improve CVD diagnosis and AF detection in real-world scenarios.

Cryoablation as a first-line therapy for atrial fibrillation: current status and future prospects

INTRODUCTION

Atrial fibrillation (AF) is a common chronic and progressive heart rhythm disorder. For those in whom sinus rhythm is desired, contemporary clinical practice guidelines recommend antiarrhythmic drugs (AADs) as the initial therapy. However, these medications have modest efficacy and are associated with significant adverse effects.

AREAS COVERED

The current article reviews the evidence surrounding first line catheter ablation, particularly the emerging evidence surrounding the use of cryoballoon ablation as a first-line therapy. The focus of the review is on the outcomes of arrhythmia freedom, quality of life, healthcare utilisation and safety. In addition, the article will review novel cryoablation systems.

EXPERT OPINION

: Recent evidence suggests that cryoballoon ablation significantly improves arrhythmia outcomes (e.g., freedom from any atrial tachyarrhythmia or symptomatic atrial tachyarrhythmia, reduction in arrhythmia burden), patient-reported outcomes (e.g., symptoms and quality of life), and healthcare resource utilization (e.g., hospitalization), without increasing the risk of adverse events. These findings are relevant to patients, providers, and healthcare systems, as it helps inform the decision-making regarding the initial choice of rhythm-control therapy in patients with treatment-naïve AF.

Apixaban versus other anticoagulants in patients with nonvalvular fibrillation: a comparison of all-cause and event-related costs in real-life setting in France

OBJECTIVES

Compare costs associated with all-cause healthcare resource use (HCRU), stroke/systemic thromboembolism (STE) and major bleedings (MB) between patients with non-valvular atrial fibrillation (NVAF) initiating apixaban or other oral anticoagulants (OACs).

METHODS

We performed a retrospective cohort study using the French healthcare claims database, including NVAF patients between 2014/01/01 and 2016/12/31, followed until 2016/12/31. We used 4 sub-cohorts of OAC-naive patients, respectively initiating apixaban, dabigatran, rivaroxaban or VKAs. We matched patients initiating apixaban with patients initiating each other OACs using 1:n propensity score matching. All-cause HCRU and event-related costs by OAC treatment were estimated and compared between matched patients using generalised-linear models with gamma-distribution and two-part models.

RESULTS

There were 175,766 patients in the apixaban-VKA, 181,809 in the apixaban-rivaroxaban, and 42,490 in the apixaban-dabigatran matched cohorts. Patients initiating apixaban had significantly lower HCRU costs than patients initiating VKA (€1,105 vs. €1,578, p < 0.0001), dabigatran (€993 vs. €1,140, p < 0.0001) and rivaroxaban (€1,013 vs. €1,088 p < 0.0001). They have had significantly lower costs related to stroke/STE and MB than patients initiating VKA (respectively, €183 vs. €449 and €147 vs. €413; p < 0.0001), rivaroxaban (respectively, €145 vs. €197 and €129 vs. €193; p < 0.0001), and lower costs related to stroke/STE than patients initiating dabigatran (€135 vs. €192, p < 0.02). Costs related to MB were not significantly different in patients initiating apixaban and those initiating dabigatran (€119 vs. €149, p = 0.07).

CONCLUSIONS

HCRU and most event-related costs were lower in patients initiating apixaban compared to other OACs. Apixaban may be cost-saving compared to VKAs, and significantly cheaper than other DOACs, although cost differences are limited.

New evidence: Cryoballoon ablation vs. antiarrhythmic drugs for first-line therapy of atrial fibrillation

Atrial fibrillation (AF) is a commonly encountered chronic and progressive heart rhythm disorder, characterized by exacerbations and remissions. Contemporary clinical practice guidelines recommend a trial of antiarrhythmic drugs (AADs) as the initial therapy for sinus rhythm maintenance; however, these medications have modest efficacy and are associated with significant adverse effects. Recently, several trials have demonstrated that an initial treatment strategy of cryoballoon catheter ablation significantly improves arrhythmia outcomes (e.g. freedom atrial tachyarrhythmia and reduction in arrhythmia burden), produces clinically meaningful improvements in patient-reported outcomes (e.g. symptoms and quality of life), and significantly reduces subsequent healthcare resource utilization (e.g. hospitalization), without increasing the risk of serious or any adverse events. These findings are relevant to patients, providers, and healthcare systems, helping inform the decision regarding the initial choice of rhythm-control therapy in patients with treatment-naïve AF.

