Risk of stroke or systemic embolism in atrial fibrillation patients treated with warfarin: a systematic review and meta-analysis

Renal Outcomes of Rhythm Control in Patients Recently Diagnosed With Atrial Fibrillation

BACKGROUND

Atrial fibrillation (AF) is associated with impaired renal function and chronic kidney disease (CKD).

OBJECTIVES

This study assessed the effects of rhythm control on renal function compared with rate control among patients recently diagnosed with AF.

METHODS

A total of 20,886 patients with AF and available baseline estimated glomerular filtration rate (eGFR) data undergoing rhythm control (antiarrhythmic drugs or ablation) or rate control therapy, initiated within 1 year of AF diagnosis in 2005 to 2015, were identified from the Korean National Health Insurance Service database. The composite outcome of ≥30% decline in eGFR, acute kidney injury, kidney failure, or death from renal or cardiovascular causes was compared with the use of propensity overlap weighting between rhythm or rate control strategies in patients with or without significant CKD (eGFR <60 mL/min/1.73 m2).

RESULTS

Of the included patients (median age 62 years, 32.7% female), 2,213 (10.6%) had eGFR <60 mL/min/1.73 m2. Among patients with significant CKD, early rhythm control, compared with rate control, was associated with a lower risk of the primary composite outcome (weighted incidence rate: 2.77 vs 3.92 per 100 person-years; weighted HR: 0.70; 95% CI: 0.52-0.95). In patients without significant CKD, there was no difference in the risk of the primary composite outcome between rhythm and rate control groups (weighted incidence rate: 3.41 vs 3.21 per 100 person-years; weighted HR: 1.06; 95% CI: 0.96-1.18). No differences in safety outcomes were found between rhythm and rate control strategies in patients without or with significant CKD.

CONCLUSIONS

Among patients with AF and CKD, early rhythm control was associated with lower risks of adverse renal outcomes than rate control was.

A Survey of Saudi General Practitioners on the Use of Thromboprophylaxis Guidelines and Risk Assessment Tools in Atrial Fibrillation

Clinical practice guidelines advise patients with atrial fibrillation who are at risk for stroke to undergo thromboprophylaxis with oral anticoagulants. However, it is noted that guidelines are not always followed. We sought to learn how Saudi Arabian general practitioners (GPs) self-reported using risk assessment tools and atrial fibrillation clinical practice guidelines created by cardiology associations, as well as how GPs felt about the resources that were available. Through the use of a self-administered questionnaire, we carried out a cross-sectional survey. A total of two-hundred GPs participated in the study. The guidelines were frequently used when a clinical decision regarding anticoagulation therapy appeared difficult (n = 57, 28.4%). The most predominant strengths of participants' chosen clinical guidelines were clear recommendations (n = 56, 27.9%), easy-to-follow algorithms (n = 39, 16.9%), detailed recommendations supported by evidence (n = 34, 16.9%), and online availability (n = 27, 13.4%). Many respondents said they used a formal stroke risk assessment tool in addition to their clinical judgment as a GP for most decisions (60%). Most respondents preferred using the CHA2DS2-VASc (n = 106, 52.7%), CHA2DS2-VA (n = 45, 22.4%), CHADS2 (n = 35, 17.4%), and GARFIELD (n = 14, 7.0%). HAS-BLED (n = 100, 49.8%) and HEMORR2HAGES (n = 50, 24.9%) were the most frequently utilized formal tools for assessing the risk of bleeding among GPs. Over half of the participants referred to guidelines when deciding thromboprophylaxis in patients with atrial fibrillation. Additionally, many respondents used formal procedures for assessing the risks of bleeding and stroke in addition to their clinical judgement in their roles as GPs. The guideline was assessed as being extremely helpful overall by GPs who used it to make thromboprophylaxis decisions.

Gerinnungsmanagement in der schweren, fortgeschrittenen Niereninsuffizienz

Patienten mit chronischer Niereninsuffizienz (CKD) haben ein hohes Risiko für nicht valvuläres Vorhofflimmern (NVAF) und häufig ein höheres Risiko für venöse Thromboembolien (VTE) aufgrund ihrer Grunderkrankungen wie z. B. Diabetes. Bisher kamen Vitamin-K-Antagonisten (VKA) auch bei diesen Patienten in Deutschland zum Einsatz. VKA haben ein erhöhtes Blutungsrisiko und werden als Risikofaktor für eine Verschlechterung der Nierenfunktion und/oder Gefäßsituation (Athero- und Mediasklerose) von Patienten diskutiert. Aus diesen Gründen und den vorliegenden Studiendaten werden deshalb direkt wirkende orale Antikoagulanzien (DOAC) auch bei Patienten mit NVAF und CKD (G1–G3) in den Leitlinien empfohlen. Allerdings kann keine klare Empfehlung für den Einsatz von DOAC bei Dialysepatienten gegeben werden. Heparine spielen in diesem Zusammenhang nur eine untergeordnete Rolle.

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.

Incidence and Risk Factors for Residual Adverse Events Despite Anticoagulation in Atrial Fibrillation: Results From Phase II/III of the GLORIA-AF Registry

Background Residual risk of ischemic stroke despite anticoagulation in patients with atrial fibrillation (AF) represents a significant clinical issue that remains unaddressed. We aimed to evaluate the incidence and risk factors for residual adverse events in AF. Methods and Results Using data from phase II/III of the prospective GLORIA-AF (Global Registry on Long-Term Oral Anti-thrombotic Treatment in Patients With Atrial Fibrillation) registry, we studied anticoagulated patients with newly diagnosed AF and an increased risk of stroke (CHA2DS2-VASc ≥1). The primary outcome of interest was ischemic stroke. Secondary outcomes were all-cause death, cardiovascular death and myocardial infarction. A total of 22 410 patients were included; median age 65 (interquartile range 71-78) and 10 044 (44.8%) were female. During a median follow-up period of 3.0 (interquartile range 2.2-3.1) years, the incidence of ischemic stroke was 0.60 (95% CI, 0.54-0.67) per 100-PYs, all-cause death 3.22 (95% CI, 3.08-3.37) per 100-PYs, cardiovascular death 1.08 (95% CI, 1.00-1.16) per 100-PYs and myocardial infarction 0.59 (95% CI, 0.53-0.66) per 100-PYs. Using multivariable Cox proportional hazards analysis, independent predictors of residual ischemic stroke were age (HR 1.05 [95% CI, 1.03-1.07]), diabetes (HR 1.42 [95% CI, 1.08-1.87]), prior thromboembolism (HR 2.27 [95% CI, 1.73-2.98]) and use of antiarrhythmic drugs (HR 0.66 [95% CI, 0.47-0.92]). The incidence of ischemic stroke was comparable among patients treated with nonvitamin K antagonist oral anticoagulants versus vitamin K antagonist; however, there were differences in the independent predictors between both groups. Conclusions Patients with AF remain at significant residual risk of developing complications including ischemic stroke despite anticoagulation therapy. Further efforts among these patients should be directed at the management of modifiable risk factors that contribute to this risk. Registration URL: http://www.clinicaltrials.gov; Unique identifiers: NCT01468701, NCT01671007 and NCT01937377.

High Plasma Concentration of Apolipoprotein C-III Confers an Increased Risk of Cerebral Ischemic Events on Cardiovascular Patients Anticoagulated With Warfarin

Introduction

Apolipoprotein C-III (Apo CIII) is a crucial regulator of triglyceride-rich lipoproteins (TRLs) and influences the risk of cardiovascular diseases. High levels of Apo CIII have been also associated with cerebrovascular events and earlier works showed procoagulant effects of Apo CIII. The main aim was to assess whether the plasma concentration of Apo CIII could confer an increased risk of cerebral ischemic events in anticoagulated patients at high-risk of cardioembolism.

