Predicting Thromboembolic and Bleeding Event Risk in Patients with Non-Valvular Atrial Fibrillation: A Systematic Review

Machine learning approach for prediction of outcomes in anticoagulated patients with atrial fibrillation

BACKGROUND

The accuracy of available prediction tools for clinical outcomes in patients with atrial fibrillation (AF) remains modest. Machine Learning (ML) has been used to predict outcomes in the AF population, but not in a population entirely on anticoagulant therapy.

METHODS AND AIMS

Different supervised ML models were applied to predict all-cause death, cardiovascular (CV) death, major bleeding and stroke in anticoagulated patients with AF, processing data from the multicenter START-2 Register.

RESULTS

11078 AF patients (male n = 6029, 54.3%) were enrolled with a median follow-up period of 1.5 years [IQR 1.0-2.6]. Patients on Vitamin K Antagonists (VKA) were 5135 (46.4%) and 5943 (53.6%) were on Direct Oral Anticoagulants (DOAC). Using Multi-Gate Mixture of Experts, a cross-validated AUC of 0.779 ± 0.016 and 0.745 ± 0.022 were obtained, respectively, for the prediction of all-cause death and CV-death in the overall population. The best ML model outperformed CHA2DSVA2SC and HAS-BLED for all-cause death prediction (p < 0.001 for both). When compared to HAS-BLED, Gradient Boosting improved major bleeding prediction in DOACs patients (0.711 vs. 0.586, p < 0.001). A very low number of events during follow-up (52) resulted in a suboptimal ischemic stroke prediction (best AUC of 0.606 ± 0.117 in overall population). Body mass index, age, renal function, platelet count and hemoglobin levels resulted the most important variables for ML prediction.

CONCLUSIONS

In AF patients, ML models showed good discriminative ability to predict all-cause death, regardless of the type of anticoagulation strategy, and major bleeding on DOAC therapy, outperforming CHA2DS2VASC and the HAS-BLED scores for risk prediction in these populations.

DOACs for Older adults with Atrial Fibrillation and Falls: Results from the prospective single-centre DOAFF study

INTRODUCTION

Falls are one of the most fearsome events in anticoagulated older adults. The evidence concerning safety of direct oral anticoagulants (DOACs) in falling elderly patients with atrial fibrillation (AF) is still limited.

METHODS

We prospectively enrolled consecutive anticoagulant-naïve patients aged 65 years and older, starting anticoagulation with DOACs for AF. The study cohort was stratified in fallers vs. non-fallers, according to the occurrence of at least one fall during the 2-year follow-up and bleeding outcomes were evaluated.

RESULTS

We enrolled 524 consecutive patients. Mean age was 80.8 years and they were mostly women (54.0%). Among the study cohort, 148 patients (28.2%) presented at least one fall episode during the study period. After the adjustment for potential confounders, no difference was found between fallers and non-fallers for all the study outcomes: major bleeding [HR: 1.04 (95%CI: 0.58-1.85)], intracranial haemorrhage [HR: 1.63 (95%CI: 0.69-3.80)], clinically relevant non-major bleeding [HR: 1.21 (95%CI: 0.83-1.76)], and all-cause death [HR: 1.51 (95%CI: 0.85-2.69)]. The presence of a prior cerebrovascular event [HR: 2.27 (95%CI: 1.12-4.62); p-value: 0.02] and polypharmacy [HR: 1.60 (95%CI: 1.08-2.39); p-value: 0.02] were the main drivers for major and clinically relevant non-major bleedings, respectively.

CONCLUSIONS

Falls in an anticoagulant-naïve population aged 65 years and over starting a DOAC for AF do not increase the bleeding risk. Thus, the presence of falls should not discourage clinicians from prescribing DOACs also in this subset of patients.

Comparing the Real-World and Clinical Trial Bleeding Rates Associated with Oral Anticoagulation Treatment for Atrial Fibrillation

Background The prevention of stroke in patients with atrial fibrillation (AF) involves the use of oral anticoagulation, commonly in the form of direct oral anticoagulants (DOACs). However, it comes with an increased risk of bleeding, and therefore, counselling patients on their individual risks is important. Although the majority of patients initiated on DOACs have been represented within the clinical trials, some cohorts are under-represented in whom clinicians cannot practice evidence-based medicine. Methods Utilising the pooled clinical trial (CT) data sourced from Medidata Enterprise Data Store, five recent open-label industry-sponsored AF trials were compared with real-world data (RWD) sourced from the HealthVerity™ Marketplace with the occurrence of bleeding events as the primary outcome of interest. Results A total of 64,421 patients were included in the analysis, with 3207 patients from the clinical DOAC trials and 61,214 patients from the RWD cohort. Overall, the patients from the RWD cohort had more co-morbidities, were older (72.2 ± 11.9 vs. 65.3 ± 10.7 years old, p < 0.001), had higher mean CHA2DS2VASc (3.98 ± 1.9 vs. 2.87 ± 1.73, p < 0.001), and HAD-BLED scores (2.13 ± 1.02 vs. 1/04 ± 0.93, p < 0.001) when compared to the trial data. When comparing the incidence of the first major bleed at 12 months post-treatment initiation, rates in the RWD cohort were significantly higher (10.69 vs. 18.97 per 100 person-years). The impact of co-morbidities such as age, CHA2DS2VASc, and HAD-BLED scores was similar in both cohorts; however, there was an under-representation of older females and more co-morbid patients within the clinical trial cohort. Conclusions DOAC-treated patients have a higher bleeding incidence rate in the RWD cohort than in clinical trials. This can be explained by the older patient age group with more complex medical h istories and higher HAS-BLED scores. The under-representation of higher-risk patients and lower proportion of females within clinical trials should be addressed to better translate clinical trial data into real-world clinical practice.

Atherothrombotic and thrombolytic biomarkers in incident stroke and atrial fibrillation-related stroke: The Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND AND AIMS

Although several biomarkers have been studied in thromboembolic stroke, measuring the balance between thrombus formation and thrombolysis and data on its role in predicting stroke and atrial fibrillation (AF)-related stroke is limited. We sought to assess atherothrombotic biomarkers grouped into composite factors that reflect thrombotic and thrombolytic potential, and the balance between these factors as it relates to incident stroke or transient ischemic attack (TIA) and stroke/TIA in AF.

METHODS

A Thrombotic Factor, derived from fibrinogen, plasmin-antiplasmin complex, factor VIII, D-dimer, and lipoprotein(a); and a Thrombolytic Factor, derived from plasminogen and oxidized phospholipids on plasminogen, were evaluated at baseline in 5,764 Multi-Ethnic Study of Atherosclerosis (MESA) participants. We evaluated the association between these two factors representative of thrombotic and thrombolytic potential and incident stroke/TIA (n = 402), and AF-related stroke/TIA (n = 82) over a median of 13.9 and 3.7 years, respectively. Cox proportional hazard models adjusted for medication use, cardiovascular risk factors and CHA2DS2-VASc score were utilized. Harrell's C-index was estimated to evaluate model performance.

RESULTS

In models including both factors, Thrombotic Factor was positively while Thrombolytic Factor was inversely associated with incident stroke/TIA and AF-related stroke/TIA. Incorporating these factors along with the CHA2DS2-VASc in adjusted models resulted in a small improvement in risk prediction of incident stroke/TIA and AF-related stroke/TIA compared to models without the factors (C-index from 0.697 to 0.704, and from 0.657 to 0.675, respectively).

CONCLUSIONS

Composite biomarker factors, representative of the balance between thrombotic and thrombolytic propensity, provided an improvement in predicting stroke/TIA beyond CHA2DS2-VASc score.

Oral anticoagulant safety in family practice: prognostic accuracy of Bleeding Risk Scores (from the CACAO study)

BACKGROUND

To assess bleeding risk of patients treated by oral anticoagulants, several scores have been constructed to assist physicians in the evaluation of the benefit risk. Most of these scores lack a strong enough level of evidence for use in family practice.

OBJECTIVE

To assess the predictive prognostic accuracy of 13 scores designed to assess the risk of major or clinically relevant non-major (CRNM) bleeding events in a French ambulatory cohort receiving Vitamin-K antagonists (VKA) or direct oral anticoagulants (DOACs) in a family practice setting.

METHODS

CACAO (Comparison of Accidents and their Circumstances with Oral Anticoagulants) was a multicentre prospective cohort of ambulatory patients prescribed oral anticoagulants. We selected patients from the cohort who had received an oral anticoagulant because of non-valvular atrial fibrillation (NVAF) and/or venous thromboembolism (VTE) to be followed during one year by their GP. The following scores were calculated: mOBRI, Shireman, Kuijer, HEMORR2HAGES, ATRIA, HAS-BLED, RIETE, VTE-BLEED, ACCP score, Rutherford, ABH-Score, GARFIEL-AF, and Outcomes Registry for Better InformedTreatment of Atrial Fibrillation (ORBIT). Prognostic accuracy was assessed by using receiver operating characteristic curves and c-statistics.

RESULTS

During 1 year, 3,082 patients were followed. All of the scores demonstrated only poor to moderate ability to predict major bleeding or CRNM in NVAF patients on DOACs (c-statistic: 0.41-0.66 and 0.45-0.58), respectively. The results were only slightly better for patients prescribed VKA (0.47-0.66 and 0.5-0.55, respectively) in this indication. The results were also unsatisfactory in patients treated for VTE.

CONCLUSION

None of the scores demonstrated satisfactory discriminatory ability when used in family practice.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT02376777.