Cryoballoon Ablation as Initial Treatment for Atrial Fibrillation: JACC State-of-the-Art Review

Atrial fibrillation (AF), the most common sustained arrhythmia observed in clinical practice, is a chronic and progressive disorder characterized by exacerbations and remissions. Guidelines recommend antiarrhythmic drugs as the initial therapy for the maintenance of sinus rhythm; however, antiarrhythmic drugs have modest efficacy to maintain sinus rhythm and can be associated with significant adverse effects. An initial treatment strategy of cryoballoon catheter ablation in patients with treatment-naïve AF has been shown to significantly improve arrhythmia outcomes (freedom from any, or symptomatic atrial tachyarrhythmia), produce clinically meaningful improvements in patient-reported outcomes (symptoms and quality of life), and significantly reduce subsequent health care resource use (hospitalization), and it does not increase the risk of serious or any adverse events compared with initial antiarrhythmic drug therapy. These findings are relevant to inform patients, providers, and health care systems regarding the initial choice of rhythm-control therapy in patients with treatment-naïve AF.

Use of real-world evidence in meta-analyses and cost-effectiveness models

Real-world evidence (RWE) provides external validity, supplementing and enhancing the randomized controlled trial data with valuable information on patient behaviors and outcomes, turning efficacy and safety results into real-world effectiveness and risks, but the use of RWE is associated with challenges. The objectives of this communication were to (1) summarize all guidance on how to conduct an RWE meta-analysis (MA) and how to develop an RWE cost-effectiveness model, (2) to describe our experience, challenges faced and solutions identified, (3) to provide recommendations on how to conduct such analyses. No formal guidelines on how to conduct an RWE MA or to develop an RWE cost-effectiveness model were identified. Using the context of non-vitamin K antagonist oral anticoagulants in stroke prevention in atrial fibrillation, we conducted an RWE MA, after having identified sources of uncertainty. We then implemented the results in an RWE cost-effectiveness model, defined as a model where all inputs come from RWE, including all parameters related to treatment effect. Based on challenges faced, our first recommendation relates to the necessity of conducting sensitivity analyses, either based on clinical or methodological considerations. Our second recommendation is the need for extensive collaboration with a wide range of experts, during the development of the analyses protocols, the implementation of the analyses and the interpretation of the results. RWE may address a number of gaps related to the treatment effect, and RWE economic evaluations for the treatment effect can provide extremely valuable insights into real-world economic value of interventions. As the increased recognition of the value of RWE could influence health technology assessment decision, and current practices, this communication supports the urgent need of more formal guidelines.

Diagnostic accuracy of smart gadgets/wearable devices in detecting atrial fibrillation: A systematic review and meta-analysis

BACKGROUND

Recently, smart devices have been used for medical purposes, particularly to screen for atrial fibrillation. However, current data on the diagnostic performance of these devices are scarce.

AIMS

We performed a systemic review and meta-analysis to assess the accuracy of atrial fibrillation diagnosis by smart gadgets/wearable devices.

METHODS

We comprehensively searched the MEDLINE, EMBASE and Cochrane databases for all works since the inception of each database until January 2020. Included in this review were published observational studies of the diagnostic accuracy of smartphones or smartwatches in detecting atrial fibrillation. We calculated the area under the summary receiver operating characteristic curves and pooled sensitivities and specificities.

RESULTS

Participants in our study were from the general population or were patients with underlying atrial fibrillation. In the overall analyses, the areas under the summary receiver operating characteristic curves were 0.96 and 0.94 for smartphones and smartwatches, respectively. Smartphones had a sensitivity of 94% and a specificity of 96%, and smartwatches showed similar diagnostic accuracy, with a specificity of 94% and a sensitivity of 93%. In subgroup analyses, we found no difference in diagnostic accuracy between photoplethysmography and single-lead electrocardiography.

CONCLUSIONS

This study suggests that smart devices have similar diagnostic accuracies. Regarding atrial fibrillation detection methods, there was also no difference between photoplethysmography and single-lead electrocardiography. However, further studies are warranted to determine their clinical implications in atrial fibrillation management.