Methods

We systematically checked medical records and quantified cerebral ischemic events in a selected cohort of 118 subjects [median age 68 with interquartile range (IQR) 59–75 years, 66.9% males, 52.5% with coronary artery disease (CAD)], taking anticoagulant therapy with warfarin because of atrial fibrillation (AF) and/or mechanical prosthetic heart valves. All the subjects, enrolled between May 1999 and December 2006, were prospectively followed until death or July 31, 2018. Assessments of complete plasma lipid and apolipoprotein profiles, including Apo A-I, B, CIII, and E, were available for all subjects at enrollment.

Results

After a median follow-up of 109 months (IQR, 58–187), 24 subjects (20.3%) had cerebral ischemic events: stroke (n = 15) and TIA (n = 9). Subjects with plasma concentration of Apo CIII above the median value (10.3 mg/dL) had an about three-fold increased risk of stroke/TIA than those with lower levels of Apo C-III [hazard ratio 3.08 (95%CI, 1.22–7.77)]. This result was confirmed in multiple Cox regression models adjusted for gender, age, CAD, AF, diabetes, hypertension, plasma lipids, and CHA₂DS₂-VASc score. By stratifying the sample on the basis of Apo CIII level and CHA₂DS₂-VASc score, an additive effect was observed with the highest risk in subjects with both high Apo C-III concentration and CHA₂DS₂-VASc score.

Conclusion

High Apo CIII plasma levels may be associated with an increased risk of ischemic stroke/TIA in high-risk cardiovascular patients anticoagulated with warfarin.

Prevalence and predictors of left atrial thrombosis in atrial fibrillation patients treated with non-vitamin K antagonist oral anticoagulants

BACKGROUND

Few data are available regarding the prevalence of left atrium (LA) thrombi in atrial fibrillation (AF) patients treated with non-vitamin K antagonist oral anticoagulants (NOACs). Methods: We evaluated the prevalence and predictors of LA/LA appendage (LAA) thrombi in non-valvular AF patients treated with NOACs referring to a single centre for a scheduled electrical cardioversion (ECV) or catheter ablation (CA). Transesophageal echocardiography (TEE) was performed within 12 h prior to the index procedure.

RESULTS

A total of 352 consecutive patients with non-valvular AF treated with NOACs were included in this analysis (ECV group n = 176 and CA group n = 176) between 2013 and 2018. 85 patients (24.2%) were on dabigatran, 150 (42.7%) on rivaroxaban, 104 (29.6%) on apixaban and 13 (3.7%) on edoxaban. A LA/LAA thrombus was detected by TEE in 27 (7.7%) patients, 18 in the ECV group and nine in the ablation group; 18 (5.1%) patients presented dense LA/LAA spontaneous echo contrast (SEC). Predictors of LA/LAA thrombi were a CHA₂DS₂-VASc score > 3 (OR 4.54, 95% CI 1.50 - 13.70, p value = .007) and obesity (OR 6.01, 95% CI 1.95 - 18.50, p value = .001).

CONCLUSIONS

Among real-world patients with non-valvular AF treated with NOACs, we found a high incidence of LA/LAA thrombi compared to previous reports. The main predictors of LA/LAA thrombosis were a CHA₂DS₂-VASc score > 3 and obesity.

Residual Stroke Risk in Atrial Fibrillation

AF contributes to increased stroke risk via various mechanisms, including deranged blood constituents, vessel wall abnormalities and abnormal blood flow. This excess risk is frequently managed with anticoagulation therapy, aimed at preventing thromboembolic complications. Yet, a significant proportion of patients with AF remain at high residual stroke risk despite receiving appropriate dose-adjusted anticoagulation. This article explores the residual stroke risk in AF and potential therapeutic options for these patients.

Knowledge of Anticoagulation Among Saudi Patients With Atrial Fibrillation: A Cross-Sectional Study

Background Knowledge about oral anticoagulant treatment can impact treatment outcomes in patients with atrial fibrillation. However, evidence is scarce regarding the knowledge of oral anticoagulants among Saudi patients with atrial fibrillation. Hence, this study aimed to assess the level of anticoagulation knowledge among patients with atrial fibrillation taking oral anticoagulants. Methodology A survey using a cross-sectional study design was conducted among patients with a confirmed diagnosis of atrial fibrillation in a tertiary care setting. The Oral Anticoagulation Knowledge Tool (AKT), a 33-item, self-administered questionnaire, was used to assess the knowledge of anticoagulation. Results A total of 290 patients with a median age of 67 years participated in the survey. More than half of those surveyed (56.2%) were females. Overall, 195 (67.2%) patients had an overall adequate anticoagulation knowledge. The median knowledge score of participants on warfarin was significantly higher than those on direct-acting oral anticoagulants (p < 0.001). Only age was found to be a predictor of AKT. Increasing age was associated with fewer odds of adequate AKT. For every one-year increase in age, the knowledge score decreased by 0.08 (95% confidence interval: -0.13 to -0.04). Conclusions This study found significant knowledge gaps among Saudi patients with atrial fibrillation taking oral anticoagulants. Advancing age was inversely associated with oral anticoagulation knowledge.

BNP combined with echocardiographic parameters to predict the risk of cardioembolic stroke

BACKGROUND

Previous studies have found that BNP and some indicators of cardiac structure and function are closely associated with atrial fibrillation, so we aim to investigate the potential role of BNP and echocardiographic parameters to identify the acute ischemic stroke with atrial fibrillation patients who have high risks of cardioembolic stroke based on it.

METHODS

436 AIS patients were divided into an AF group and non-AF group on the basis of the electrocardiogram and Holter results. Then we compared vascular risk factors, laboratory test indicators, and echocardiographic parameters among different groups.

RESULTS

AIS with AF group had significantly higher age, CHD, previous medication, creatinine, d-dimer, fibrinogen, CRP, BNP, LAD, LVDd, LVDs and lower cholesterol, triglyceride, LDL and ejection fraction than the non-AF group (P < 0.05). Increased BNP, LAD, LVDd, LVDs and ejection fraction reduction were independent risk factors to predict cardioembolic stroke. BNP and LAD could be the two most effective indicators of the high risk of cardioembolic stroke. The area under the curve (AUC) of BNP and LAD were 0.791 [95%CI (0.743-0.838), p < 0.001), 0.786 [95%CI (0.739-0.833), p < 0.001]. The combined score we designed improved the prediction effect of single-indicator. The AUC of it was 0.822 with a sensitivity of 69.5% and specificity of 83.9%.There was an apparent positive correlation between BNP and LAD in AIS patients (r = 0.327, P < 0.001).

CONCLUSION

BNP combined with echocardiographic parameters has outstanding value to predict the risk of cardioembolic stroke, especially for BNP and LAD.

