Does atrial fibrillation affect prognosis in hospitalised COVID-19 patients? A multicentre historical cohort study in the Netherlands.

OBJECTIVES: The aim of this multicentre COVID-PREDICT study (a nationwide observational cohort study that aims to better understand clinical course of COVID-19 and to predict which COVID-19 patients should receive which treatment and which type of care) was to determine the association between atrial fibrillation (AF) and mortality, intensive care unit (ICU) admission, complications and discharge destination in hospitalised COVID-19 patients. SETTING: Data from a historical cohort study in eight hospitals (both academic and non-academic) in the Netherlands between January 2020 and July 2021 were used in this study. PARTICIPANTS: 3064 hospitalised COVID-19 patients >18 years old. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was the incidence of new-onset AF during hospitalisation. Secondary outcomes were the association between new-onset AF (vs prevalent or non-AF) and mortality, ICU admissions, complications and discharge destination, performed by univariable and multivariable logistic regression analyses. RESULTS: Of the 3064 included patients (60.6% men, median age: 65 years, IQR 55-75 years), 72 (2.3%) patients had prevalent AF and 164 (5.4%) patients developed new-onset AF during hospitalisation. Compared with patients without AF, patients with new-onset AF had a higher incidence of death (adjusted OR (aOR) 1.71, 95% CI 1.17 to 2.59) an ICU admission (aOR 5.45, 95% CI 3.90 to 7.61). Mortality was non-significantly different between patients with prevalent AF and those with new-onset AF (aOR 0.97, 95% CI 0.53 to 1.76). However, new-onset AF was associated with a higher incidence of ICU admission and complications compared with prevalent AF (OR 6.34, 95% CI 2.95 to 13.63, OR 3.04, 95% CI 1.67 to 5.55, respectively). CONCLUSION: New-onset AF was associated with an increased incidence of death, ICU admission, complications and a lower chance to be discharged home. These effects were far less pronounced in patients with prevalent AF. Therefore, new-onset AF seems to represent a marker of disease severity, rather than a cause of adverse outcomes.

Prevalence and Predictors of Nonadherence to Direct Oral Anticoagulant Treatment in Patients with Atrial Fibrillation.

Background For most patients with newly diagnosed atrial fibrillation (AF), direct oral anticoagulants (DOACs) are preferred over vitamin K antagonists. However, there is concern that the lack of monitoring may impair therapy adherence and therefore the anticoagulant effect. Objective To assess 1-year DOAC nonadherence in patients with AF and a treatment indication of at least 1 year in the Dutch health care setting, and to identify predictors of nonadherence. Methods We performed a near-nationwide historical cohort study in patients with a novel DOAC indication for AF. Data were obtained from a pharmacy database, covering 65% of all outpatient prescriptions dispensed in the Netherlands. The 1-year nonadherence was assessed by the proportion of days covered; the threshold was set at <80%. Robust Poisson regression analyses were performed to identify predictors of nonadherence. Results A total of 46,211 patients were included and the 1-year nonadherence was 6.5%. We identified male sex (risk ratio [RR] 1.23, 95% confidence interval [CI]: 1.15-1.33), younger age (age ≥60 to <70 years: RR: 1.15, 95% CI: 1.00-1.33, age <60 years: RR: 2.22, 95% CI: 1.92-2.57; reference age ≥85 years), a reduced DOAC dose (RR: 1.10, 95% CI: 1.00-1.22), a twice-daily dosing regimen (RR: 1.21, 95% CI: 1.12-1.30), and treatment with apixaban (RR: 1.16, 95% CI: 1.06-1.26, reference rivaroxaban) or dabigatran (RR: 1.25, 95% CI: 1.14-1.37) as independent predictors of 1-year nonadherence. Conclusion One-year nonadherence to DOACs was low yet relevant in patients with AF newly prescribed a DOAC. Understanding the predictors for nonadherence may help identify patients at risk.

Atrial epicardial adipose tissue abundantly secretes myeloperoxidase and activates atrial fibroblasts in patients with atrial fibrillation.