Real-world cost-effectiveness of rivaroxaban and apixaban vs VKA in stroke prevention in non-valvular atrial fibrillation in the UK

BACKGROUND

Morbidity and mortality associated with non-valvular atrial fibrillation (NVAF) imposes a substantial economic burden on the UK healthcare system.

OBJECTIVES

An existing Markov model was adapted to assess the real-world cost-effectiveness of rivaroxaban and apixaban, each compared with a vitamin K antagonist (VKA), for stroke prevention in patients with NVAF from the National Health Service (NHS) and personal and social services (PSS) perspective.

METHODS

The model considered a cycle length of 3 months over a lifetime horizon. All inputs were drawn from real-world evidence (RWE): baseline patient characteristics, clinical event and persistence rates, treatment effect (meta-analysis of RWE studies), utility values and resource use. Deterministic and probabilistic sensitivity analyses were performed.

RESULTS

The incremental cost per quality-adjusted life year was £14,437 for rivaroxaban, and £20,101 for apixaban, compared with VKA. The probabilities to be cost-effective compared with VKA were 90% and 81%, respectively for rivaroxaban and apixaban, considering a £20,000 threshold. In both comparisons, the results were most sensitive to clinical event rates.

CONCLUSIONS

These results suggest that rivaroxaban and apixaban are cost-effective vs VKA, based on RWE, considering a £20,000 threshold, from the NHS and PSS perspective in the UK for stroke prevention in patients with NVAF. This economic evaluation may provide valuable information for decision-makers, in a context where RWE is more accessible and its value more acknowledged.

Role of intermediate-conductance calcium-activated potassium channels in atrial fibrillation in canines with rapid atrial pacing

PURPOSE

The aim of the present study was to explore the role of intermediate-conductance Ca²⁺-activated K⁺ (SK4) in atrial fibrillation (AF) inducibility in canines with rapid atrial pacing.

METHODS

Eighteen dogs were divided into the control group, the pacing group and the stellate ganglion ablation (SGA) + pacing group. In the pacing group, dogs were subjected to rapid atrial pacing, and the atrial effective refractory period (AERP) and AF inducibility were measured. After cessation of 7-h pacing, SK4 inhibitor (TRAM-34) was administered. After SGA, the SGA + pacing group received the same procedure of pacing and electrophysiological measurement as the pacing group. The expression of SK4 was measured in the left atrium (LA) and the right atrium (RA) in the three groups.

RESULTS

The duration of the AERP decreased, while the number of AF episodes, the duration of induced AF, and the amplitude of stellate ganglion neural activity all increased after rapid atrial pacing. TRAM-34 completely inhibited AF induction in the pacing group. There was no significant difference in AERP shortening or AF vulnerability between the SGA + pacing group and the control group. The expression of SK4 in the LA and RA was higher in the pacing group than in the control and SGA + pacing groups. However, there was no significant difference in the expression of SK4 in the LA or the RA between the SGA + pacing group and the control group.

CONCLUSION

The higher expression of SK4 plays an important role in AF induction and the increased expression of SK4 in the atrium is related to SG activity during rapid atrial pacing.

Real-world cost-effectiveness of rivaroxaban compared with vitamin K antagonists in the context of stroke prevention in atrial fibrillation in France

Objective

The objective was to assess the real-world cost-effectiveness of rivaroxaban, versus vitamin K antagonists (VKAs), for stroke prevention in patients with atrial fibrillation (AF) from a French national health insurance perspective.

Methods

A Markov model was developed with a lifetime horizon and cycle length of 3 months. All inputs were drawn from real-world evidence (RWE) studies: data on baseline patient characteristics at model entry were obtained from a French RWE study, clinical event rates as well as persistence rates for the VKA treatment arm were estimated from a variety of RWE studies, and a meta-analysis provided comparative effectiveness for rivaroxaban compared to VKA. Model outcomes included costs (drug costs, clinical event costs, and VKA monitoring costs), quality-adjusted life-years (QALY) and life-years (LY) gained, incremental cost per QALY, and incremental cost per LY. Sensitivity analyses were performed to test the robustness of the model and to better understand the results drivers.