Associations between model-predicted rivaroxaban exposure and patient characteristics and efficacy and safety outcomes in patients with non-valvular atrial fibrillation

Rivaroxaban exposure and patient characteristics may affect the rivaroxaban benefit–risk balance. This study aimed to quantify associations between model-predicted rivaroxaban exposure and patient characteristics and efficacy and safety outcomes in patients with non-valvular atrial fibrillation (NVAF), using data from the phase 3 ROCKET AF trial (NCT00403767). In ROCKET AF, 14,264 patients with NVAF were randomized to rivaroxaban (20 mg once daily [OD], or 15 mg OD if creatinine clearance was 30–49 mL/min) or dose-adjusted warfarin (median follow-up: 707 days); rivaroxaban plasma concentration was measured in a subset of 161 patients. In this post hoc exposure–response analysis, a multivariate Cox model was used to correlate individual predicted rivaroxaban exposures and patient characteristics with time-to-event efficacy and safety outcomes in 7061 and 7111 patients, respectively. There was no significant association between model-predicted rivaroxaban trough plasma concentration (C_trough) and efficacy outcomes. Creatinine clearance and history of stroke were significantly associated with efficacy outcomes. C_trough was significantly associated with the composite of major or non-major clinically relevant (NMCR) bleeding (hazard ratio [95th percentile vs. median]: 1.26 [95% confidence interval 1.13–1.40]) but not with major bleeding alone. The exposure–response relationship for major or NMCR bleeding was shallow with no clear threshold for an acceleration in risk. History of gastrointestinal bleeding had a greater influence on safety outcomes than C_trough. These results support fixed rivaroxaban 15 mg and 20 mg OD dosages in NVAF. Therapeutic drug monitoring is unlikely to offer clinical benefits in this indication beyond evaluation of patient characteristics.

Plasma D-dimer level is associated with clinical outcomes in patients with atrial fibrillation related acute ischemic stroke after pneumonia

Background

Pneumonia is related to poor prognosis in acute ischemic stroke (AIS), and its risk might be higher in atrial fibrillation (AF) related AIS with elevated plasma D-dimer. The aim of our study was to investigate the prognostic value of D-dimer for predicting clinical outcome of AF-related AIS with pneumonia.

Method

AF-related AIS patients with pneumonia were prospectively enrolled. Receiver operating characteristic (ROC) curve was used to determine the optimal D-dimer point for 3-month mortality and death/severe disability. The associations between the D-dimer and 3-month mortality and death/severe disability were assessed by multivariable logistic regression analysis.

Results

A total of 415 patients were enrolled in this study. ROC curve analysis showed that the optimal cut point of D-dimer for 3-month death/severe disability and mortality were D-dimer≥2.35 mg/l and D-dimer≥3.35 mg/l, respectively. Multivariable logistic regression analysis showed that D-dimer≥2.35 mg/l [adjusted odds ratio (aOR) 5.99, 95% confidence interval (CI): 3.04–11.83, P<0.001], higher NIHISS score (aOR:1.53, 95% CI: 1.38–1.69, P<0.001) and larger infarct volume (aOR 1.01, 95% CI: 1.01–1.02, P<0.001) were associated with increased risk of 3-month death/severe disability), and anticoagulant was associated with decreased risk of death/severe disability (aOR:0.21, 95% CI: 0.09–0.47, P<0.001). Higher NIHISS score (aOR:1.64, 95% CI: 1.38–1.94, P<0.001), older age (aOR 1.08, 95% CI: 1.02–1.14, P = 0.007), D-dimer≥3.35 mg/l (OR 8.49, 95% CI: 4.13–17.84,P<0.001), larger infarct volume (aOR 1.02, 95% CI: 1.00–1.03, P = 0.014), and higher CRUB-65 score (aOR 6.43, 95% CI: 3.10–13.34, P<0.001) were associated with increased risk of 3-month mortality.

Conclusions

AF-related AIS patients with concurrent high D-dimer and pneumonia increased risk of 3-month mortality and death/severe disability, plasma D-dimer may have predictive value in outcome after AF-related AIS with pneumonia.

Stroke and Novel Coronavirus Infection in Humans: A Systematic Review and Meta-Analysis

Background: As the world witnessed the devastation caused by the coronavirus disease 2019 (COVID-19) outbreak, a growing body of literature on COVID-19 is also becoming increasingly available. Stroke has increasingly been reported as a complication of COVID-19 infection. However, a systematic synthesis of the available data has not been conducted. Therefore, we performed a systematic review and meta-analysis of currently available epidemiological, clinical, and laboratory data related to both stroke and COVID-19 infection. Methods: We systematically searched Medline, Cinahl, and PubMed for studies related to stroke and COVID-19 from inception up to June 4, 2020. We selected cohort studies, case series, and case reports that reported the occurrence of stroke in COVID-19 patients. A fixed-effects model was used to estimate the pooled frequency of stroke in COVID-19 patients with a 95% confidence interval (CI). Results: Twenty-eight studies were included in the systematic review and seven studies for the meta-analysis. The pooled frequency of stroke in COVID-19 patients was 1.1% (95% CI: 0.8, 1.3). The heterogeneity was low (I 2 = 0.0%). Even though the frequency of stroke among patients having COVID-19 infection was low, those with concomitant COVID-19 infection and stroke suffered from a more severe infection and eventually had a poorer prognosis with a higher mortality rate (46.7%) than COVID-19 alone. Many COVID-19 patients shared the common traditional risk factors for stroke. We noted that ischemic stroke involving the anterior circulation with large vessels occlusion is the most common type of stroke with more strokes seen in multi-territorial regions, suggesting systemic thromboembolism. An elevated level of D-dimers, C-reactive protein, ferritin, lactic acid dehydrogenase, troponin, ESR, fibrinogen, and a positive antiphospholipid antibody were also noted in this review. Conclusions: The occurrence of stroke in patients with COVID-19 infection is uncommon, but it may pose as an important prognostic marker and indicator of severity of infection, by causing large vessels occlusion and exhibiting a thrombo-inflammatory vascular picture. Physicians should be made aware and remain vigilant on the possible two-way relationship between stroke and COVID-19 infection. The rate of stroke among patients with COVID-19 infection may increase in the future as they share the common risk factors.

Effectiveness and Safety of Restarting Oral Anticoagulation in Patients with Atrial Fibrillation after an Intracranial Hemorrhage: Analysis of Medicare Part D Claims Data from 2010-2016

BACKGROUND

In patients with atrial fibrillation (AF) who survive an anticoagulant-related intracranial hemorrhage (ICH), the benefits of restarting oral anticoagulation (OAC) remain unclear.

OBJECTIVE

In this study, we sought to determine the effectiveness and safety associated with resumption of OAC in atrial fibrillation patients who survive an ICH.

METHODS

Using 2010-2016 Medicare claims data, we identified patients with non-valvular AF who experienced an OAC-related ICH and survived at least 6 weeks after the ICH (n = 1502). The primary outcomes included the composite of ischemic stroke and transient ischemic attack (TIA), thromboembolism (TE), a composite of ischemic stroke/TIA and TE, recurrent ICH, and all-cause mortality. We constructed Cox proportional hazard models to evaluate the association between post-ICH OAC resumption, which was measured in a time-dependent manner, and the risk of primary outcomes, while controlling for a comprehensive list of covariates.

RESULTS

Among patients who survived an ICH, 69% reinitiated OAC within 6 weeks of the event, and among those who resumed OAC, 83% restarted warfarin. There was no significant difference in the risk of ischemic stroke/TIA (hazard ratio [HR] 0.87, 95% confidence interval [CI] 0.62-1.21), TE (HR 0.85, 95% CI 0.55-1.32), and ischemic stroke/TIA/TE (HR 0.81, 95% CI 0.61-1.07) between post-ICH OAC use and non-use. Post-ICH OAC use was associated with a lower risk of recurrent ICH (HR 0.62, 95% CI 0.41-0.95) and all-cause mortality (HR 0.48, 95% CI 0.37-0.62) compared with non-OAC use.