BACKGROUND: Epicardial adipose tissue (EAT) secretome induces fibrosis. Fibrosis, primarily extracellular matrix (ECM) produced by fibroblasts, creates a substrate for atrial fibrillation (AF). Whether the EAT secretome from patients with AF activates human atrial fibroblasts and through which components, remains unexplored. RESEARCH AIMS: (a) To investigate if the EAT secretome from patients with versus without AF increases ECM production in atrial fibroblasts. (b) To identify profibrotic proteins and processes in the EAT secretome and EAT from patients with, who will develop (future onset), and without AF. METHODS: Atrial EAT was obtainded during thoracoscopic ablation (AF, n = 20), or open-heart surgery (future onset and non-AF, n = 35). ECM gene expression of human atrial fibroblasts exposed to the EAT secretome and the proteomes of EAT secretome and EAT were assessed in patients with and without AF. Myeloperoxidase and neutrophil extracellular traps (NETs) were assessed immunohistochemically in patients with paroxysmal, persistent, future onset, and those who remain free of AF (non-AF). RESULTS: The expression of COL1A1 and FN1 in fibroblasts exposed to secretome from patients with AF was 3.7 and 4.7 times higher than in patients without AF (p < 0.05). Myeloperoxidase was the most increased protein in the EAT secretome and EAT from patients with versus without AF (FC 18.07 and 21.57, p < 0.005), as was the gene-set neutrophil degranulation. Immunohistochemically, myeloperoxidase was highest in persistent (FC 13.3, p < 0.0001) and increased in future onset AF (FC 2.4, p = 0.02) versus non-AF. Myeloperoxidase aggregated subepicardially and around fibrofatty infiltrates. NETs were increased in patients with persistent versus non-AF (p = 0.03). CONCLUSION: In AF, the EAT secretome induces ECM gene expression in atrial fibroblasts and contains abundant myeloperoxidase. EAT myeloperoxidase was increased prior to AF onset, and both myeloperoxidase and NETs were highest in persistent AF, highlighting the role of EAT neutrophils in the pathophysiology of AF.

Women Have More Recurrences of Atrial Fibrillation than Men after Thoracoscopic Ablation and Suffer More from Established Risk Factors.

INTRODUCTION: Atrial fibrillation (AF) is more prevalent in men than in women. However, women with AF are more symptomatic, have a worse quality of life, a higher stroke risk and may therefore benefit most from ablation. In this study we aim to identify the risk of recurrent AF after thoracoscopic ablation, and assess the differential impact of the risk factors for recurrence between women and men. METHOD: This is a single center cohort study, including patients undergoing thoracoscopic ablation for advanced AF between 2008 and 2019. All patients were clinically followed up for two years with quarterly 24 h Holter monitoring and ECGs for the detection of recurrent AF. Left atrial appendage (LAA) tissue was collected for collagen analysis. RESULTS: We included 571 patients, of whom 143 (25%) were women. Women were older than men (63 ± 8.3 y vs. 59 ± 8.5, p < 0.001), but had fewer cardiovascular risk factors, myocardial infarctions (1.4% vs. 6.5%, p = 0.03) and, in particular, vascular disease (7.0% vs. 16.1%, p = 0.01). Women suffered more from AF recurrence, driven by more atrial tachycardias, and sex was an independent risk factor for recurrence (HR1.41 [1.04-1.91], p = 0.028]). The presence of vascular disease was associated with an increased risk for AF recurrence in women, but not in men. In LAA histology, women had more collagen than men, as had patients with persistent compared to paroxysmal AF. CONCLUSION: Women had 15% more recurrences, driven by more atrial tachycardias, which may be explained by a more fibrotic atrial substrate. What's new? Women undergoing thoracoscopic AF ablation have a higher risk of recurrent AF, driven by more atrial tachycardias. Among patients with left atrial enlargement or persistent AF, women have worse outcomes than men. Vascular disease was a risk factor for recurrence in women, but not in men. In a histopathologic analysis of the left atrial appendage, women had more collagen than men, as had patients with persistent compared to paroxysmal AF.

Clinical Studies with Anticoagulants that Have Changed Clinical Practice.