Review of the National Institute for Health and Care Excellence guidelines on the management of atrial and ventricular arrhythmias

The National Institute for Health and Care Excellence (NICE) guidelines present a synopsis of extensive internal evidence and technology reviews, with a particular focus on clinical efficacy and cost-effectiveness within the NHS in England. This approach has delivered a novel perspective on arrhythmia management, with important distinctions from other policymakers' recommendations. For example, when compared with the European Society of Cardiology (ESC) and the American Heart Association (AHA)/Heart Rhythm Society (HRS)/American College of Cardiology (ACC) guidelines on atrial fibrillation (AF), NICE advocates unique strategies regarding arrhythmia detection, stroke and bleeding risk stratification, and rhythm control (NICE CG 196). Likewise, for patients at risk of sudden cardiac death, NICE TA314 not only recommends device therapy based on New York Heart Association class and ECG findings, but also incorporates quality-adjusted life year data from analysis of key randomised controlled trials.This review examines the NICE guidelines, together with those from the AHA/HRS/ACC and ESC, on the management of AF and ventricular arrhythmias and highlights the key common features and discrepancies between these important documents.

Atrial fibrillation: stroke prevention

Stroke prevention is central to the management of patients with atrial fibrillation (AF) which has moved towards a more holistic or integrative care approach. The published evidence suggests that management of AF patients following such a holistic approach based on the Atrial fibrillation Better Care (ABC) pathway is associated with a lower risk of stroke and adverse events. Risk assessment, re-assessment and use of direct oral anticoagulants (DOACs) are important for stroke prevention in AF. The stroke and bleeding risks of AF patients are not static and should be re-assessed regularly. Bleeding risk assessment is to address and mitigate modifiable bleeding risk factors, and to identify high bleeding risk patients for early review and follow-up. Well-controlled comorbidities and healthy lifestyles also play an important role to achieve a better clinical outcome. Digital health solutions are increasingly relevant in the diagnosis and management of patients with AF, with the potential to improve stroke prevention. In this review, we provide an update on stroke prevention in AF, including importance of holistic management, risk assessment/re-assessment, and stroke prevention for special AF populations. Evidence-based and structured management of AF patients would reduce the risk of stroke and other adverse events.

Development and Validation of a New Nomogram Model for Predicting Acute Ischemic Stroke in Elderly Patients with Non-Valvular Atrial Fibrillation: A Single-Center Cross-Sectional Study

Background and Aims

Non-valvular atrial fibrillation (NVAF) patients face a 3-5 times greater risk of acute ischemic stroke (AIS) compared to those without NVAF. This study aims to establish a novel clinical prediction model for AIS in elderly patients with NVAF by incorporating relevant biomarker indicators.

Methods

A total of 301 individuals diagnosed with NVAF were selected for this investigation at the Third Affiliated Hospital of Anhui Medical University. Based on the presence of AIS, patients were categorized into two groups: the Stroke Cohort and the Non-Stroke Cohort. Predictor screening was performed using the least absolute shrinkage and selection operation (LASSO) regression algorithm. The binary logistic regression equation was applied to fit the model, followed by internal validation using the bootstrap resampling method (1000 times). Receiver operating characteristic (ROC) curve, calibration degree curve plots, and clinical decision curve analysis (DCA) were generated, respectively. Finally, a nomogram was constructed to present the prediction model.

Results

The final results of this study revealed that neutrophil-to-lymphocyte ratio (NLR), red cell distribution width (RDW), lipoprotein(a) (Lp(a)), systolic pressure, history of stroke, hyperlipidemia were independent risk factors for AIS in elderly patients with NVAF (P<0.05). And the high-density lipoprotein cholesterol (HDL-C) was an independent protective factor (P<0.05). By incorporating these indicators, a nomogram prediction model for predicting AIS in elderly patients with NVAF was constructed. Comparative analysis between the nomogram predictive model and CHA2DS2-VASc score revealed that the AUC of the nomogram predictive model surpassed that of the CHA2DS2-VASc score (AUC: 0.881vs 0.850).

Conclusion

NLR, RDW, Lp(a), SP, history of stroke, hyperlipidemia, and HDL-C emerge as independent prognostic factors for acute ischemic stroke in elderly patients with non-valvular atrial fibrillation. The predictive utility of the nomogram model may potentially surpass that of the CHA2DS2-VASc scoring system.

The importance of intensive follow-up and achieving optimal chronic antithrombotic treatment in hospitalized medical patients with anemia: A prospective cohort study

BACKGROUND

Anemia is a global health concern, particularly among the elderly on chronic antithrombotic treatment. Close monitoring of hemoglobin (Hb) levels and achievement of an optimized treatment significantly enhance patients' quality of life. This study aimed to examine the impact of antithrombotic treatment on Hb levels and readmissions in hospitalized patients with anemia.

METHODS

This is a prospective cohort study of patients admitted to the Department of Internal Medicine of the University Hospital of Heraklion, Greece, from November 2021 to October 2022 with the diagnosis of anemia while receiving antithrombotic treatment. Data regarding demographics, past medical history, and laboratory and endoscopy findings were recorded. For those receiving inappropriate therapy according to international guidelines, antithrombotic treatment was optimized. Subsequent follow-ups occurred at one and six months post-discharge. Six- and twelve-month anemia-caused readmissions, as well as annual mortality, were evaluated.

RESULTS

In total, 104 patients were assessed. Among them, 34.6% were on antiplatelets, 56.7% were on anticoagulants, and 8.7% were on combination treatment. The mean age was 80 ± 8.2 years, and 54.8% were males. On admission, mean Hb levels were 6.86 ± 1.23 g/dL, while 56 (53.8%) patients had severe anemia. Gastroscopy and colonoscopy were performed in 75.0% and 41.4% of patients, respectively, confirming gastrointestinal bleeding in most of the cases. Treatment optimization was carried out for 56 patients. Follow-up revealed elevated Hb levels after one and six months post-discharge, while anemia-related readmissions stayed below 10%.

CONCLUSIONS

Most hospitalized anemic patients on antithrombotic treatment had endoscopic findings favoring gastrointestinal bleeding. Half received inappropriate antithrombotic therapy. Treatment optimization and regular follow-up improved Hb levels and reduced readmissions.

Stroke in Patients with Atrial Fibrillation: Epidemiology, Screening, and Prognosis

Atrial fibrillation (AF) is the most common sustained arrythmia and one of the strongest risk factors and causal mechanisms of ischemic stroke (IS). Acute IS due to AF tends to be more severe than with other etiology of IS and patients with treated AF have reported to experience worse outcomes after endovascular treatment compared with patients without AF. As cardioembolism accounts for more than a fifth of ISs and the risk of future stroke can be mitigated with effective anticoagulation, which has been shown to be effective and safe in patients with paroxysmal or sustained AF, the screening of patients with cryptogenic IS (CIS) for AF is paramount. Embolic stroke of undetermined source (ESUS) is a subtype of CIS with a high likelihood of cardioembolism. The European Stroke Organization and European Society of Cardiology guidelines recommend at least 72 h of screening when AF is suspected. The longer the screening and the earlier the time point after acute IS, the more likely the AF paroxysm is found. Several methods are available for short-term screening of AF, including in-hospital monitoring and wearable electrocardiogram recorders for home monitoring. Implantable loop monitors provide an effective long-term method to screen patients with high risk of AF after IS and artificial intelligence and convolutional neural networks may enhance the efficacy of AF screening in the future. Direct oral anticoagulants (DOACs) are preferred over vitamin K antagonists in both primary and secondary prevention of IS in AF patients. Recent data from the randomized controlled trials (RCT) also suggest that early initiation of DOAC treatment after acute IS is safe compared to later initiation. Anticoagulation treatment may still predispose for intracranial bleeding, particularly among patients with prior cerebrovascular events. Left atrial appendix closure offers an optional treatment choice for patients with prior intracranial hemorrhage and may offer an alternative to oral anticoagulation even for patients with IS, but these indications await validation in ongoing RCTs. There are still controversies related to the association of found AF paroxysms in CIS patients with prolonged screening, pertaining to the optimal duration of screening and screening strategies with prolonged monitoring techniques in patients with ESUS. In this review, we summarize the current knowledge of epidemiology, screening, and prognosis in AF patients with stroke.

Hemorrhagic Coagulation Disorders and Ischemic Stroke: How to Reconcile Both?

Coagulation and fibrinolytic system disorders are conditions in which the blood's ability to clot is impaired, resulting in an increased risk of thrombosis or bleeding. Although these disorders are the expression of two opposing tendencies, they can often be associated with or be a consequence of each other, contributing to making the prognosis of acute cerebrovascular events more difficult. It is important to recognize those conditions that are characterized by dual alterations in the coagulation and fibrinolytic systems to reduce the prognostic impact of clinical conditions with difficult treatment and often unfortunate outcomes. Management of these individuals can be challenging, as clinicians must balance the need to prevent bleeding episodes with the potential risk of clot formation. Treatment decisions should be made on an individual basis, considering the specific bleeding disorder, its severity, and the patient's general medical condition. This review aims to deal with all those forms in which coagulation and fibrinolysis represent two sides of the same media in the correct management of patients with acute neurological syndrome. Precision medicine, personalized treatment, advanced anticoagulant strategies, and innovations in bleeding control represent future directions in the management of these complex pathologies in which stroke can be the evolution of two different acute events or be the first manifestation of an occult or unknown underlying pathology.

Prevention of cerebral thromboembolism by oral anticoagulation with dabigatran after pulmonary vein isolation for atrial fibrillation: the ODIn-AF trial

BACKGROUND AND OBJECTIVES

Long-term oral anticoagulation (OAC) following successful catheter ablation of atrial fibrillation (AF) remains controversial. Prospective data are missing. The ODIn-AF study aimed to evaluate the effect of OAC on the incidence of silent cerebral embolic events and clinically relevant cardioembolic events in patients at intermediate to high risk for embolic events, free from AF after pulmonary vein isolation (PVI).

METHODS

This prospective, randomized, multicenter, open-label, blinded endpoint interventional trial enrolled patients who were scheduled for PVI to treat paroxysmal or persistent AF. Six months after PVI, AF-free patients were randomized to receive either continued OAC with dabigatran or no OAC. The primary endpoint was the incidence of new silent micro- and macro-embolic lesions detected on brain MRI at 12 months of follow-up compared to baseline. Safety analysis included bleedings, clinically evident cardioembolic, and serious adverse events (SAE).