CONCLUSIONS

In AF patients who survived an ICH, restarting OAC was not associated with a greater risk of recurrent ICH. Evidence from randomized controlled studies is needed to further clarify the clinical benefit of restarting OAC in this high-risk population. Further evaluation of which individuals benefit from restarting OAC is also needed to provide more clinical guidance.

Residual risks of ischaemic stroke and systemic embolism among atrial fibrillation patients with anticoagulation: large-scale real-world data (F-CREATE project)

OBJECTIVE

Among patients with atrial fibrillation, the risks of ischaemic stroke and systemic embolism (IS/SE) are high even with effective anticoagulation. Using large-scale, real-world data from Japan, this study aims to clarify residual risks of IS/SE attributable to modifiable risk factors among patients with atrial fibrillation who are taking oral anticoagulants.

METHODS

The study design we employed was a retrospective cohort. Health check-ups and insurance claims data of Japanese health insurance companies were accumulated from January 2005 to June 2017. We identified 11 848 participants with atrial fibrillation who were on oral anticoagulants during the study period. We set the modifiable risk factors as hypertension, diabetes and dyslipidaemia. A Cox proportional hazards model was used to obtain the effects of the risk factors for IS/SE.

RESULTS

During an average of 3 years' follow-up, 200 cases of IS/SE occurred (incidence rate 0.57 per 100 person-years). In multivariable analyses, older age (65-74 vs <65 years; adjusted HR 2.02 (95% CI 1.49 to 2.73)), hypertension (adjusted HR 1.41 (1.04 to 1.92)) and dyslipidaemia (adjusted HR 1.46 (1.07 to 1.98)) were significantly associated with increased risk of IS/SE. Percentage of IS/SE risk attributable to modifiable risk factors (hypertension, diabetes and dyslipidaemia) was 30.0% (16.1% to 41.6%).

CONCLUSION

Among patients with atrial fibrillation on anticoagulant therapy, approximately one-third of the residual risks were estimated to be attributable to modifiable risk factors such as hypertension, diabetes and dyslipidaemia.

Increased Incident Ischemic Stroke Risk in Advanced Kidney Disease: A Large-Scale Real-World Data Study

INTRODUCTION

Evidence using real-world data is sparse regarding the effects of oral anticoagulants (OACs) among patients with kidney disease. The aim of this study was to investigate the effects of kidney disease on ischemic stroke (IS) or systemic embolism (SE) among patients taking OAC, using large-scale real-world data in Japan.

METHODS

This was a retrospective cohort study using claims data and health checkup data from health insurance associations in Japan, from January 2005 to June 2017. We enrolled 21,581 patients diagnosed with atrial fibrillation (AF). Of the total population, 11,848 (54.9%) patients were taking OAC. A Cox proportional hazards model was used to examine the effect of kidney disease on IS/SE with or without OAC.

RESULTS

During follow-up, 208 participants who were not taking OAC (mean follow-up 2.6 years) and 200 who were taking OAC (mean follow-up 3.0 years) experienced IS/SE. The % IS/SE incidence rates with and without kidney disease were 2.42/person-year and 0.63/person-year in the total population, 3.66/person-year and 0.76/person-year in the group without OAC use, and 1.52/person-year and 0.55/person-year in patients with OAC use, respectively. Hazard ratios (HRs) and 95% confidence intervals (CIs) of kidney disease for IS/SE were high, irrespective of OAC, even after adjustment: adjusted HR 2.62 (95% CI: 1.72-3.99) without OAC and adjusted HR 2.03 (95% CI: 1.20-3.44) with OAC; p = 0.193 for interaction between no OAC and OAC. Although bleeding risk was also high for kidney disease irrespective of OAC use (HR 2.93 [95% CI: 2.27-3.77] in the total population, HR 3.08 [95% CI: 2.15-4.43] in the group without OAC, and HR 2.73 [95% CI: 1.90-3.91] in the group with OAC use), net clinical benefit indicated that the benefit of OAC use exceeded the risk of bleeding: HR 4.50 (95% CI: 0.76-8.23) among those with kidney disease and HR 0.35 (95% CI: 0.04-0.66) among those without kidney disease.

CONCLUSION

Although we found that OAC use was effective and recommended for patients with AF, advanced kidney disease is still an independent risk factor for IS/SE, even in patients taking OAC. Physicians should be aware of this risk and strictly control modifiable risk factors, regardless of OAC use.

Evaluating Effectiveness and Safety in Chronic Kidney Disease with Atrial Flutter Using an Anticoagulation Strategy

Background and objectives: Recent randomized trials of oral antithrombotic drugs with atrial flutter (AFL) excluded patients with renal impairment because of their increased risk of bleeding. To date, no relevant studies have assessed the effectiveness and safety of different antithrombotic drugs in chronic kidney disease (CKD) patients with AFL. This cohort study evaluated the effectiveness and safety of different antithrombotic drugs in CKD patients with AFL. This study also investigated the risk of cardiovascular events from antithrombotic drugs through different risk profiles of stroke stratified by the CHA₂DS₂-VASc score. Materials and Methods: This cohort study was performed in patients with AFL and CKD who were extracted from the National Health Insurance (NHI) Database in Taiwan. Oral antithrombotic therapy (oral anticoagulants (OAC) or antiplatelets (APT)) was administered to patients who had been diagnosed with AFL after being diagnosed with CKD between 2011 and 2015. Primary outcomes, including ischemic stroke, systemic embolism, and composite of stroke, and secondary outcomes, including major adverse cardiac events (MACEs), major bleeding, all-cause mortality, and cardiovascular-related death, were examined. Results: A total of 2468 patients were included in this study. The results showed no statistically significant differences in the risk of primary outcomes. For the secondary outcomes, there were also no statistically significant differences in the risk of MACEs and major bleeding. However, the pooled results indicated that the hazard ratio (HR) for all-cause mortality with OAC was 0.24 (95% confidence interval (CI) = 0.10–0.55) compared with combination therapy, and the HR for APT compared with OAC was 2.86 (95% CI = 1.48–5.53). Conclusions: In the studied population, OAC or APT alone were proved equally effective for stroke prophylaxis. Furthermore, OAC might reduce the all-cause mortality rate compared with APT and should be considered as the first choice of oral antithrombotic drugs in patients with AFL and CKD.

Prognostic value of von Willebrand factor for patients with atrial fibrillation: a meta-analysis of prospective cohort studies

BACKGROUND

It is unknown whether an abnormal level of von Willebrand factor (vWF) is correlated with the prognosis of patients with atrial fibrillation (AF) and current findings are controversial. This meta-analysis aimed to evaluate the association between vWF levels and the clinical prognosis of patients with AF.

METHODS

We searched prospective cohort studies on PubMed, Embase, Web of Science, Cochrane Library and WanFang databases for vWF and adverse events of AF from inception of the databases to July 2019. The risk ratios of all-cause death, cardiovascular death, major adverse cardiac events (MACE), stroke and bleeding prognosis in patients with AF were analysed using a fixed-effects model or random-effects model, and all included studies were evaluated with heterogeneity and publication bias analysis.

RESULTS

Twelve studies which included 7449 patients with AF were used in the meta-analysis. The average age was 71.3 years and the average follow-up time was 3.38 years. The analysis found that high vWF levels were associated with increased risks of all-cause death (RR 1.56; 95% CI 1.16 to 2.11, p=0.00400), cardiovascular death (RR 1.91; 95% CI 1.20 to 3.03, p=0.00600), MACE (RR 1.83; 95% CI 1.28 to 2.62, p=0.00090), stroke (RR 1.69; 95% CI 1.08 to 2.64, p=0.02000) and bleeding (RR 2.01; 95% CI 1.65 to 2.45, p<0.00001) in patients with AF.