Anticoagulant therapy is the cornerstone of treatment and prevention of arterial and venous thromboembolism. Taking a historical perspective, starting in the 1960s, and progressing through to 2022, we discuss key clinical trials of anticoagulants that have changed clinical practice, and examine obstacles encountered in bringing these anticoagulants to the clinic. The design of some of the early studies that shaped clinical practice was poor by current standards, but their results were influential because nothing better was available. Both heparin and vitamin K antagonists had been in clinical use for several decades before well-designed trials in the 1980s optimized their dosing and enhanced their safety and efficacy. Low-molecular-weight heparin then replaced unfractionated heparin because it had a more predictable dose-response and a longer half-life, thereby allowing it to be used conveniently in out-of-hospital settings. More recently, direct oral anticoagulants became the oral anticoagulants of choice for most indications because they were shown to be at least as safe and effective as vitamin K antagonists when used in fixed doses without the need for laboratory monitoring. The design of the trials that led to the approval of the direct oral anticoagulants was excellent, but further studies are required to optimize their dosing in selected patients who were underrepresented in these trials.

A failed catheter ablation of atrial fibrillation is associated with more advanced remodeling and reduced efficacy of further thoracoscopic ablation.

INTRODUCTION AND OBJECTIVES: Recent observations suggest that patients with a previous failed catheter ablation have an increased risk of atrial fibrillation (AF) recurrence after subsequent thoracoscopic AF ablation. We assessed the risk of AF recurrence in patients with a previous failed catheter ablation undergoing thoracoscopic ablation. METHODS: We included patients from 3 medical centers. To correct for potential heterogeneity, we performed propensity matching to compare AF freedom (freedom from any atrial tachyarrhythmia> 30 s during 1-year follow-up). Left atrial appendage tissue was analyzed for collagen distribution. RESULTS: A total of 705 patients were included, and 183 had a previous failed catheter ablation. These patients had fewer risk factors for AF recurrence than ablation naïve controls: smaller indexed left atrial volume (40.9± 12.5 vs 43.0±12.5 mL/m2, P=.048), less congestive heart failure (1.5% vs 8.9%, P=.001), and less persistent AF (52.2% vs 60.3%, P=.067). However, AF history duration was longer in patients with a previous failed catheter ablation (6.5 [4-10.5] vs 4 [2-8] years; P<.001). In propensity matched analysis, patients with a failed catheter ablation were at a 68% higher AF recurrence risk (OR, 1.68; 95%CI, 1.20-2.15; P=.034). AF freedom was 61.1% in patients with a previous failed catheter ablation vs 72.5% in ablation naïve matched controls. On histology of the left atrial appendage (n=198), patients with a failed catheter ablation had a higher density of collagen fibers. CONCLUSIONS: Patients with a prior failed catheter ablation had fewer risk factors for AF recurrence but more frequently had AF recurrence after thoracoscopic AF ablation than ablation naïve patients. This may in part be explained by more progressed, subclinical, atrial fibrosis formation.

Circulating adipose tissue proteins involved in atrial fibrillation: An explorative scoping review.

Obesity increases the risk of atrial fibrillation (AF), potentially through proteins secreted by adipose tissue (AT) that affect atrial electrical and structural remodeling. We aim to give a comprehensive overview of circulating AT proteins involved in inflammation and fibrosis, that are associated with prevalent AF (paroxysmal or persistent) and the risk on developing new-onset AF. These include adipokines, defined as proteins enriched in AT as adiponectin, but also proteins less specific to AT. We systematically performed an explorative search for studies reporting associations between proteins secreted from cells residing in the AT and AF, and additionally assessed the effect of obesity on these proteins by a secondary search. The AT proteins involved in inflammation were mostly increased in patients with prevalent and new-onset AF, and with obesity, while the AT enriched adipokines were mostly not associated with AF. This review provides insight into circulating adipose tissue proteins involved in AF substrate formation.

Inflammation as a Mechanism and Therapeutic Target in Peripheral Artery Disease.

Peripheral artery disease is 1 of 3 major clinical manifestations of atherosclerosis, the other 2 being coronary artery and cerebrovascular disease. Despite progress in surgery, antithrombotic therapy and therapies that modify conventional risk factors (lipid-, blood pressure-, and glucose-lowering interventions), patients with peripheral artery disease have an unacceptably high risk of vascular complications. Additional strategies to reduce this residual risk are needed. The accumulated evidence that inflammation plays an important role in the pathogenesis of atherosclerosis has spurred recent efforts to evaluate anti-inflammatory agents as an additional therapeutic approach for atherothrombosis prevention and treatment. In this review, we examine the evidence supporting the role of inflammation in atherosclerosis, review recent trials of anti-inflammatory approaches to reduce cardiovascular complications, and offer insights into the opportunities for novel anti-inflammatory strategies to reduce the burden of cardiovascular and limb complications in patients with peripheral artery disease.