RESULTS

Between 2015 and 2021, 200 patients were randomized into 2 study arms (on OAC: n = 99, off OAC: n = 101). There was no significant difference in the occurrence of new cerebral microlesions between the on OAC and off OAC arm [2 (2%) versus 0 (0%); P = 0.1517] after 12 months. MRI showed no new macro-embolic lesion, no clinical apparent strokes were present in both groups. SAE were more frequent in the OAC arm [on OAC n = 34 (31.8%), off OAC n = 18 (19.4%); P = 0.0460]; bleedings did not differ.

CONCLUSION

Discontinuation of OAC after successful PVI was not found to be associated with an elevated risk of cerebral embolic events compared with continued OAC after a follow-up of 12 months.

Inflammation and Coagulation are Two Interconnected Pathophysiological Pathways in Atrial Fibrillation Pathogenesis

Introduction

Atrial fibrillation (AF) is associated with elevated levels of clotting factors such as tissue factor (TF) and factor XII (FXII). Various inflammation markers, such as interleukin-6 (IL-6), tumor necrosis factor-α (TNF- α), and high-sensitive C-reactive protein (hs-CRP), have also been associated with AF. This study explores the relationship between inflammation markers and coagulation activity, including their impact on heart structural changes in these patients.

Methods

We observed 283 patients with nonvalvular AF who underwent a complete examination at admission, but only 183 patients have successful cardioversion. As a control group, similar patients without AF were examined. The markers of the coagulation and inflammation were studied by ELISA on the analyzer "Stat Fax 303 Plus". Studies were conducted using l statistical package SPSS 13.0.

Results

It was revealed that patients with AF had significantly higher levels of hs-CRP, IL-6, and TNF-α and had elevated levels of TF and FXII compared with control group. The moderate correlations were observed between IL-6 and left atrial diameter (LAD), IL-6 and LA stiffness, hs-CRP and left atrial volume (LAV), TF and LAV.

Conclusion

We have demonstrated that patients with AF have the relationship between elevated levels of inflammatory markers and coagulation activity, which contributes to structural atrial remodeling.

Reduced-Dose Rivaroxaban Is Associated with Lower All-Cause Mortality in Older Patients with Nonvalvular Atrial Fibrillation

BACKGROUND

Reduced-dose rivaroxaban (10 mg) was used in the J-ROCKET AF trial, demonstrating safety in the Asian population. It remains unclear whether treatment with reduced-dose versus full-dose rivaroxaban (20 mg/15 mg) is associated with all-cause mortality in older patients with nonvalvular atrial fibrillation. Proposed: To evaluate the effects of reduced-dose rivaroxaban on all-cause mortality in patients over 85.

METHODS

We retrospectively enrolled medical records representing the period from October 2012 to November 2016. The 2 × 2 factorial design incorporated age (≥85 vs. <85) and rivaroxaban use (reduced vs. full dose). The primary study outcomes were all-cause and cardiac-related mortality.

RESULTS

The study enrolled 2386 patients with a mean age of 76.6 ± 10.4 years; 51.8% were male. In the ≥85 group (n = 593), the reduced-dose subgroup had lower all-cause (5.3% vs. 10.6%, p = 0.02) and cardiac-related mortality (1.9% vs. 5.1%, p = 0.04), whereas the younger patients receiving reduced-dose rivaroxaban had higher all-cause mortality (3.7% vs. 1.8%, p = 0.01) but no difference in cardiac-related mortality (1.2% vs. 0.7%, p = 0.33). The rate of hospitalization for heart failure was significantly lower in the elderly group with reduced-dose rivaroxaban (7.2% vs. 15.7%, p < 0.01) but not in the younger group. After adjusting for confounders in the older group, treatment with reduced-dose rivaroxaban was associated with lower risk of all-cause mortality (adjusted HR (aHR): 0.40, 95% CI: 0.21-0.74, p < 0.01) and hospitalization for heart failure (aHR: 0.54, 95% CI: 0.29-0.99, p = 0.05). No associations were found between rivaroxaban dose and cardiac-related mortality in either group, nor between younger age and any outcome.

CONCLUSIONS

Reduced-dose rivaroxaban was associated with lower risks of all-cause mortality and hospitalization for heart failure in older patients with nonvalvular atrial fibrillation. Future studies can investigate the effect of reduced-dose rivaroxaban on prognoses in elderly individuals ≥85 years in the west.

Efficacy and safety of direct oral anticoagulants in older adults with atrial fibrillation: a prospective single-centre cohort study

INTRODUCTION

Direct oral anticoagulants (DOACs) are underused in the elderly, regardless the evidence in their favour in this population.

METHODS

We prospectively enrolled anticoagulant-naïve patients aged ≥ 75 years who started treatment with DOACs for atrial fibrillation (AF) and stratified them in older adults (aged 75-84 years) and extremely older adults (≥ 85 years). Thrombotic and hemorrhagic events were evaluated for 12 months follow-up.

RESULTS

We enrolled 518 consecutive patients. They were mostly aged 75-84 years (299 patients; 57.7%) vs. ≥ 85 years (219 patients; 42.3%). Extremely older adults showed higher incidence of all the endpoints (systemic cardioembolism [HR 3.25 (95% CI 1.71-6.18)], major bleeding [HR 2.75 (95% CI 1.77-4.27)], and clinically relevant non-major bleeding [HR 2.13 (95% CI 1.17-3.92)]) vs. older adults during the first year after starting anticoagulation. In patients aged ≥ 85 years, no difference in the aforementioned endpoints was found between those receiving on-label vs. off-label DOACs. In the extremely older adults, chronic kidney disease, polypharmacy, use of antipsychotics, and DOAC discontinuation correlated with higher rates of thrombotic events, whereas a history of bleeding, Charlson Index ≥ 6, use of reduced DOAC dose, absence of a caregiver, use of non-steroidal anti-inflammatory drugs (NSAIDs), and HAS-BLED score ≥ 3 were associated with major bleedings.

CONCLUSIONS

Naïve patients aged ≥ 85 who started a DOAC for AF are at higher risk of thrombotic and bleeding events compared to those aged 75-84 years in the first year of therapy. History of bleeding, HAS-BLED score ≥ 3 and use of NSAIDs are associated with higher rates of major bleeding.

Development and Validation of the DOAC Score: A Novel Bleeding Risk Prediction Tool for Patients With Atrial Fibrillation on Direct-Acting Oral Anticoagulants

BACKGROUND

Current clinical decision tools for assessing bleeding risk in individuals with atrial fibrillation (AF) have limited performance and were developed for individuals treated with warfarin. This study develops and validates a clinical risk score to personalize estimates of bleeding risk for individuals with atrial fibrillation taking direct-acting oral anticoagulants (DOACs).

METHODS

Among individuals taking dabigatran 150 mg twice per day from 44 countries and 951 centers in this secondary analysis of the RE-LY trial (Randomized Evaluation of Long-Term Anticoagulation Therapy), a risk score was developed to determine the comparative risk for bleeding on the basis of covariates derived in a Cox proportional hazards model. The risk prediction model was internally validated with bootstrapping. The model was then further developed in the GARFIELD-AF registry (Global Anticoagulant Registry in the Field-Atrial Fibrillation), with individuals taking dabigatran, edoxaban, rivaroxaban, and apixaban. To determine generalizability in external cohorts and among individuals on different DOACs, the risk prediction model was validated in the COMBINE-AF (A Collaboration Between Multiple Institutions to Better Investigate Non-Vitamin K Antagonist Oral Anticoagulant Use in Atrial Fibrillation) pooled clinical trial cohort and the Quebec Régie de l'Assurance Maladie du Québec and Med-Echo Administrative Databases (RAMQ) administrative database. The primary outcome was major bleeding. The risk score, termed the DOAC Score, was compared with the HAS-BLED score.

RESULTS

Of the 5684 patients in RE-LY, 386 (6.8%) experienced a major bleeding event, within a median follow-up of 1.74 years. The prediction model had an optimism-corrected C statistic of 0.73 after internal validation with bootstrapping and was well-calibrated based on visual inspection of calibration plots (goodness-of-fit P=0.57). The DOAC Score assigned points for age, creatinine clearance/glomerular filtration rate, underweight status, stroke/transient ischemic attack/embolism history, diabetes, hypertension, antiplatelet use, nonsteroidal anti-inflammatory use, liver disease, and bleeding history, with each additional point scored associated with a 48.7% (95% CI, 38.9%-59.3%; P<0.001) increase in major bleeding in RE-LY. The score had superior performance to the HAS-BLED score in RE-LY (C statistic, 0.73 versus 0.60; P for difference <0.001) and among 12 296 individuals in GARFIELD-AF (C statistic, 0.71 versus 0.66; P for difference = 0.025). The DOAC Score had stronger predictive performance than the HAS-BLED score in both validation cohorts, including 25 586 individuals in COMBINE-AF (C statistic, 0.67 versus 0.63; P for difference <0.001) and 11 945 individuals in RAMQ (C statistic, 0.65 versus 0.58; P for difference <0.001).

CONCLUSIONS

In individuals with atrial fibrillation potentially eligible for DOAC therapy, the DOAC Score can help stratify patients on the basis of expected bleeding risk.

Stroke-Specific Predictors of Major Bleeding in Anticoagulated Patients With Stroke and Atrial Fibrillation: A Nationwide Multicenter Registry-Based Study

BACKGROUND AND PURPOSE

The congestive heart failure, hypertension, age, diabetes, previous stroke/transient ischemic attack (CHA2DS2-VASc) and hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile international normalized ratio, elderly, drugs/alcohol (HAS-BLED) scores have been validated in estimating the risks of ischemic stroke and major bleeding, respectively, in patients with atrial fibrillation (AF). This study investigated stroke-specific predictors of major bleeding in patients with stroke and AF who were taking oral anticoagulants (OACs).