Results

In the base-case analysis, the incremental total cost was €714 and the total incremental QALYs and LYs were 0.12 and 0.16, respectively. The resulting incremental cost/QALY and incremental cost/LY were €6,006 and €4,586, respectively. The results were more sensitive to the inclusion of treatment-specific utility decrements and clinical event rates.

Conclusions

Although there is no official willingness-to-pay threshold in France, these results suggest that rivaroxaban is likely to be cost-effective compared to VKA in French patients with AF from a national insurance perspective.

Annual rate of newly treated atrial fibrillation by age and gender in France, 2010-2016

Few studies are available on atrial fibrillation (AF) burden at a whole country scale. The objective was to estimate the rate of AF patients newly treated with oral anticoagulants (OAC) in France each year between 2010 and 2016 and to describe age and gender differences. We used the French national health data system. For each year between 2010 and 2016, we identified patients aged over 20 initiating OAC. OAC indicated for the treatment of AF was determined by hospitalization diagnoses, specific procedures and registered long-term disease status, or a multiple imputation process for patients with no recorded information as to why they initiated OAC. Among the 421,453 individuals initiating OAC treatment in 2016, the estimated number of newly treated AF patients was 210,131, women accounting for 46%, patients under 65 years old 17%, and 21.4% of patients living in most deprived area. Age-standardized rates reached 400/100,000 inhabitants. Approximately 19% of patients were recently hospitalized for heart failure and 7% for stroke. Age-standardized rates increased by 35% over the study period in both genders, with a marked increase in patients under 55 (+ 41%) and those over 85 years old (+ 60%). Annual rates of AF patients newly treated with OAC increased by 35% between 2010 and 2016. Important differences in rates were observed according to age, gender and the deprivation level of the living area.

A Systematic Review of Direct Cardiovascular Event Costs: An International Perspective

INTRODUCTION

There is a lack of comprehensive cost information for cardiovascular events since 2013.

OBJECTIVE

A systematic review on the contemporary cost of cardiovascular events was therefore undertaken.

METHODS

Methods complied with those recommended by the Cochrane Collaboration and the Centre for Reviews and Dissemination. Studies were unrestricted by language, were from 2013 to 23 December 2017, and included cost-of-illness data in adults with the following cardiovascular conditions: myocardial infarction (MI), stroke, transient ischaemic attack (TIA), heart failure (HF), unstable angina (UA), coronary artery bypass graft (CABG), percutaneous coronary intervention (PCI), or peripheral artery disease (PAD). Seven electronic databases were searched, namely Embase (Ovid), MEDLINE (Ovid), MEDLINE In-Process Citations and Daily Update (Ovid), NHS Economic Evaluation Database (NHS EED), Health Technology Assessment (HTA) database, Cochrane Central Register of Controlled Trials (CENTRAL), and PubMed. The included studies reported data from a variety of years (sometimes prior to 2013), so costs were inflated and converted to $US, year 2018 values, for standardization.

RESULTS

After de-duplication, 29,945 titles and abstracts and then 403 full papers were screened; 82 studies (88 papers) were extracted. Year 1 average cost ranges were as follows: MI ($11,970 in Sweden to $61,864 in the USA), stroke ($10,162 in Spain to $46,162 in the USA), TIA ($6049 in Sweden to $25,306 in the USA), HF ($4456 in China to $49,427 in the USA), UA ($11,237 in Sweden to $31,860 in the USA), PCI ($17,923 in Italy to $45,533 in the USA), CABG ($17,972 in the UK to $76,279 in the USA). One Swedish study reported PAD costs in a format convertible to $US, 2018 values, with a mean annual cost of $15,565.

CONCLUSIONS

There was considerable unexplained variation in contemporary costs for all major cardiovascular events. One emerging theme was that average costs in the USA were considerably higher than anywhere else.

ABC (Atrial fibrillation Better Care) Pathway and Healthcare Costs in Atrial Fibrillation: The ATHERO-AF Study

BACKGROUND

The Atrial fibrillation Better Care (ABC) pathway has been proposed to streamline patient management in an integrated, holistic manner. Compliance to ABC resulted in lower incidence of cardiovascular events, but its impact on health-related costs has not been evaluated.

METHODS

Exploratory analysis of costs related to cardiovascular events in the ATHERO-AF prospective cohort study including atrial fibrillation patients on vitamin K antagonists. A Diagnosis-Related Group code provided by the Italian Ministry of Health was assigned to each event to estimate the relative cost. The analysis was performed by dividing patients according to ABC pathway components.