Can a Single Measurement of Apixaban Levels Identify Patients at Risk of Overexposure? A Prospective Cohort Study.

Background Patients with atrial fibrillation (AF) are frequently treated with apixaban 2.5-mg twice daily (BID) off-label, presumably to reduce the bleeding risk. However, this approach has the potential to increase the risk of ischemic stroke. If a single measurement could reliably identify patients with high drug levels, the increased stroke risk may be mitigated by confining off-label dose reduction to such patients. Objectives This study aimed to determine whether a single high apixaban level is predictive of a similarly high level when the test is repeated in 2 months. Methods In this prospective cohort study of clinic patients receiving apixaban 5-mg BID for AF or venous thromboembolism, peak and trough apixaban levels were measured using the STA-Liquid anti-Xa assay at baseline and 2 months. We calculated the proportions of patients with levels that remained in the upper quintile. Results Of 100 enrolled patients, 82 came for a second visit, 55 of whom were treated with apixaban 5-mg BID. Seven (63.6%, 95% confidence interval [CI]: 35.4-84.8%) and nine (81.8%, 95% CI: 52.3-94.9%) of 11 patients with a baseline trough and peak level in the upper quintile, respectively, had a subsequent level that remained within this range. Only one (9.1%, 95% CI: 1.6-37.7%) patient had a subsequent level that fell just lower than the median. Conclusion The trough and peak levels of apixaban in patients who have a high level on a single occasion, usually remain high when the assay is repeated in 2 months. Accordingly, the finding of a high apixaban level in patients deemed to be at high risk of bleeding, allows physicians contemplating off-label use of the 2.5-mg BID dose to limit its use to selected patients who are less likely to be exposed to an increased risk of thrombosis.

Dual pathway inhibition for atherosclerotic cardiovascular disease: Recent advances.

Atherosclerotic cardiovascular disease (ASCVD), which includes coronary artery disease (CAD), cerebrovascular disease, and peripheral arterial disease (PAD) is associated with significant morbidity, mortality, and healthcare costs. Antiplatelet therapy has long been the mainstay of antithrombotic therapy for the prevention of first-ever and recurrent ASCVD events. More recently, however, randomized trials have demonstrated the benefits and cost-effectiveness of a dual pathway inhibition (DPI) strategy in acute and chronic ASCVD. When used in combination, aspirin and low-dose rivaroxaban work synergistically to inhibit platelet activation and thrombin generation, thereby preventing thrombus formation. Among patients with recent acute coronary syndrome (ACS), those with positive cardiac biomarkers or ST-segment elevation myocardial infarction, or a history of heart failure derive the greatest absolute benefits. Among patients with chronic ASCVD, those with involvement of two or more vascular beds, heart failure, chronic kidney disease, or diabetes derive the greatest absolute benefits. Additional trials are underway to assess the impact of DPI therapy in other populations of interest, including patients with ACS at high risk of left ventricular thrombus formation, intracranial atherosclerotic disease with recent transient ischemic attack or stroke, peripheral arterial disease with limiting claudication or post lower extremity revascularization, and advanced chronic kidney disease with ASCVD or risk factors for ASCVD. Further work is required to assess the possible added benefit of combining rivaroxaban with clopidogrel or ticagrelor instead of aspirin.

Characteristics of patients with atrial fibrillation prescribed edoxaban in Belgium and The Netherlands: insights from the ETNA-AF-Europe study.