METHODS

Subjects were selected from patients enrolled in the Korean ATrial fibrillaTion EvaluatioN regisTry in Ischemic strOke patieNts (K-ATTENTION) nationwide multicenter registry between 2013 and 2015. Patients were excluded if they were not taking OACs, had no brain imaging data, or had intracranial bleeding directly related to the index stroke. Major bleeding was defined according to International Society of Thrombosis and Haemostasis criteria. Cox regression analyses were performed to assess the associations between clinical variables and major bleeding and Kaplan-Meier estimates were performed to analyze event-free survival.

RESULTS

Of a total of 3,213 patients, 1,414 subjects (mean age of 72.6 years, 52.5% males) were enrolled in this study. Major bleeding was reported in 34 patients during the median follow-up period of 1.73 years. Multivariable analysis demonstrated that initial National Institutes of Health Stroke Scale scores (hazard ratio [HR] 1.07, p=0.006), hypertension (HR 3.18, p=0.030), persistent AF type (HR 2.51, p=0.016), and initial hemoglobin level (HR 0.74, p=0.001) were independently associated with major bleeding risk. Except for hypertension, these associations remained significant after adjusting for the HAS-BLED score. Intracranial atherosclerosis presented a trend of association without statistical significance (HR 2.21, p=0.050).

CONCLUSIONS

This study found that major bleeding risk was independently associated with stroke-specific factors in anticoagulated patients with stroke and AF. This has the clinical implication that baseline characteristics of patients with stroke and AF should be considered in secondary prevention, which would bring the net clinical benefit of balancing recurrent stroke prevention with minimal bleeding complications.

A network meta-analysis of the antithrombotic strategies in patients with atrial fibrillation and percutaneous coronary interventions: Focus on bleeding

BACKGROUND

We performed a network meta-analysis of randomized controlled trials comparing non-vitamin K antagonist oral anticoagulant (NOAC)-based versus vitamin K antagonists (VKA)-based regimens in patients with atrial fibrillation (AF) and acute coronary syndromes or PCI, aiming to examine the precise impact of recently established antithrombotic strategies on major bleeding as primary end-point and other safety and efficacy as secondary end-points.

METHODS

A literature search was conducted for randomized controlled trials. Our search took place in three major databases. The primary endpoint of our study was bleeding. To combine direct and indirect evidence across trials, a frequentist network meta-analysis with a random-effects model was used.

RESULTS

Five studies were found eligible for the meta-analysis enrolling a total of 11,542 patients. Five studies (N = 4903 patients) contributed to the network. Compared to the triple antithrombotic therapy (TAT)-based VKA, only the dual antithrombotic therapy (DAT) based NOAC reduced the bleeding (RR 0.57, 95%CI 0.40-0.82). There was no statistically significant difference between DAT-based VKA (RR = 0.66, 95%CI = 0.40-1.09) or TAT-based NOAC (RR = 0.80, 95%CI = 0.43-1.49). DAT-based NOAC ranked best (P-score = 0.91), followed by DAT-based VKA (P-score = 0.67), TAT-based NOAC (P-score = 0.40), and TAT-based VKA (P-score = 0.03).

CONCLUSION

The network meta-analysis of four antithrombotic strategies, demonstrated that in patients with AF undergoing PCI the combination of DAT-based NOAC is associated with a significantly lower risk of major bleeding events. This strategy does not seem to be less effective in terms of prevention of ischemic events compared to the other regimens.

Use of the CHA2DS2-VASc score to predict subsequent myocardial infarction in atrial fibrillation

BACKGROUND

The risk of subsequent myocardial infarction (MI) varies widely in patients with atrial fibrillation (AF). No convenient scoring system currently exists to identify MI in AF. While each element of the CHA2DS2-VASc (congestive heart failure; hypertension; age ≥75 years [doubled]; type 2 diabetes; previous stroke or thromboembolism [doubled]; vascular disease; age 65-75 years; and sex category) score can increase the likelihood of MI, this retrospective longitudinal study aimed to determine the accuracy of the CHA2DS2-VASc score in predicting subsequent MI risk in AF.

METHODS

A total of 29,341 patients with AF were enrolled and followed up from January 2010 until the first occurrence of MI or until December 2020. The primary endpoint was the occurrence of subsequent MI.

RESULTS

The average age of the study population was 71 years, and 43.2% were male. The mean CHA2DS2-VASc score was found to be higher in patients with AF who had experienced an MI than in those who had not (3.56 ± 1.92 vs. 3.32 ± 1.81, p < 0.001). During the long-term follow-up, the risk of subsequent MI increased by 22% with every one-point increase in the CHA2DS2-VASc score (hazard ratio 1.22, 95% confidence interval 1.19-1.25; p < 0.001). Kaplan-Meier analysis revealed that high CHA2DS2-VASc scores were more likely to experience an MI than those with low CHA2DS2-VASc scores (log-rank p < 0.001). Furthermore, the CHA2DS2-VASc score was a significant predictor of MI in multivariate regression analysis.

CONCLUSION

The CHA2DS2-VASc score is a valuable predictor of subsequent MI risk in patients with AF.

Atrial fibrillation and stroke prevention: 25 years of research at EP Europace journal

Stroke prevention in patients with atrial fibrillation (AF) is one pillar of the management of this common arrhythmia. Substantial advances in the epidemiology and associated pathophysiology underlying AF-related stroke and thrombo-embolism are evident. Furthermore, the introduction of the non-vitamin K antagonist oral anticoagulants (also called direct oral anticoagulants) has clearly changed our approach to stroke prevention in AF, such that the default should be to offer oral anticoagulation for stroke prevention, unless the patient is at low risk. A strategy of early rhythm control is also beneficial in reducing strokes in selected patients with recent onset AF, when compared to rate control. Cardiovascular risk factor management, with optimization of comorbidities and attention to lifestyle factors, and the patient's psychological morbidity are also essential. Finally, in selected patients with absolute contraindications to long-term oral anticoagulation, left atrial appendage occlusion or exclusion may be considered. The aim of this state-of-the-art review article is to provide an overview of the current status of AF-related stroke and prevention strategies. A holistic or integrated care approach to AF management is recommended to minimize the risk of stroke in patients with AF, based on the evidence-based Atrial fibrillation Better Care (ABC) pathway, as follows: A: Avoid stroke with Anticoagulation; B: Better patient-centred, symptom-directed decisions on rate or rhythm control; C: Cardiovascular risk factor and comorbidity optimization, including lifestyle changes.

Antithrombotic Treatment in Patients With Hemophilia: an EHA-ISTH-EAHAD-ESO Clinical Practice Guidance

Cardiovascular disease is an emerging medical issue in patients with hemophilia (PWH) and its prevalence is increasing up to 15% in PWH in the United States. Atrial fibrillation, acute and chronic coronary syndromes, venous thromboembolism, and cerebral thrombosis are frequent thrombotic or prothrombotic situations, which require a careful approach to fine-tune the delicate balance between thrombosis and hemostasis in PWH when using both procoagulant and anticoagulant treatments. Generally, PWH could be considered as being naturally anticoagulated when clotting factors are <20 IU/dL, but specific recommendations in patients with very low levels according to the different clinical situations are lacking and mainly based on the anecdotal series. For PWH with baseline clotting factor levels >20 IU/dL in need for any form of antithrombotic therapy, usually treatment without additional clotting factor prophylaxis could be used, but careful monitoring for bleeding is recommended. For antiplatelet treatment, this threshold could be lower with single-antiplatelet agent, but again factor level should be at least 20 IU/dL for dual antiplatelet treatment. In this complex growing scenario, the European Hematology Association in collaboration with the International Society on Thrombosis and Haemostasis, the European Association for Hemophilia and Allied Disorders, the European Stroke Organization, and a representative of the European Society of Cardiology Working Group on Thrombosis has produced this current guidance document to provide clinical practice recommendations for health care providers who care for PWH.

Management of Gastrointestinal Bleeding and Resumption of Oral Anticoagulant Therapy in Patients with Atrial Fibrillation: A Multidisciplinary Discussion

Direct oral anticoagulants (DOACs) are recommended for the prevention of thromboembolism in patients with atrial fibrillation (AF), and are now preferred over vitamin K antagonists due to their beneficial efficacy and safety profile. However, all oral anticoagulants carry a risk of gastrointestinal (GI) bleeding. Although the risk is well documented and acute bleeding well codified, there is limited high-quality evidence and no guidelines to guide physicians on the optimal management of anticoagulation after a GI bleeding event. The aim of this review is to provide a multidisciplinary critical discussion of the optimal management of GI bleeding in patients with AF receiving oral anticoagulants to help physicians provide individualized treatment for each patient and optimize outcomes. It is important to perform endoscopy when a patient presents with bleeding manifestations or hemodynamic instability to determine the bleed location and severity of bleeding and then perform initial resuscitation. Administration of all anticoagulants and antiplatelets should be stopped and bleeding allowed to resolve with time; however, anticoagulant reversal should be considered for patients who have life-threatening bleeding or when the bleeding is not controlled by the initial resuscitation. Anticoagulation needs to be timely resumed considering that bleeding risk outweighs thrombotic risk when anticoagulation is resumed early after the bleeding event. To prevent further bleeding, physicians should prescribe anticoagulant therapy with the lowest risk of GI bleeding, avoid medications with GI toxicity, and consider the effect of concomitant medications on potentiating the bleeding risk.

A Cost-Effectiveness Analysis of Biomarkers for Risk Prediction in Atrial Fibrillation

RATIONALE

Atrial fibrillation (AF) is associated with an increased risk of thromboembolism. This risk is currently assessed with scoring systems based on clinical characteristics. However, these tools have limited prognostic performance. Circulating biomarkers are proposed for improved prediction of major clinical events and individualization of treatments in patients with AF.