CONCLUSIONS

vWF is a risk factor for poor prognosis of AF, and patients with higher vWF levels have a higher risk of all-cause death, cardiovascular death, MACE, stroke and bleeding.

Safety of Using Direct Oral Anticoagulants in Patients with Atrial Fibrillation and Chronic Kidney Disease

The purpose of this review is to examine the possibilities and prospects for the use of direct oral anticoagulants for the prevention of thromboembolic complications in patients with atrial fibrillation and chronic kidney disease. Chronic kidney disease is an independent risk factor for cardiovascular complications. Atrial fibrillation is associated with a higher risk of developing chronic kidney disease and more rapid progression of existing renal pathology. The presence of chronic kidney disease in atrial fibrillation on the one hand leads to an increased risk of thromboembolism, and on the other to an increased risk of bleeding when using anticoagulants. The standard for the prevention of thromboembolic complications in atrial fibrillation, including those with concomitant renal pathology, was considered warfarin for many years. However, modern studies have shown that the use of warfarin may enhance vascular calcification in patients with chronic kidney disease, which in turn may lead to an increased risk of ischemic strokes.

Analyzing clinical recommendations, randomized studies, meta-analyzes and a systematic review on the use of anticoagulants in patients with atrial fibrillation and renal pathology, revealed the advantage of using direct oral anticoagulants over warfarin at stage 1-3 of chronic kidney disease. Data on the use of direct oral anticoagulants with a more pronounced renal dysfunction and in patients on dialysis is limited due to the lack of a sufficient number of large randomized studies. Due to the presence of renal clearance in all oral anticoagulants, their pharmacokinetics changes to some extent with a decrease in the glomerular filtration rate, which requires dose adjustment of drugs depending on creatinine clearance. Therefore, the use of anticoagulants for the prevention of thromboembolic complications during atrial fibrillation requires special attention in patients with chronic kidney disease.

Risk factors for ischemic stroke in patients with non-valvular atrial fibrillation and therapeutic international normalized ratio range

INTRODUCTION

Atrial fibrillation (AF) is the most common cause of ischemic stroke (IS). Atrial fibrillation patients are recommended to use oral anticoagulants (OACs) as part of prevention against IS. However, despite having a therapeutic intensity of OAC therapy, IS can still occur in such patients. The aim of our study was to examine the configuration of IS risk factors in patients with non-valvular atrial fibrillation (NVAF) and within the therapeutic INR range (TINR).

MATERIAL AND METHODS

Our retrospective study involved 1835 patients with a recent IS. The experimental group consisted of 154 patients with acute IS, NVAF and TINR. The control group consisted of 1681 patients with acute IS but without AF.

RESULTS

Patients with IS, NVAF and TINR were significantly older and more often female than patients with IS without NVAF (p < 0.001 and p < 0.001, respectively). In these patients, diabetes mellitus, dyslipidemia, hypertension, coronary heart disease, smoking and previous IS were significantly more frequent than in the patients with IS without NVAF (p = 0.036, p = 0.002, p < 0.001, p < 0.001, p < 0.001, p = 0.003). Based on a univariable and multivariable logistic regression model, we found that in the group of patients who suffered a stroke despite TINR compared to patients with IS without AF there were more smokers (OR = 20.337; OR = 147.589) and patients with previous stroke (OR = 6.556; OR = 11.094), hypertension (OR = 3.75; OR = 2.75) and dyslipidemia (OR = 2.318; OR = 2.294).

CONCLUSIONS

The group of patients with NVAF and TINR is significantly more burdened by other independent common risk factors for stroke.

Atrial Fibrillation in Older People: Concepts and Controversies

Atrial fibrillation (AF) is the commonest cardiac rhythm abnormality and has a significant disease burden. Amongst its devastating complications is stroke, the risk of which increases with age. The stroke risk in an older person with AF is therefore tremendous, and oral-anticoagulation (OAC) therapy is central to minimizing this risk. The presence of age-associated factors such as frailty and multi-morbidities add complexity to OAC prescription decisions in older patients and often, OAC is needlessly withheld from them despite a lack of evidence to support this practice. Generally, this is driven by an over-estimation of the bleeding risk. This review article provides an overview of the concepts and controversies in managing AF in older people, with respect to the existing evidence and current practice. A literature search was conducted on Pubmed and Cochrane using keywords, and relevant articles published by the 1st of May 2019 were included. The article will shed light on common misconceptions that appear to serve as rationale for precluding OAC and focus on clinical considerations that may aid OAC prescription decisions where appropriate, to optimize AF management using an integrated, multi-disciplinary care approach. This is crucial for all patients, particularly older individuals who are most vulnerable to the deleterious consequences of this condition.

Warfarin Use and Mortality, Stroke, and Bleeding Outcomes in a Cohort of Elderly Patients with non-Valvular Atrial Fibrillation

Aims

To determine exposure to warfarin and the associated outcomes in a population of older patients with non-valvular atrial fibrillation (NVAF).

Methods

Cohort study of patients aged 65-89 years admitted to hospital July 2003-December 2008 with newly-diagnosed or pre-existing AF. Outcomes at three years among one-year survivors post-index admission (landmark date) were all-cause mortality, stroke/systemic thromboembolism (stroke/TE) and bleeding. Multivariate Cox models were used to identify factors associated with each outcome.

Results

AF was the principal diagnosis for 27.5% of 17,336 index AF admissions. Of 14,634 (84.4%) patients alive at one-year 1,384 (9.5%) died in the following year. Vascular disease (42%) was the most frequent cause of death.Warfarin use, prior to the index admission and/or the 1-year landmark, did not exceed 40%.Compared to non-exposure or discontinuation at the index admission, initiation or persistence with warfarin prior to the landmark date was associated with reduced risk for all-cause mortality, a statistically non-significant reduction in risk for stroke/TE, and an increased risk for bleeding. Higher CHA2DS2-VASc scores were associated with increased risk for each outcome.

Conclusions

In a population-based cohort of hospitalised NVAF patients, the initiation and persistent use of warfarin was associated with lower all-cause mortality risk to three years, although reduction in risk for stroke/TE did not reach statistical significance. The apparent under-use of warfarin in this older, high-risk cohort reinforces the opportunity for further reduction in stroke/TE with the uptake of non-vitamin K oral anti-coagulants (NOACs) among those not prescribed, or not persistent with, warfarin.

Efficacy and safety of left atrial appendage closure in non-valvular atrial fibrillation in patients over 75 years

Percutaneous left atrial appendage closure (LAAC) may decrease risks of stroke and bleeding in elderly patients with non-valvular atrial fibrillation (NVAF), but it is still lacking of evidence. The present study aimed at evaluating the efficacy and safety of LAAC in patients with NVAF over 75 years. 351 patients with NVAF who underwent LAAC were retrospectively analyzed on the LAAC procedure characteristics and the clinical follow-up according to age (age ≥ 75 years or < 75 years). Out of the 351 patients, LAA were successfully closed in 347 patients (98.9%), including 341 with Watchman (WM) device and 6 with Amplatzer cardiac plug (ACP) device because of the WM device-incompatible anatomy. There were no significant differences in total LAAC success rate and procedure-related major complications within 7 days between the groups aged ≥ 75 years and aged < 75 years. After a nearly 2-year follow-up, there was an increased trend of major bleedings and all bleedings in the group aged ≥ 75 years, but there were no significant differences between both groups in all-cause death, cardiovascular death, stroke/TIA/system embolism, device thrombus and device gap (> 5 mm). Kaplan-Meier analysis revealed that the relative risk of annual thromboembolic events between the observed values and the expected ones based on CHA₂DS₂-VASc score in the group aged ≥ 75 years decreased more obviously (61.9% vs. 54.3%); however, the relative risk of bleedings between the observed values and the expected ones based on HAS-BLED score in the younger group aged < 75 years decreased more significantly (59.6% vs. 29.2%). LAAC in patients with advanced age (age ≥ 75 years), has the same level of efficacy, safety and feasibility as in the younger patients aged < 75 years. Thus, LAAC may be an ideal choice to prevent stroke in NVAF patients with advanced age.