BACKGROUND: Studies on the use of non-vitamin K antagonist oral anticoagulants in unselected patients with atrial fibrillation (AF) show that clinical characteristics and dosing practices differ per region, but lack data on edoxaban. METHODS: With data from Edoxaban Treatment in routiNe clinical prActice for patients with AF in Europe (ETNA-AF-Europe), a large prospective observational study, we compared clinical characteristics (including the dose reduction criteria for edoxaban: creatinine clearance 15-50 mL/min, weight ≤60 kg, and/or use of strong p-glycoprotein inhibitors) of patients from Belgium and the Netherlands (BeNe) with those from other European countries (OEC). RESULTS: Of all 13,639 patients in ETNA-AF-Europe, 2579 were from BeNe. BeNe patients were younger than OEC patients (mean age: 72.3 vs 73.9 years), and had lower CHA2DS2-VASc (mean: 2.8 vs 3.2) and HAS-BLED scores (mean: 2.4 vs 2.6). Patients from BeNe less often had hypertension (61.6% vs 80.4%), and/or diabetes mellitus (17.3% vs 23.1%) than patients from OEC. Moreover, relatively fewer patients in BeNe were prescribed the reduced dose of 30 mg edoxaban (14.8%) than in OEC (25.4%). Overall, edoxaban was dosed according to label in 83.1% of patients. Yet, 30 mg edoxaban was prescribed in the absence of any dose reduction criteria in 36.9% of 30 mg users (5.5% of all patients) in BeNe compared with 35.5% (9.0% of all patients) in OEC. CONCLUSION: There were several notable differences between BeNe and OEC regarding clinical characteristics and dosing practices in patients prescribed edoxaban, which are relevant for the local implementation of dose evaluation and optimisation. TRIAL REGISTRATION: NCT02944019; Date of registration: October 24, 2016.

Apixaban for Stroke Prevention in Atrial Fibrillation: Why are Event Rates Higher in Clinical Practice than in Randomized Trials?-A Systematic Review.

BACKGROUND: Recent reports suggest an important contribution from frequent off-label use of apixaban 2.5 mg twice daily to the higher rates of thromboembolic events observed in observational studies (OSs) relative to in randomized controlled trials (RCTs), and consequently, advocate against such use in all patients. OBJECTIVES: To examine factors contributing to the higher thromboembolic event rates, we estimated the prevalence of off-label use in contemporary practice, and compared patient characteristics and rates of stroke/systemic embolism, major bleeding, and mortality by apixaban dose and by study design in a systematic review and meta-analysis. RESULTS AND DISCUSSION: We identified 18 OSs and 2 RCTs that included 155,228 and 11,928 patients, respectively. Patients in OSs more often received apixaban 2.5 mg twice daily (31.3% vs. 5.1%), were older (mean age 73.8 vs. 69.8 years), and had higher CHA2DS2-VASc scores (mean 3.6 vs. 2.9) versus those in RCTs. We observed a consistent pattern of higher rates of thromboembolic events, bleeding, and mortality in patients treated with 2.5 versus 5 mg twice daily apixaban in both OSs and RCTs. CONCLUSION: The higher risk profiles of patients in OSs versus RCTs, and higher rates of both bleeding and mortality not attributable to thromboembolism in patients treated with apixaban 2.5 versus 5 mg twice daily suggest that differences in patient characteristics are additional important contributors to the higher than expected thromboembolic event rates in clinical practice.

In Vitro Reversal of the Anti-Aggregant Effect of Ticagrelor Using Untreated Platelets.

BACKGROUND: Ticagrelor is an anti-platelet agent that is indicated for prevention of thrombosis after acute coronary syndrome or intra-coronary artery stent implantation, but it increases the risk of bleeding. Platelet transfusion has the potential to treat or prevent bleeding in patients taking ticagrelor, but the optimal quantity of platelets and timing of administration have not been fully defined. METHODS AND RESULTS: Ten healthy subjects took ticagrelor in combination with acetylsalicylic acid for 5 days, and had blood collected prior to treatment and at 2, 10, 24, 48, 72 and 96 hours after the last doses. The potential of platelet transfusion to prevent or reverse bleeding was evaluated by mixing subject and donor platelet-rich plasma in vitro in nine different proportions, and measuring adenosine diphosphate-mediated aggregation by light transmission aggregometry. Spontaneous offset of the anti-aggregant effect of ticagrelor occurred gradually and was complete at 72 hours after the last dose. The addition of donor platelets enhanced the recovery. The addition of the equivalent of six apheresis platelet units produced a 50% relative reversal at 10 hours, and > 90% reversal at 24 hours. CONCLUSION: Donor platelets enhance reversal of the anti-aggregant effect of ticagrelor in vitro. Donor platelets given in clinically relevant amounts partially reversed ticagrelor at 10 hours after the last dose, and almost fully reversed ticagrelor at 24 hours. The results inform on the potential to reverse ticagrelor in patients who develop bleeding or require emergency surgery.