OBJECTIVE

The aim was to assess the cost-effectiveness of precision medicine (PM), i.e., the use of combined biomarkers and clinical variables, in comparison to standard of care (SOC) for risk stratification in a hypothetical cohort of AF patients at risk of stroke.

METHODS

A Markov cohort model was developed to evaluate the costs and quality-adjusted life-years (QALYs) of PM compared to SOC, over 20 years using a Canadian healthcare system perspective.

RESULTS

PM decreased the mean per-patient overall costs by 7% ($94,932 vs $102,057 [Canadian dollars], respectively) and increased the QALYs by 12% (8.77 vs 7.68 QALYs, respectively). The calculated incremental cost-effectiveness ratio was negative, indicating that PM is an economically dominant strategy. These results were robust to one-way and probabilistic sensitivity analyses.

CONCLUSION

PM compared to SOC is economically dominant and is projected to generate cost savings.

HAS-BLED vs. ORBIT scores in anticoagulated patients with atrial fibrillation: A systematic review and meta-analysis

Background

The 2021 UK National Institute for Health and Care Excellence guidelines tend to recommend the ORBIT score for predicting bleeding risk in patients with atrial fibrillation (AF) with anticoagulants. Herein, we comprehensively re-assessed the predicted abilities of the HAS-BLED vs. ORBIT score since several newly published data showed different findings.

Methods

We comprehensively searched the PubMed electronic database until December 2021 to identify relevant studies reporting the ORBIT vs. HAS-BLED scores in anticoagulated patients with AF. Their predicted abilities were assessed using the C-index, reclassification, and calibration analysis.

Results

Finally, 17 studies were included in this review. In the pooled analysis, the ORBIT score had a C-index of 0.63 (0.60-0.66), 0.59 (0.53-0.66), and 0.57 (0.48-0.67) for major bleeding, any clinically relevant bleeding, and intracranial bleeding, respectively, while the HAS-BLED score had a C-index of 0.61 (0.59-0.63), 0.59 (0.56-0.63), and 0.57 (0.51-0.64) for major bleeding, any clinically relevant bleeding, and intracranial bleeding, respectively. There were no statistical differences in the accuracy of predicting these bleeding events between the two scoring systems. For the outcome of major bleeding, the subgroup analyses based on vitamin K antagonists vs. direct oral anticoagulants suggested no differences in the discrimination ability between the HAS-BLED and ORBIT scores. Reclassification and calibration analyses of HAS-BLED vs. ORBIT should be further assessed due to the limited and conflicting data.

Conclusion

Our current findings suggested that the HAS-BLED and ORBIT scores at least had similar predictive abilities for major bleeding risk in anticoagulated (vitamin K antagonists or direct oral anticoagulants) patients with AF, supporting the use of the HAS-BLED score in clinical practice.

Essen Stroke Risk Score Predicts Clinical Outcomes in Heart Failure Patients with Preserved Ejection Fraction: Evidence from the TOPCAT trial

BACKGROUND

 Heart failure (HF) with preserved ejection fraction (HFpEF) is associated with increased risks of stroke and other adverse outcomes.

AIMS

 This study sought to determine whether the Essen Stroke Risk Score (ESRS) could predict the risks of adjudicated clinical outcomes in patients with HFpEF from the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial.

METHODS

 We evaluated associations of baseline ESRS with clinical outcomes by using the Cox proportional hazard model with competing risk regression. The diagnostic accuracy of the ESRS was assessed using the C-index and calibration data.

RESULTS

 Of 3,441 HFpEF patients with a mean follow-up of 3.3 years, the risk of stroke ranged from 0.32% per year at an ESRS of 1 to 2 points to 1.71% per year at a score of ≥6 points. Each point increase in ESRS was associated with increased risks of primary composite outcome (hazard ratios [HRs] = 1.31; 95% confidence intervals [CIs]: 1.23-1.40; C-index = 0.68), stroke (HR = 1.33 [95% CI: 1.16-1.53]; C-index = 0.68), myocardial infarction (HR = 1.60 [95% CI: 1.40-1.83]; C-index = 0.75), HF hospitalization (HR = 1.30 [95% CI: 1.20-1.41]; C-index = 0.71), any hospitalization (HR = 1.20, 95% CI: 1.15-1.26; C-index = 0.68), cardiovascular death (HR = 1.32 [95% CI: 1.20-1.44]; C-index = 0.68), and all-cause death (HR = 1.37, [95% CI: 1.28-1.48]; C-index = 0.68). The calibration curves showed that the ESRS had a better agreement between predicted and observed stroke risks compared with the R2CHADS2, CHADS2, or CHA2DS2-VASC stroke scores.

CONCLUSION

 The ESRS had modest discriminatory abilities for predicting stroke as well as other adverse outcomes including myocardial infarction, hospitalization, and death in HFpEF patients. ESRS might have better calibration performance than R2CHADS2, CHADS2, or CHA2DS2-VASC in HFpEF at high risk for stroke.

CLINICAL TRIAL REGISTRATION

 URL: https://clinicaltrials.gov. Unique identifier: NCT00094302.

Predicting performance of the HAS-BLED and ORBIT bleeding risk scores in patients with atrial fibrillation treated with Rivaroxaban: Observations from the prospective EMIR Registry

BACKGROUND

Assessing bleeding risk during the decision-making process of starting oral anticoagulation (OAC) therapy in atrial fibrillation (AF) patients is essential. Several bleeding risk scores have been proposed for vitamin K antagonist users but, few studies have focused on validation of these bleeding risk scores in patients taking direct oral anticoagulants (DOACs). The aim was to compare the predictive ability of HAS-BLED and ORBIT bleeding risk scores in AF patients taking rivaroxaban in the EMIR ('Estudio observacional para la identificación de los factores de riesgo asociados a eventos cardiovasculares mayores en pacientes con fibrilación auricular no valvular tratados con un anticoagulante oral directo [Rivaroxaban]) Study.

METHODS AND RESULTS

EMIR Study was an observational, multicenter, post-authorization, and prospective study that involved AF patients under OAC with rivaroxaban at least 6 months before enrolment. We analysed baseline clinical characteristics and adverse events after 2.5 years of follow-up and validated the predictive ability of HAS-BLED and ORBIT scores for major bleeding (MB) events.We analysed 1433 patients with mean age of 74.2 ± 9.7 (44.5% female). Mean HAS-BLED score was 1.6 ± 1.0 and ORBIT score was 1.1 ± 1.2. The ORBIT score categorised a higher proportion of patients as 'low-risk' (87.1%) compared with 53.5% using the HAS-BLED score. There were 33 MB events (1.04%/year) and 87 patients died (2.73%/year). Both HAS-BLED and ORBIT had a good predictive ability for MB{Area under the curve (AUC) 0.770, [95% confidence interval (CI) 0.693-0.847; P <0.001] and AUC 0.765 (95% CI 0.672-0.858; P <0.001), respectively}. There was a non-significant difference for discriminative ability of the two tested scores (P = 0.930) and risk reclassification in terms of net reclassification improvement (NRI) -5.7 (95% CI -42.4-31.1; P = 0.762). HAS-BLED score showed the best calibration and ORBIT score showed the largest mismatch in calibration, particularly in higher predicted risk patients.

CONCLUSION

In a prospective real-world AF population under rivaroxaban from EMIR registry, the HAS-BLED score had good predictive performance and calibration compared with ORBIT score for MB events. ORBIT score presented worse calibration than HAS-BLED in this DOAC treated population.

Performance of the HAS-BLED, ORBIT, and ATRIA Bleeding Risk Scores on a Cohort of 399 344 Hospitalized Patients With Atrial Fibrillation and Cancer: Data From the French National Hospital Discharge Database

Background The association between cancer types and specific bleeding events in patients with atrial fibrillation has been scarcely investigated. Also, the performance of bleeding risk scores in this high-risk subgroup of patients is unclear. We investigated the rate of any bleeding, intracranial hemorrhage, major bleeding, and gastrointestinal bleeding according to cancer types in patients with atrial fibrillation. We also tested the predictive value of HAS-BLED, ATRIA, and ORBIT bleeding risk scores. Methods and Results Observational retrospective cohort study including hospitalized patients with atrial fibrillation and cancer from the French National Hospital Discharge Database (Programme de Medicalisation des Systemes d'Information) from January 2010 to December 2019. Major bleeding was defined according to Bleeding Academic Research Consortium definitions. Patients with HAS-BLED ≥3, ATRIA ≥5, or ORBIT ≥4 were classified as at high bleeding risk. Receiver operating characteristic analysis for each score against any bleeding, major bleeding, gastrointestinal bleeding, and intracranial hemorrhage was performed. Areas under the curve (AUCs) were then compared. We included 399 344 patients. Mean age was 77.9±10.2 years, and 63.2% were men. The highest intracranial hemorrhage rates were found in leukemia (1.89%/year), myeloma (1.52%/year), lymphoma and liver (1.45%/year), and pancreas cancer (1.41%/year). Receiver operating characteristic analysis showed that ORBIT score predicted best for any bleeding. In addition, ORBIT score ≥4 had the highest predictivity for major bleeding (AUC, 0.805), followed by HAS-BLED ≥3 and ATRIA ≥5 (AUCs, 0.716 and 0.700, respectively). HAS-BLED and ORBIT performed best for intracranial hemorrhage (AUCs, 0.744 and 0.742 for continuous scores, respectively), better than ATRIA (AUC, 0.635). For gastrointestinal bleeding, ORBIT ≥4 had the highest predictivity (AUC, 0.756), followed by the HAS-BLED ≥3 (AUC, 0.702) and ATRIA ≥5 (AUC, 0.662). Conclusions Some cancer types carry a greater bleeding risk in patients with atrial fibrillation. The identification and management of modifiable bleeding risk factors is crucial in these patients, as well as to flag up high bleeding risk patients for early review and follow-up.