A survey of opinion: When to start oral anticoagulants in patients with acute ischaemic stroke and atrial fibrillation?

INTRODUCTION

There is uncertainty regarding the optimal timing for initiation of oral anticoagulant treatment in patients with recent ischaemic stroke and atrial fibrillation. We surveyed the current UK practice and assessed clinician's opinions of when to use oral anticoagulant in recent stroke patients with atrial fibrillation.

PATIENTS AND METHODS

An online survey was sent to stroke physicians within the United Kingdom via their national societies.

RESULTS

One hundred and twenty-one clinicians responded to the survey. Ninety-five percent of responders agreed that there was uncertainty regarding timing of oral anticoagulant initiation after atrial fibrillation-related ischaemic stroke. Thirty-six percent of responders followed the '1-3-6-12' European Society of Cardiology guidelines recommendation. Uncertainty was greater in cases of moderate stroke than in cases of transient ischaemic attack (TIA), mild or severe stroke. Eighty-eight percent of responders would be willing to participate in a clinical trial of early versus later initiation of oral anticoagulant after stroke. Direct-acting oral anticoagulants were the preferred oral anticoagulant of choice.

DISCUSSION AND CONCLUSION

There is a lack of consensus amongst stroke physicians for when to initiate oral anticoagulant to prevent recurrence in stroke patients with atrial fibrillation. There is little uncertainty regarding TIA. A clinical trial assessing the use of early versus later initiation of direct-acting oral anticoagulant in patients with recent ischaemic stroke and atrial fibrillation would be beneficial.

The use of direct oral anticoagulants in chronic kidney disease

Increasing use of direct oral anticoagulants (DOACs) has made management of non-valvular atrial fibrillation and venous thromboembolism easier in most patients. But the presence of co-existing renal impairment could render the use of DOACs problematic because all of these drugs have varying degrees of renal excretion. In this paper we address misconceptions about the safety and efficacy of DOACs in moderate-severe renal impairment by presenting a summary of the literature from phase III trials and real-world studies. It also addresses the important consideration of correct estimate of renal function for DOAC dosing. It is hoped that the review will serve as a valuable resource for clinicians involved in anticoagulation decision-making in patients with renal impairment to guide the choice of most suitable agent. Accurate dosing is of particular relevance as registry data suggests it is done inconsistently and may be resulting in avoidable thromboembolic and bleeding events.

The impact of ischaemic stroke on atrial fibrillation-related healthcare cost: a systematic review

The aim of this study was to summarize healthcare costs incurred by patients with atrial fibrillation (AF) who developed ischaemic stroke, explore factors associated with increased cost, and highlight the importance of anticoagulation therapy for stroke prophylaxis. A systematic literature search of PubMed, EMBASE, Web of Science, and the health economic evaluation database was conducted up to December 2015. Studies focused on the cost and/or resource utilization of ischaemic stroke in patients with AF were included. Reported costs were converted to international dollars (I$) and adjusted to 2015 values. Alongside the narrative review of included studies, Spearman's correlation, independent-samples t-test, and one-way ANOVA were used to explore factors associated with cost differences between studies. Sixteen studies published from nine countries were identified. Based on currency conversion rates in 2015, ischaemic stroke-related healthcare costs were estimated to be I$41 420, I$12 895, and I$8184 for high-income, upper middle-income, and lower middle-income economies, respectively. Local GDP per capita accounted for ∼50% of the healthcare cost variation among countries. Major component of overall cost was from hospitalization. Ischaemic stroke incurring in patients with AF ≥75 years was 2.3 times that of their younger peers (P = 0.049). The economic burden from ischaemic stroke in patients with AF is considerable with positive association to country income. Clinicians and stakeholders should be aware of the importance of anticoagulation therapies in stroke prophylaxis, the occurrence of stroke, and the downstream economic burden on an increasingly ageing population.

Ischemic stroke across sexes: What is the status quo?

Stroke prevalence is expected to increase in the next decades due to the aging of the Western population. Ischemic stroke (IS) shows an age- and sex-dependent distribution in which men represent the most affected population within 65 years of age, being passed by post-menopausal women in older age groups. Furthermore, a sexual dimorphism concerning risk factors, presentation and treatment of IS has been widely recognized. In order to address these phenomena, a number of issue have been raised involving both socio-economical and biological factors. The latter can be either dependent on sex hormones or due to intrinsic factors. Although women have poorer outcomes and are more likely to die after a cerebrovascular event, they are still underrepresented in clinical trials and this is mirrored by the lack of sex-tailored therapies. A greater effort is needed in the future to ensure improved treatment and quality of life to both sexes.

Ischemic stroke across sexes: what is the status quo?

Stroke prevalence is expected to increase in the next decades due to the aging of the Western population. Ischemic stroke (IS) shows an age- and sex-dependent distribution in which men represent the most affected population within 65 years of age, being passed by post-menopausal women in older age groups. Furthermore, a sexual dimorphism concerning risk factors, presentation and treatment of IS has been widely recognized. In order to address these phenomena, a number of issue have been raised involving both socio-economical and biological factors. The latter can be either dependent on sex hormones or due to intrinsic factors. Although women have poorer outcomes and are more likely to die after a cerebrovascular event, they are still underrepresented in clinical trials and this is mirrored by the lack of sex-tailored therapies. A greater effort is needed in the future to ensure improved treatment and quality of life to both sexes.

Anticoagulation knowledge in patients with atrial fibrillation: An Australian survey

BACKGROUND

Atrial fibrillation (AF) is the most commonly diagnosed arrhythmia in clinical practice, and is associated with a significant medical and economic burden. Anticoagulants reduce the risk of stroke and systemic embolism by approximately two-thirds compared with no therapy. Knowledge regarding anticoagulant therapy can influence treatment outcomes in patients with AF.

OBJECTIVE

To measure the level of anticoagulation knowledge in patients with AF taking oral anticoagulants (OACs), investigate the association between patient-related factors and anticoagulation knowledge, and compare these results in patients taking warfarin and direct-acting oral anticoagulant (DOACs).

METHODS

Participants were recruited for an online survey via Facebook. Survey components included the Anticoagulation Knowledge Tool, the Perception of Anticoagulant Treatment Questionnaires (assessing treatment expectations, convenience and satisfaction), a modified Cancer Information Overload scale and the Morisky Medication Adherence Scale. Treatment groups were compared and predictors of OAC knowledge were identified.

RESULTS

Participants taking warfarin had a higher knowledge score compared with those taking DOACs (n = 386, 73% ± 13% vs 66% ± 14%, P<.001). Advancing age, type of OAC, health information overload and ease of OAC use (treatment expectation) were significant predictors of knowledge. Treatment expectation, including the belief that OAC treatment would cause bleeding side effects, varied significantly between participants taking warfarin and DOACs (P = .011).