RESULTS

Overall, 118 cardiovascular events incurred a cost of 1,017,354 euros (1,149,610 USD). The mean total costs were 13,050 (14,747 USD) and 11,218 euros (12,676 USD) for a non-fatal cardiac event or ischaemic stroke, respectively. The cost-saving was 719 euros (813 USD) per patient-year for patients in group A vs non-A, 703 euros (794 USD) for B vs non-B, 480 euros (542 USD) for C vs non-C and 2776 euros (3,137 USD) for ABC vs non-ABC. The cost per event increased with the number of uncontrolled ABC components: 507 euros (573 USD) for 1, 965 euros (1,091 USD) for 2 and 3,431 euros (3,877 USD) for patients not having any of the three components of the ABC.

CONCLUSIONS

Management of atrial fibrillation patients according to the ABC pathway was associated with significantly lower health-related costs. Application of the ABC pathway may help reduce healthcare costs related to cardiovascular events in this high-risk patient population.

Trimethylamine N-oxide as a risk marker for ischemic stroke in patients with atrial fibrillation

Trimethylamine N-oxide (TMAO) is an independent risk factor of cardiovascular disease. Our objective was to explore the relation between TMAO and ischemic stroke (IS) in patients with atrial fibrillation (AF). A total of 68 patients with AF with IS and 111 ones without IS were enrolled. The plasma levels of TMAO remarkably increased in IS-AF patients (8.25 ± 1.58 µM) compared with patients with AF (2.22 ± 0.09 µM, P < 0.01). The receiver operating characteristic analysis revealed that the best cutoff value of TMAO to predict IS in patients with AF was 3.53 µM with 75.0% sensitivity and 92.8% specificity (area under the curve: 0.917, 95% confidence intervals: 0.877-0.957). Univariate and multivariate logistic regression analysis showed that TMAO was an independent predictor in IS. The level of TMAO was correlated with the CHA2DS2-VASc score. In conclusion, TMAO was an independent predictor of IS, which could potentially refine stroke stratification in patients with AF.

Change in lipid profile and risk of new-onset atrial fibrillation in patients with chronic heart failure: A 3-year follow-up observational study in a large Chinese hospital

In chronic heart failure (CHF), new-onset atrial fibrillation (AF) is associated with increased morbidity and mortality. We aimed to evaluate the influence of dyslipidemia on the incidence of new-onset AF in patients with CHF.In this single-center observational study, 308 patients with CHF and no history of AF were followed-up for 3 years. Of the 291 patients who attended the 1-year follow-up, 78 had developed AF (AF group; 10 deaths), while 213 had not (sinus rhythm [SR] group). Changes in lipid profile (ΔTC for total cholesterol and ΔLDLc for low-density lipoprotein cholesterol) were analyzed.The groups differed significantly regarding the decrease in lipid levels from baseline to the 1-year follow-up (AF vs SR: for ΔLDLc, 23.35 vs 7.80 mg/dL, P = .02; for ΔTC, 23.95 vs -2.76 mg/dL, P = .001). At the 3-year follow-up, new-onset AF was noted in 21 of the 188 living patients in the SR group. Cox proportional hazards analysis revealed ΔLDLc and ΔTC as independent risk factors for new-onset AF (hazard ratio, 1.018 and 1.013, respectively, per standard deviation increment), with higher incidence of new-onset AF for ΔTC > 9.65 mg/dL (P = .02) and for ΔLDLc > 9.73 mg/dL (P = .005).In CHF, pronounced decrease in LDLc and TC is associated with new-onset AF.

Predictors for total hospital and cardiology cost claims among patients with atrial fibrillation initiating dabigatran or acenocoumarol in The Netherlands

AIMS

The prevalence of atrial fibrillation (AF) has increased over the past years due to aging of the population, and healthcare costs associated with AF reflect a significant financial burden. The aim of this study was to explore predictors for the real-world AF-related in-hospital costs in patients that recently initiated anticoagulation with acenocoumarol or dabigatran.