Incidence and Determinants of Spontaneous Cardioversion of Early Onset Symptomatic Atrial Fibrillation

Atrial fibrillation (AF) is the most frequent chronic arrhythmia worldwide, and it is associated with significant morbidity and mortality, making it a considerable burden both to patients and the healthcare system. Nowadays, an early attempt to restore sinus rhythm in acute symptomatic AF through electrical or pharmacological cardioversion is the most common approach in the Emergency Department (ED). However, considering the high percentage of spontaneous cardioversion of paroxysmal AF reported by many studies, this approach may not be the ideal choice for all patients. In this manuscript we performed a review of the most relevant studies found in literature with the aim of identifying the main determinants of spontaneous cardioversion, focusing on those easy to detect in the ED. We have found that the most relevant predictors of spontaneous cardioversion are the absence of Heart Failure (HF), a small atrial size, recent-onset AF, rapid Atrial Fibrillatory Rate and the relationship between a previous AF episode and Heart Rate/Blood Pressure. A number of those are utilized, along with other easily determined parameters, in the recently developed "ReSinus" score which predicts the likelihood of AF spontaneous cardioversion. Such identification may help the physician decide whether immediate cardioversion is necessary, or whether to adopt a "watch-and-wait" strategy in the presence of spontaneous cardioversion determinants.

Rule-based definition of muscle bundles in patient-specific models of the left atrium

Atrial fibrillation (AF) is the most common arrhythmia encountered clinically, and as the population ages, its prevalence is increasing. Although the CHA2DS2−VASc score is the most used risk-stratification system for stroke risk in AF, it lacks personalization. Patient-specific computer models of the atria can facilitate personalized risk assessment and treatment planning. However, a challenge faced in creating such models is the complexity of the atrial muscle arrangement and its influence on the atrial fiber architecture. This work proposes a semi-automated rule-based algorithm to generate the local fiber orientation in the left atrium (LA). We use the solutions of several harmonic equations to decompose the LA anatomy into subregions. Solution gradients define a two-layer fiber field in each subregion. The robustness of our approach is demonstrated by recreating the fiber orientation on nine models of the LA obtained from AF patients who underwent WATCHMAN device implantation. This cohort of patients encompasses a variety of morphology variants of the left atrium, both in terms of the left atrial appendages (LAAs) and the number of pulmonary veins (PVs). We test the fiber construction algorithm by performing electrophysiology (EP) simulations. Furthermore, this study is the first to compare its results with other rule-based algorithms for the LA fiber architecture definition available in the literature. This analysis suggests that a multi-layer fiber architecture is important to capture complex electrical activation patterns. A notable advantage of our approach is the ability to reconstruct the main LA fiber bundles in a variety of morphologies while solving for a small number of harmonic fields, leading to a comparatively straightforward and reproducible approach.

N-terminal pro-B-type natriuretic peptide and D-dimer combined with left atrial diameter to predict the risk of ischemic stroke in nonvalvular atrial fibrillation

OBJECTIVES

We aimed to explore the potential role of N-terminal pro-B-type natriuretic peptide (NT-proBNP), d-dimer, and the echocardiographic parameter left atrial diameter (LAD) in identifying and predicting the occurrence of ischemic stroke (IS) in patients with nonvalvular atrial fibrillation (NVAF).

METHODS

We conducted a retrospective study of 445 patients with NVAF in the First Affiliated Hospital of Nanchang University. They were divided into the NVAF (309 cases) and NVAF with stroke (136 cases) groups according to whether acute ischemic stroke (AIS) occurred at admission. Multivariate logistic regression was used to analyze the odds ratio (OR) of NT-proBNP, d-dimer, and LAD for IS. The predictive value of NT-proBNP, d-dimer, and LAD in identifying the occurrence of IS in NVAF was determined by plotting the receiver operating characteristic (ROC) curves.

RESULTS

NT-proBNP, d-dimer, and LAD levels were significantly higher in the NVAF with stroke group than in the NVAF group (p < .05). NT-ProBNP, d-dimer, and LAD were independently associated with IS in NVAF patients (odds ratio [OR] = 1.12, 95% confidence interval [CI]: 1.08-1.16; OR = 1.87, 95% CI: 1.37-2.55; OR = 1.21, 95% CI: 1.13-1.28, p < .01). The optimal cutoff points for NT-ProBNP, d-dimer, and LAD levels to distinguish the NVAF group from the NVAF with stroke group were 715.0 pg/ml, 0.515 ng/ml, and 38.5 mm, respectively, with the area under the curve (AUC) being [0.801 (95% CI: 0.76-0.84); 0.770 (95% CI: 0.72-0.85); 0.752 (95% CI: 0.71-0.80), p < .01]. The combined score of NT-proBNP, d-dimer, and LAD improved the predictive efficacy of the single index, with an AUC of 0.846 (95% CI: 0.81-0.88, p < .01), sensitivity of 77.2%, and specificity of 76.4%.

CONCLUSION

NT-proBNP, d-dimer, and the echocardiographic parameter LAD have outstanding value in predicting the risk of IS in patients with NVAF.

Development of a Care Pathway for Atrial Fibrillation Patients in the Emergency Department

Atrial fibrillation (AF) is the most common cardiac arrhythmia and its prevalence is continuously increasing in the United States, leading to a progressive rise in the number of disease-related emergency department (ED) visits and hospitalizations. Although optimal long-term outpatient management for AF is well defined, the guidelines for optimal ED management of acute AF episodes is less clear. Studies have demonstrated that discharging patients with AF from the ED after acute stabilization is both safe and cost effective; however, the majority of these patients in the United States and in our institution are admitted to the hospital. To improve care of these patients, we established a multidisciplinary collaboration to develop an evidence-based systematic approach for the treatment and management of AF in the ED, that led to the creation of the University of California-Cardioversion, Anticoagulation, Rate Control, Expedited Follow-up/Education Atrial Fibrillation Pathway. Our pathway focuses on the acute stabilization of AF, adherence to best practices for anticoagulation, and reduction in unnecessary admissions through discharge from the ED with expedited outpatient follow-up whenever safe. A novel aspect of our pathway is that it is primarily driven by the ED physicians, while other published protocols primarily involve consulting cardiologists to guide management in the ED. Our protocol is very pertinent considering the current trend toward increased AF prevalence in the United States, coupled with a need for widespread implementation of strategies aimed at improving management of these patients while safely reducing hospital admissions and the economic burden of AF.

Bleeding Risk Assessment in End-Stage Kidney Disease: Validation of Existing Risk Scores and Evaluation of a Machine Learning-Based Approach

BACKGROUND

 Patients with end-stage kidney disease (ESKD) on hemodialysis (HD) are at increased risk for bleeding. However, despite relevant clinical implications regarding dialysis modalities or anticoagulation, no bleeding risk assessment strategy has been established in this challenging population.

METHODS

 Analyses on bleeding risk assessment models were performed in the population-based Vienna InVestigation of Atrial fibrillation and thromboemboLism in patients on hemoDialysIs (VIVALDI) study including 625 patients. In this cohort study, patients were prospectively followed for a median observation period of 3.5 years for the occurrence of major bleeding. First, performances of existing bleeding risk scores (i.e., HAS-BLED, HEMORR2HAGES, ATRIA, and four others) were evaluated in terms of discrimination and calibration. Second, four machine learning-based prediction models that included clinical, dialysis-specific, and laboratory parameters were developed and tested using Monte Carlo cross-validation.

RESULTS

 Of 625 patients (median age: 66 years, 37% women), 89 (14.2%) developed major bleeding, with a 1-year, 2-year, and 3-year cumulative incidence of 6.1% (95% confidence interval [CI]: 4.2-8.0), 10.3% (95% CI: 8.0-12.8), and 13.5% (95% CI: 10.8-16.2), respectively. C-statistics of the seven contemporary bleeding risk scores ranged between 0.54 and 0.59 indicating poor discriminatory performance. The HAS-BLED score showed the highest C-statistic of 0.59 (95% CI: 0.53-0.66). Similarly, all four machine learning-based predictions models performed poorly in internal validation (C-statistics ranging from 0.49 to 0.55).

CONCLUSION

 Existing bleeding risk scores and a machine learning approach including common clinical parameters fail to assist in bleeding risk prediction of patients on HD. Therefore, new approaches, including novel biomarkers, to improve bleeding risk prediction in patients on HD are needed.

Should oral anticoagulants still be prescribed to patients with atrial fibrillation with a single stroke risk factor but at high bleeding risk? A nationwide cohort study

AIMS

To investigate the co-distributions of stroke and bleeding risks in Asian patients with atrial fibrillation (AF) and the clinical benefits of oral anticoagulants (OACs) among AF patients with a single stroke risk factor but at high bleeding risk.

METHODS AND RESULTS

From 1 January 2001 to 31 December 2016, a total of 404 949 AF patients were retrospectively identified from Taiwan National Health Insurance Research Database. Stroke risk was assessed using the CHA2DS2-VASc score and was categorized into low risk (score = 0 for males and 1 for females), intermediate risk (i.e. a single non-sex stroke risk factor; score = 1 for males and 2 for females), and high risk (score ≥2 for males and ≥3 for females). A high risk of bleeding was defined as a HAS-BLED score ≥3. Around 57.5% of AF patients were at high risk for both stroke and bleeding, and most patients (97.6%) with a low stroke risk were also at low risk for bleeding. Around 18.3% of patients with a CHA2DS2-VASc score of 1 (males) or 2 (females) were at high bleeding risk, and the use of OACs in such patients was associated with a lower risk of composite adverse events of ischaemic stroke, intracranial haemorrhage, or mortality (4.19/100 person-years vs. 5.22/100 person-years, adjusted hazard ratio = 0.781, P = 0.04).

CONCLUSION

For AF patients with an intermediate risk of stroke (i.e. a single non-sex stroke risk factor) but at high bleeding risk, the use of OACs was still significantly associated with a better overall clinical outcome.