CONCLUSION

The study identified knowledge gaps in patients taking OACs, and these deficiencies appeared to be greater in participants taking DOACs. Knowledge assessment should be integrated into patient counselling sessions to help identify and resolve knowledge deficits.

Is anticoagulating haemodialysis patients with non-valvular atrial fibrillation too risky?

There is an increasing understanding of the risks from atrial fibrillation (AF) in the current era. In patients with end-stage renal disease (ESRD) on dialysis, the prevalence of AF is significantly higher compared to the general population and those with earlier stages of CKD. Although anticoagulation of these patients may seem appropriate, there is a lack of conclusive evidence that it provides the same protection from thromboembolic complications as it does in patients not on dialysis. In addition, the increased risk of bleeding in patients requiring dialysis makes the use of anticoagulants less favourable. This article aims to discuss the problem of AF in dialysis patients, summarise the current evidence around the use of oral anticoagulants for AF in ESRD and provide some practical suggestions on management of AF in the haemodialysis population.

Interventional Echocardiography: Field of Advanced Imaging to Support Structural Heart Interventions

Multimodality imaging, particularly echocardiography, is paramount in planning and guiding structural heart disease interventions. Transesophageal echocardiography remains unique in its ability to provide real-time 2D and 3D imaging of valvular heart disease and anatomic cardiac defects, which directly impacts the strategy and outcome of these procedures. This review summarizes the role of transesophageal echocardiography in patients undergoing the most common structural heart disease interventions.

Is CHA2DS2-VASc Score Different in Patients with Non-valvular Atrial Fibrillation Suffering from Cerebral and Non-cerebral Thromboembolism?CHA2DS2-VASc Score in Thromboembolism

Background

Thromboembolic complication is directly related to CHA₂DS₂-VASc score in patients with non-valvular atrial fibrillation (NVAF). In this study we compared the CHA₂DS₂-VASc score and in-hospital mortality between NVAF patients with non-cerebral thromboembolism and those with stroke.

Methods

We retrospectively reviewed medical records of 213 patients with NVAF who experienced stroke and 115 patients with NVAF who experienced non-cerebral thromboembolism between 2010 and 2015. In all patients, CHA₂DS₂-VASc score before the event was calculated.

Results

The mean CHA₂DS₂-VASc score was similar in patients with stroke (4.52±1.66) and those with non-cerebral thromboembolism (4.29±2.02) (p=0.196). In-hospital mortality rate was similar between the groups (19% vs. 17%, p=0.756). The rates of coronary artery disease (52% vs. 38%, p=0.014), prior transient ischemic attack (16% vs. 5%, p=0.001), and prior non-cerebral thromboembolism (18% vs. 3%, p<0.001) were higher in patients with non-cerebral thromboembolism. Warfarin (55% vs. 14% p<0.001) and antiplatelet use (56% vs. 40%, p=0.004) was more common in the non-cerebral embolism group, while non-vitamin K antagonist oral anticoagulant (NOAC) use was more common in the stroke group (15% vs. 7% p=0.026).

Conclusion

The patients with stroke had similar CHA₂DS₂-VASc score and in-hospital mortality compared to patients with non-cerebral thromboembolism.

Differences among western European countries in anticoagulation management of atrial fibrillation

Due to improved implementation of guidelines, new scoring approaches to improve risk categorisation, and introduction of novel oral anticoagulants, medical management of patients with atrial fibrillation (AF) is continuously improving. The PREFER in AF registry enrolled 7,243 consecutive patients with ECG-confirmed AF in seven European countries in 2012–2013 (mean age: 71.5 ± 10.7 years; 60.1% males; mean CHA2DS 2 -VASc score: 3.4). While patient characteristics were generally homogeneous across countries, anticoagulation management showed important differences: the proportion of patients taking vitamin K antagonists (VKAs) varied between 86.0% (in France) and 71.4% (in Italy). Warfarin was used predominantly in the UK and Italy (74.9% and 62.0%, respectively), phenprocoumon in Germany (74.1%), acenocoumarol in Spain (67.3%), and fluindione in France (61.8 %). The major sites for international normalised ratio (INR) measurements were biology laboratories in France anticoagulation clinics in Italy, Spain, and the UK, and physicians’ offices or self-measurement in Germany. Temporary VKA discontinuation and bridging with other anticoagulants was frequent (at least once in the previous 12 months for 22.9% of the patients, on average; ranging from 29.7% in Germany to 14.9% in the UK). Time in therapeutic range (TTR), defined as at least two of the last three available INR values between 2.0–3.0 prior to enrolment, ranged from 70.3% in Spain to 81.4% in Germany. TTR was constantly overestimated by physicians. While the type and half-lives of VKA as well as the mode of INR surveillance differed, overall quality of anticoagulation management by TTR was relatively homogenous in AF patients across countries.

Stroke prevention in atrial fibrillation: An Asian perspective

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. In 2050, it is estimated that there will be 72 million AF patients in Asia, accounting for almost 2.9 million patients suffering from AF-associated stroke. Asian AF patients share similar risk factor profiles as non-Asians, except that more Asians have a history of previous stroke. Clinical challenges are evident in the field of stroke prevention in AF, amongst Asians. Existing stroke and bleeding risk scores have not been well-validated in Asians. Asians are prone to bleeding when treated with warfarin, and the optimal international normalised ratio (INR) for warfarin use is yet to be determined in Asians, though Asian physicians tend to keep it in a lower range (e.g. INR 1.6–2.6) for elderly patients despite limited evidence to justify this. In general, warfarin is ‘difficult’ to use in Asians due to higher risk of bleeding and higher stroke rate in Asians than in non-Asians, as shown in randomised controlled trials. Excess of bleeding was not found in Asians when novel oral anticoagulants (NOACs) were used. Besides, the superiority of NOACs to warfarin in reducing thromboembolism was maintained in Asians. Therefore NOACs are preferentially indicated in Asians in terms of both efficacy and safety. Also, some preliminary data suggest that Asian patients with AF might not be the same. Future prospective randomised trials are needed for the selection of NOACs according to different ethnic background.

Note: The review process for this manuscript was fully handled by Christian Weber, Editor in Chief.

Unanswered questions and research priorities to optimise stroke prevention in atrial fibrillation with the new oral anticoagulants

This review article discusses the following, as yet unanswered, questions and research priorities to optimise patient management and stroke prevention in atrial fibrillation with the new direct oral anticoagulants (NOACs): 1. In patients prescribed a NOAC, can the anticoagulant effects or plasma concentrations of the NOACs be measured rapidly and reliably and, if so, can “cut-off points” between which anticoagulation is therapeutic (i.e. the “therapeutic range”) be defined? 2. In patients who are taking a NOAC and bleeding (e.g. intracerebral haemorrhage), can the anticoagulant effects of the direct NOACs be reversed rapidly and, if so, can NOAC-associated bleeding and complications be minimised and patient outcome improved? 3. In patients taking a NOAC who experience an acute ischaemic stroke, to what degree of anticoagulation or plasma concentration of NOAC, if any, can thrombolysis be administered safely and effectively? 4. In patients with a recent cardioembolic ischaemic stroke, what is the optimal time to start (or re-start) anticoagulation with a NOAC (or warfarin)? 5. In anticoagulated patients who experience an intracranial haemorrhage, can anticoagulation with a NOAC be re-started safely and effectively, and if so when? 6. Are the NOACs effective and safe in multimorbid geriatric people (who commonly have atrial fibrillation and are at high risk of stroke but also bleeding)? 7. Can dose-adjusted NOAC therapy augment the established safety and efficacy of fixed-dose unmonitored NOAC therapy? 8. Is there a dose or dosing regimen for each NOAC that is as effective and safe as adjusted-dose warfarin for patients with atrial fibrillation who have mechanical prosthetic heart valves? 9. What is the long-term safety of the NOACs?