METHODS

Predictors for claimed total hospital care costs and cardiology costs in AF patients were explored by using hospital financial claims data from propensity score matched patient groups in a large Dutch community hospital. This study analyzed the total dataset (n = 766) and carried out a secondary analysis for all matched pairs of anticoagulation naïve AF patients (n = 590) by ordinal regression.

RESULTS

Dabigatran was a predictor for significantly lower cardiology and total hospital care costs (Odds Ratio [OR] = 0.43, 95% confidence interval (CI) = 0.33-0.57; and OR = 0.60, 95% CI = 0.46-0.79, respectively). Female gender was a predictor for lower total hospital care costs. Predictors for an increase in total hospital care costs were the occurrence of stroke or systemic embolism, major bleeding, and minor bleeding. The costs predictors were comparable when limiting the analysis to patients that were anticoagulation naïve. Age and CHA₂DS₂-VASc were not predictors for either cardiology or total hospital care costs in both analyses.

CONCLUSION

Dabigatran treatment was as a predictor for lower cardiology costs and lower total hospital care costs in AF patients that initiated oral anticoagulation.

Implementation and Evaluation of an Economic Model for Telestroke: Experience from Virtuall, France

Background

Telestroke is recognized as a safe and time-efficient way of treating stroke patients. However, admission centers (spokes) are subject to financial charges which can make them reluctant to join the system. We implemented and assessed an economic model supporting our telestroke system, Virtuall, France, which includes one expert center (hub) and six spokes.

Methods

The model is based on payment for the expertise provided by the hub, distribution of charges related to telemedicine according to the fees perceived by the spokes, and transfer of patients between the spokes and the hub. We performed a cost–benefit analysis for all patients included in Virtuall from January 2014 to December 2015 to assess the economic balance in each center.

Results

321 patients were prospectively included in the study. Application of the economic model resulted in overall financial balance with funding of a dedicated medical service in the hub, and reduced costs directly related to telestroke by an average of 10% in the spokes. The conditions generating the highest costs for the spokes were: a patient returning from the hub for re-hospitalization (mean cost of $1,995/patient); management of patients treated by intravenous thrombolysis without transfer to the hub (mean cost of $2,075/patient). The most favorable financial condition for the spokes remained simple transfer of patients to the hub and no return (mean cost of $329/patient).

Conclusion

We describe an economic model which can be applied to any telestroke system to ensure the optimal balance between hub and spoke centers.

Predictive ability of HAS-BLED, HEMORR2HAGES, and ATRIA bleeding risk scores in patients with atrial fibrillation. A French nationwide cross-sectional study

OBJECTIVE

The HAS-BLED, ATRIA, and HEMORR2HAGES risk scores were created to evaluate individual bleeding risk in atrial fibrillation (AF). We sought to estimate and compare the predictive ability of these scores for major hemorrhage in AF, including elderly (≥80years) and non-elderly (<80years) patients.

METHODS

This cross-sectional study is based on the French National Hospital Database (PMSI), which covers the entire French population. Data from all patients with an AF diagnosis in 2012 were extracted. Demographic and comorbidity data were used to calculate the three bleeding risk scores for each patient. Patients hospitalized with a principal diagnosis of major bleeding were identified.

RESULTS

Of the 533,044 AF patients identified, 53.2% were ≥80years; 7013 patients (1.3%) were hospitalized for a bleeding event (1785 for intracranial hemorrhage). Bleeding occurred more frequently in patients with higher HAS-BLED, HEMORR2HAGES, and ATRIA scores. In patients ≥80years, the c-statistics did not differ (p=0.27) between HAS-BLED (0.54; 95% confidence interval [CI]: 0.53-0.54), HEMORR2HAGES (0.53; 95% CI: 0.53-0.54), and ATRIA (0.53; 95% CI: 0.52-0.54). In patients <80years, HAS-BLED (0.59; 95% CI: 0.58-0.60) had a slightly higher c-statistic than HEMORR2HAGES (0.56; 95% CI: 0.55-0.57) and ATRIA (0.55, 95% CI: 0.55-0.56) (p<0.0001).

CONCLUSIONS

Given its simplicity and similar performance, HAS-BLED may be an attractive alternative to HEMORR2HAGES for estimation of bleeding risk in AF patients <80years. However, accurate determination of bleeding risk among the elderly is difficult with existing risk-prediction scores, indicating a clear need for improvement in their clinical utility.