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

Comprehensive comparison of stroke risk score performance: a systematic review and meta-analysis among 6 267 728 patients with atrial fibrillation

AIMS

Multiple risk scores to predict ischaemic stroke (IS) in patients with atrial fibrillation (AF) have been developed. This study aims to systematically review these scores, their validations and updates, assess their methodological quality, and calculate pooled estimates of the predictive performance.

METHODS AND RESULTS

We searched PubMed and Web of Science for studies developing, validating, or updating risk scores for IS in AF patients. Methodological quality was assessed using the Prediction model Risk Of Bias ASsessment Tool (PROBAST). To assess discrimination, pooled c-statistics were calculated using random-effects meta-analysis. We identified 19 scores, which were validated and updated once or more in 70 and 40 studies, respectively, including 329 validations and 76 updates-nearly all on the CHA2DS2-VASc and CHADS2. Pooled c-statistics were calculated among 6 267 728 patients and 359 373 events of IS. For the CHA2DS2-VASc and CHADS2, pooled c-statistics were 0.644 [95% confidence interval (CI) 0.635-0.653] and 0.658 (0.644-0.672), respectively. Better discriminatory abilities were found in the newer risk scores, with the modified-CHADS2 demonstrating the best discrimination [c-statistic 0.715 (0.674-0.754)]. Updates were found for the CHA2DS2-VASc and CHADS2 only, showing improved discrimination. Calibration was reasonable but available for only 17 studies. The PROBAST indicated a risk of methodological bias in all studies.

CONCLUSION

Nineteen risk scores and 76 updates are available to predict IS in patients with AF. The guideline-endorsed CHA2DS2-VASc shows inferior discriminative abilities compared with newer scores. Additional external validations and data on calibration are required before considering the newer scores in clinical practice.

CLINICAL TRIAL REGISTRATION

ID CRD4202161247 (PROSPERO).

Comparative analysis of left atrial appendage closure efficacy and outcomes by CHA2DS2-VASc score group in patients with non-valvular atrial fibrillation

Background

Higher CHA₂DS₂-VASc score is associated with an increased risk of adverse cardio-cerebrovascular events in patients with non-valvular atrial fibrillation (NVAF), regardless of oral anticoagulation (OAC) status. However, whether this association still exists in patients undergoing left atrial appendage closure (LAAC) is unknown. We evaluated the impact of CHA₂DS₂-VASc score on LAAC efficacy and outcomes.

Methods

A total of 401 consecutive patients undergoing LAAC were included and divided into 3 groups based on CHA₂DS₂-VASc score (0–2, 3–4, and ≥5). Baseline characteristics, periprocedural complications, and long-term outcomes were collected and compared across all groups.

Results

There were no significant differences in implantation success, periprocedural complications, and long-term outcomes across all score groups. Kaplan-Meier estimation showed that the cumulative ratio of freedom from all-cause mortality (P = 0.146), cardiovascular mortality (P = 0.519), and non-cardiovascular mortality (P = 0.168) did not differ significantly by CHA₂DS₂-VASc score group. LAAC decreased the risks of thromboembolism and major bleeding, resulting in a relative risk reduction (RRR) of 82.4% (P < 0.001) and 66.7% (P < 0.001) compared with expected risks in the overall cohort, respectively. Subgroup analysis indicated that observed risks of thromboembolism and major bleeding were significantly lower than the expected risks in score 3–4 and score ≥5 groups, respectively. The level of RRR increased with CHA₂DS₂-VASc score (P < 0.001 for trend) for thromboembolism but not for major bleeding (P = 0.2729 for trend).

Conclusion

Patients with higher CHA₂DS₂-VASc score did not experience worse outcomes, which may be partly attributed to more benefits provided by LAAC intervention in such patients compared to those with a low score.

Assessment and Mitigation of Bleeding Risk in Atrial Fibrillation and Venous Thromboembolism: Executive Summary of a European and Asia-Pacific Expert Consensus Paper

While there is a clear clinical benefit of oral anticoagulation in patients with atrial fibrillation (AF) and venous thromboembolism (VTE) in reducing the risks of thromboembolism, major bleeding events (especially intracranial bleeds) may still occur and be devastating. The decision for initiating and continuing anticoagulation is often based on a careful assessment of both thromboembolism and bleeding risk. The more common and validated bleeding risk factors have been used to formulate bleeding risk stratification scores, but thromboembolism and bleeding risk factors often overlap. Also, many factors that increase bleeding risk are transient and modifiable, such as variable international normalized ratio values, surgical procedures, vascular procedures, or drug-drug and food-drug interactions. Bleeding risk is also not a static "one-off" assessment based on baseline factors but is dynamic, being influenced by aging, incident comorbidities, and drug therapies. In this executive summary of a European and Asia-Pacific Expert Consensus Paper, we comprehensively review the published evidence and propose a consensus on bleeding risk assessments in patients with AF and VTE, with a view to summarizing "best practice" when approaching antithrombotic therapy in these patients. We address the epidemiology and size of the problem of bleeding risk in AF and VTE, and review established bleeding risk factors and summarize definitions of bleeding. Patient values and preferences, balancing the risk of bleeding against thromboembolism, are reviewed, and the prognostic implications of bleeding are discussed. We propose consensus statements that may help to define evidence gaps and assist in everyday clinical practice.

Predictors of Adherence to Stroke Prevention in the BALKAN-AF Study: A Machine-Learning Approach

Background Compared with usual care, guideline-adherent stroke prevention strategy, based on the ABC (Atrial fibrillation Better Care) pathway, is associated with better outcomes. Given that stroke prevention is central to atrial fibrillation (AF) management, improved efforts to determining predictors of adherence with ‘A’ (avoid stroke) component of the ABC pathway are needed.

Purpose We tested the hypothesis that more sophisticated methodology using machine learning (ML) algorithms could do this.

Methods In this post-hoc analysis of the BALKAN-AF dataset, ML algorithms and logistic regression were tested. The feature selection process identified a subset of variables that were most relevant for creating the model. Adherence with the ‘A’ criterion of the ABC pathway was defined as the use of oral anticoagulants (OAC) in patients with AF with a CHA2DS2-VASc score of 0 (male) or 1 (female).

Results Among 2,712 enrolled patients, complete data on ‘A’-adherent management were available in 2,671 individuals (mean age 66.0 ± 12.8; 44.5% female). Based on ML algorithms, independent predictors of ‘A-criterion adherent management’ were paroxysmal AF, center in capital city, and first-diagnosed AF. Hypertrophic cardiomyopathy, chronic kidney disease with chronic dialysis, and sleep apnea were independently associated with a lower likelihood of ‘A’-criterion adherent management.

ML evaluated predictors of adherence with the ‘A’ criterion of the ABC pathway derived an area under the receiver-operator curve of 0.710 (95%CI 0.67–0.75) for random forest with fine tuning.

Conclusions Machine learning identified paroxysmal AF, treatment center in the capital city, and first-diagnosed AF as predictors of adherence to the A pathway; and hypertrophic cardiomyopathy, chronic kidney disease with chronic dialysis, and sleep apnea as predictors of non adherence.

Comparing atrial fibrillation guidelines: Focus on stroke prevention, bleeding risk assessment and oral anticoagulant recommendations

Clinical practice in atrial fibrillation (AF) patient management is constantly evolving. In the past 3 years, various new AF guidelines or focused updates have been published, given this rapidly evolving field. In 2019, the American College of Cardiology/American Heart Association published a focused update of the 2014 guidelines. In 2020, both the European Society of Cardiology and the Canadian Cardiovascular Society released their new guidelines. Finally, the most recent guidelines were those published in 2021 by the Asian Pacific Heart Rhythm Society, which updates their 2017 version and the 2021 National Institute for Health and Care Excellence (NICE) guidelines. In the present narrative review, we compare these guidelines, emphasizing similarities and differences in the following mainstay elements of patient care: thromboembolic risk assessment, oral anticoagulants (OACs) prescription, bleeding risk evaluation, and integrated patient management. A formal evaluation of baseline thromboembolic and bleeding risks and their reassessment during follow-up is evenly recommended, although some differences in using risk stratification scores. OACs prescription is highly encouraged where appropriate, and prescription algorithms are broadly similar. The importance of an integrated and multidisciplinary approach to patient care is emerging, aiming to address several different aspects of a multifaceted disease.

Stroke Risk Stratification in Patients With Postoperative Atrial Fibrillation After Coronary Artery Bypass Grafting

Background

The CHA₂DS₂‐VASc (congestive heart failure, hypertension, age ≥75 years, diabetes, previous stroke or TIA [transient ischemic attack], vascular disease, age 65 to 74 years, sex category female; 2 indicates 2 points, otherwise 1 point) scoring system is recommended to guide decisions on oral anticoagulation therapy for stroke prevention in patients with nonsurgery atrial fibrillation. A score ≥1 in men and ≥2 in women, corresponding to an annual stroke risk exceeding 1%, warrants long‐term oral anticoagulation provided the bleeding risk is acceptable. However, in patients with new‐onset postoperative atrial fibrillation, the optimal risk stratification method is unknown. The aim of this study was therefore to evaluate the CHA₂DS₂‐VASc scoring system for estimating the 1‐year ischemic stroke risk in patients with new‐onset postoperative atrial fibrillation after coronary artery bypass grafting.

Methods and Results

All patients with new‐onset postoperative atrial fibrillation and without oral anticoagulation after first‐time isolated coronary artery bypass grafting performed in Sweden during 2007 to 2017 were eligible for this registry‐based observational cohort study. The 1‐year ischemic stroke rate at each step of the CHA₂DS₂‐VASc score was estimated using a Kaplan‐Meier estimator. Of the 6368 patients included (mean age, 69.9 years; 81% men), >97% were treated with antiplatelet drugs. There were 147 ischemic strokes during the first year of follow‐up. The ischemic stroke rate at 1 year was 0.3%, 0.7%, and 1.5% in patients with CHA₂DS₂‐VASc scores of 1, 2, and 3, respectively, and ≥2.3% in patients with a score ≥4. A sensitivity analysis, with the inclusion of patients on anticoagulants, was performed and supported the primary results.

Conclusions

Patients with new‐onset atrial fibrillation after coronary artery bypass grafting and a CHA₂DS₂‐VASc score <3 have such a low 1‐year risk for ischemic stroke that oral anticoagulation therapy should probably be avoided.

Elevated plasma Ninjurin-1 levels in atrial fibrillation is associated with atrial remodeling and thromboembolic risk

BACKGROUND

Nerve injury-induced protein 1 (Ninj1) is elevated in various inflammatory diseases. The soluble form of Ninj1 yield by matrix metalloproteinase cleavage is a secreted protein and inhibits cell adhesion and inflammation. However, the role of plasma Ninj1 in atrial fibrillation (AF) has not been reported. The present study aimed to investigate the correlation between plasma Ninj1 levels and AF.

METHODS

A total of 96 AF patients [age 66.00 (60.00, 72.00) years, male 56 (58.33%)] and 51 controls without AF [age 65.00 (55.00, 68.00) years, male 21 (41.18%)] were enrolled in this study. Plasma Ninj1 concentrations were detected using enzyme-linked immunosorbent assay. Also, the clinical characteristics, left atrial volume index (LAVI), CHA2DS2-VASc score, and HAS-BLED score were evaluated.

RESULTS

Plasma Ninj1 levels were significantly higher in patients with AF than in controls (P < 0.001). Plasma Ninj1 levels were positively correlated with LAVI (P = 0.019) and CHA2DS2-VASc score (P = 0.024). Logistic regression analysis confirmed that the Ninj1 plasma levels were associated with AF (P = 0.009). The receiver operating characteristic analysis showed that plasma Ninj1 had a predictive value for AF (P < 0.001).

CONCLUSIONS

Plasma Ninj1 levels were elevated in patients with AF, associated with left atrial enlargement and thromboembolic risk in AF.

Atrial fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia despite substantial efforts to understand the pathophysiology of the condition and develop improved treatments. Identifying the underlying causative mechanisms of AF in individual patients is difficult and the efficacy of current therapies is suboptimal. Consequently, the incidence of AF is steadily rising and there is a pressing need for novel therapies. Research has revealed that defects in specific molecular pathways underlie AF pathogenesis, resulting in electrical conduction disorders that drive AF. The severity of this so-called electropathology correlates with the stage of AF disease progression and determines the response to AF treatment. Therefore, unravelling the molecular mechanisms underlying electropathology is expected to fuel the development of innovative personalized diagnostic tools and mechanism-based therapies. Moreover, the co-creation of AF studies with patients to implement novel diagnostic tools and therapies is a prerequisite for successful personalized AF management. Currently, various treatment modalities targeting AF-related electropathology, including lifestyle changes, pharmaceutical and nutraceutical therapy, substrate-based ablative therapy, and neuromodulation, are available to maintain sinus rhythm and might offer a novel holistic strategy to treat AF.

Variation in bleeding risk estimates among online calculators: Cross-sectional study of apps used by and for patients with atrial fibrillation

OBJECTIVE

To assess the variation in bleeding risk estimates and risk stratification among Web and mobile applications for patients with atrial fibrillation.

DESIGN

Cross-sectional study.

SETTING

Simulated patient population.

PARTICIPANTS

Hypothetical patient cohorts that encompassed all possible binary risk factor combinations for each clinical prediction model.

INTERVENTIONS

Twenty-five bleeding risk calculators (18 Web and 7 mobile apps), each of which used 1 of 4 clinical prediction models to predict an individual's 12-month bleed risk: ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation), HAS-BLED (hypertension [systolic blood pressure >160 mm Hg], abnormal renal or liver function, stroke [caused by bleeding], bleeding, labile international normalized ratio, elderly [age >65 years], drugs [acetylsalicylic acid or nonsteroidal anti-inflammatory drugs] or alcohol [≥8 drinks per week]), HEMORR₂HAGES (hepatic or renal disease, ethanol abuse, malignancy, older [age >75 years], reduced platelet count or function, rebleeding risk [history of past bleeding], hypertension [uncontrolled], anemia, genetic factors, excessive fall risk, and stroke), and mOBRI (modified Outpatient Bleeding Risk Index).

MAIN OUTCOME MEASURES

Four simulated cohorts were constructed. The coefficient of variation, relative difference (RD), and 95% CI for annual bleeding risk estimates were calculated for all hypothetical patient cohorts. Additionally, pairwise agreement between calculators across low- (<10%), moderate- (10% to 20%), and high-risk (>20%) categories of patients was determined.

RESULTS

The risk estimates the calculators generated were imprecise, with coefficients of variation ranging from 14% for HEMORR₂HAGES to 64% for mOBRI. Wide variation was observed in annual risk estimates for calculators using the mOBRI (maximum RD=4.3) and HAS-BLED (maximum RD=3.1) models. The 95% CI of mean annual bleeding risk varied among models; 1 calculator using the HAS-BLED model had a 95% CI of mean annual risk estimates of 5.4% to 6.2%, while another HAS-BLED calculator reported a 95% CI of 17.7% to 18.5%. Concordance for risk category stratification among calculators was high for those based on mOBRI and ATRIA (=1 for both). Poor agreement was observed in 1 calculator using HEMORR₂HAGES (=0.54) and another using HAS-BLED ( range=-0.11 to 0.35).

CONCLUSION

Inconsistencies and a lack of precision were observed in annual risk estimates and risk stratification produced by Web and mobile bleeding risk calculators for patients with atrial fibrillation. Clinicians should refer to annual bleeding risks observed in major randomized controlled trials to inform risk estimates communicated to patients.

Mitral Regurgitation and Body Mass Index Increase the Predictability of Perioperative Bleeding in Anticoagulated Patients With Nonvalvular Atrial Fibrillation

Background

Catheter ablation (CA) effectively restores sinus rhythm in atrial fibrillation (AF) but causes a short-term fluctuation in the coagulation state. Potential risk factors and better management during this perioperative period remain understudied.

Methods

We consecutively included 940 patients with nonvalvular AF who received CA at Fuwai Hospital, Beijing, China. Patients were divided into two groups according to their bleeding status during 3 months' anticoagulation. Any adverse events related to bleeding in the 3 months were evaluated. The HAS-BLED score and ABC-bleeding score, as well as other potential factors, were explored to predict bleeding risk.

Results

In this observational study, 8.0% and 0.9% of the whole population suffered from bleeding and thromboembolic events, respectively. After adjusting for known factors related to bleeding, mitral regurgitation (MR, p for trend &lt;0.001) and body mass index (BMI, odds ratio (OR) = 0.920, 95% CI 0.852–0.993, p = 0.033) were the most significant ones. C-indexes of the HAS-BLED score and ABC-bleeding score for bleeding were 0.558 (0.492–0.624) and 0.585 (0.515–0.655), respectively. The incorporation of MR and BMI significantly improved the predictive value based on HAS-BLED score (C-index = 0.650, 95% CI 0.585–0.715, p = 0.004) and ABC-bleeding score (C-index = 0.671, 95% CI 0.611–0.731, p &lt; 0.001). The relative risk of mild-moderate MR was 4.500 (95% CI 1.625–12.460) in patients with AF having HAS-BLED = 1 and 4.654 (95% CI 1.496–14.475) in HAS-BLED ≥ 2, while it was not observed in patients with HAS-BLED = 0 (p = 0.722).

Conclusion

More severe MR and lower BMI are associated with a higher incidence of perioperative bleeding, which helps improve the predictability of increased individual bleeding risk of a patient with nonvalvular AF who has received CA therapy and oral anticoagulants.

Assessment and mitigation of bleeding risk in atrial fibrillation and venous thromboembolism: A Position Paper from the ESC Working Group on Thrombosis, in collaboration with the European Heart Rhythm Association, the Association for Acute CardioVascular Care and the Asia-Pacific Heart Rhythm Society

Whilst there is a clear clinical benefit of oral anticoagulation (OAC) in patients with atrial fibrillation (AF) and venous thromboembolism (VTE) in reducing the risks of thromboembolism, major bleeding events (especially intracranial bleeds) may still occur and be devastating. The decision to initiate and continue anticoagulation is often based on a careful assessment of both the thromboembolism and bleeding risk. The more common and validated bleeding risk factors have been used to formulate bleeding risk stratification scores, but thromboembolism and bleeding risk factors often overlap. Also, many factors that increase bleeding risk are transient and modifiable, such as variable international normalized ratio values, surgical procedures, vascular procedures, or drug-drug and food-drug interactions. Bleeding risk is also not a static 'one off' assessment based on baseline factors but is dynamic, being influenced by ageing, incident comorbidities, and drug therapies. In this Consensus Document, we comprehensively review the published evidence and propose a consensus on bleeding risk assessments in patients with AF and VTE, with the view to summarizing 'best practice' when approaching antithrombotic therapy in these patients. We address the epidemiology and size of the problem of bleeding risk in AF and VTE, review established bleeding risk factors, and summarize definitions of bleeding. Patient values and preferences, balancing the risk of bleeding against thromboembolism are reviewed, and the prognostic implications of bleeding are discussed. We propose consensus statements that may help to define evidence gaps and assist in everyday clinical practice.

Role of New Potential Biomarkers in the Risk of Thromboembolism in Atrial Fibrillation

Ischemic stroke risk in atrial fibrillation differs from patient to patient, depending on numerous variables. Many attempts have been made to translate this difference into simple numbers and to compare it to the hemorrhagic risk of anticoagulation. Different clinical scores have been studied to define a clear strategy. One score, the CHA₂DS₂-VASc score, has been extensively and successfully applied worldwide. Nevertheless, it is not yet the “perfect instrument”. Many proposals have been made to integrate its clinical parameters with some biomarkers to improve its predictive power. This short review describes some of these biomarkers and their possible implications in potentiating the efficacy of clinical scores.