Non-vitamin K antagonist oral anticoagulants for heart diseases

Non-vitamin K antagonist oral anticoagulants (NОАСs) are highly effective drugs that prevent venous thrombosis and stroke in atrial fibrillation. Their use has difficulties that are associated with the need for laboratory control and with the influence of many factors on the activity of these medications. The emerged direct oral anticoagulants have some advantages over NOACs. Nevertheless, there are a number of pathological conditions, in which NOACs remain first-line drugs. These include prosthetic mechanical heart valves, a glomerular filtration rate less than 60 mL/min/1.73 m2, and left atrial thrombus.

Cost-Effectiveness of Edoxaban vs. Warfarin in Patients with Atrial Fibrillation Based on Results of the ENGAGE AF - TIMI 48 Trial: Taiwanese Perspective

BACKGROUND

Novel anticoagulants, such as factor Xa inhibitors, have entered clinical practice as alternatives to warfarin for the prevention of stroke and systemic embolic event (SEE) in patients with atrial fibrillation (AF). It is not known whether edoxaban, the fourth-to-market factor Xa inhibitor approved for this indication, will be cost-effective in Taiwan, where the cost of warfarin monitoring is prohibitive.

METHODS

A Markov model projecting lifetime results of edoxaban 60 mg/30 mg dose-reduced versus warfarin in patients with nonvalvular AF, based on the ENGAGE AF - TIMI 48 trial, found edoxaban to be of high value relative to warfarin, from the perspective of the US health care system. We applied Taiwan-specific cost inputs to this model structure to assess the relative cost-effectiveness of edoxaban versus warfarin from the perspective of the Taiwanese health care system. Event rates and hazard ratios from the ENGAGE AF - TIMI 48 East Asian subpopulation were explored in sensitivity analyses.

RESULTS

Edoxaban was found to be highly cost-effective compared with warfarin, based on guidelines proposed by the World Health Organization (WHO), with a base case incremental cost-effectiveness ratio of $12,902 per quality-adjusted life year gained. These results were robust to variation of key model parameters, including assumptions regarding the cost and quality-of-life impact of stroke and bleeding events, and assuming East Asian-specific (as opposed to full-trial-population) rates for combinations of ischemic stroke, SEE, and major bleeding.

CONCLUSIONS

Despite its higher acquisition cost, edoxaban is an economically attractive alternative to warfarin for the prevention of stroke and SEE in patients with AF in Taiwan.

Sex-Related Differences in the Clinical Events of Patients With Atrial Fibrillation - The Fushimi AF Registry

BACKGROUND

Female sex is considered a risk factor for thromboembolism in patients with atrial fibrillation (AF), and is included in the risk stratification scheme, CHA₂DS₂-VASc score. The purpose of the present study was to investigate the clinical outcomes of female Japanese AF patients.Methods and Results:The Fushimi AF Registry is a community-based prospective survey of the AF patients in Fushimi-ku, Kyoto. Follow-up data were available for 3,878 patients. Female AF patients (n=1,551, 40.0%) were older (77.0 vs. 71.4 years; P<0.001) than male patients (n=2,327, 60.0%). Female patients were more likely to have heart failure (31.1% vs. 23.7%; P<0.001). Previous stroke incidence (19.2% vs. 21.4%; P=0.083) was comparable between male and female patients. During the median follow-up period of 1,102 days, Cox regression analysis demonstrated that female sex was not independently associated with a risk of stroke or systemic embolism (adjusted hazard ratio [HR] 0.74; 95% confidence interval [CI]: 0.54-1.00, P=0.051). However, female sex showed an association with a lower risk of intracranial hemorrhage (adjusted HR 0.54; 95% CI: 0.30-0.95, P=0.032) and all-cause death (adjusted HR 0.56; 95% CI: 0.46-0.68, P<0.001).

CONCLUSIONS

We demonstrated that female sex is not independently associated with an increased risk of thromboembolism, but is associated with a decreased risk of intracranial hemorrhage and all-cause death in Japanese AF patients enrolled in the Fushimi AF Registry.

Familial clustering of atrial fibrillation and comparative longitudinal outcomes of familial and non-familial atrial fibrillation

Several studies have suggested that family history of atrial fibrillation (AF) is an important risk factor for AF, with several specific genetic regions now implicated through Genome Wide Association Studies. In addition, familial AF is associated with earlier age of onset and affects patients with fewer comorbid conditions than their non-familial counterparts. While those with familial AF have worse symptoms, all-cause mortality and risk of thromboembolic complications are similar among familial and non-familial AF patients.

Predictive Role of Coagulation, Fibrinolytic, and Endothelial Markers in Patients with Atrial Fibrillation, Stroke, and Thromboembolism: A Meta-Analysis, Meta-Regression, and Systematic Review

Background

The pathophysiological mechanism associated with the higher prothrombotic tendency in atrial fibrillation (AF) is complex and multifactorial. However, the role of prothrombotic markers in AF remains inconclusive.

Material/Methods

We conducted a meta-analysis of observational studies evaluating the association of coagulation activation, fibrinolytic, and endothelial function with occurrence of AF and clinical adverse events. A comprehensive subgroup analysis and meta-regression was performed to explore potential sources of heterogeneity.

Results

A literature search of major databases retrieved 1703 studies. After screening, a total of 71 studies were identified. Pooled analysis showed the association of coagulation markers (D-dimer (weighted mean difference (WMD)=197.67 and p<0.001), fibrinogen (WMD=0.43 and p<0.001), prothrombin fragment 1–2 (WMD=0.53 and p<0.001), antithrombin III (WMD=23.90 and p=0.004), thrombin-antithrombin (WMD=5.47 and p=0.004)); fibrinolytic markers (tissue-type plasminogen activator (t-PA) (WMD=2.13 and p<0.001), plasminogen activator inhibitor (WMD=11.44 and p<0.001), fibrinopeptide-A (WMD=4.13 and p=0.01)); and endothelial markers (von Willebrand factor (WMD=27.01 and p<0.001) and soluble thrombomodulin (WMD=3.92 and p<0.001)) with AF.

Conclusions

The levels of coagulation, fibrinolytic, and endothelial markers have been reported to be significantly higher in AF patients than in SR patients.

Left atrial appendage occlusion: A better alternative to anticoagulation?

Non-valvular atrial fibrillation is associated with a significantly increased risk of embolic stroke due to blood clot forming predominantly in the left atrial appendage (LAA). Preventive measures to avoid embolic events are permanent administration of anticoagulants or surgical closure of the LAA. Various clinical trials provide evidence about safety, effectiveness and therapeutic success of LAA occlusion using various cardiac occluder devices. The use of such implants for interventional closure of the LAA is likely to become a valuable alternative for stroke prevention, especially in patients with contraindication for oral anticoagulation as safety, clinical benefit and cost-effectiveness of LAA occlusion has recently been demonstrated.

CHA2DS2-VASc score in the prediction of ischemic bowel disease among patients with atrial fibrillation: Insights from a nationwide cohort

PURPOSE

This study aimed to evaluate the predictive role of CHA₂DS₂-VASc score specifically for the development of ischemic bowel disease (IBD) among atrial fibrillation (AF) patients.

METHODS

Using a nationwide dataset, an AF cohort was established. The study participants were followed up from the index date until they withdrew from the health insurance system, the occurrence of IBD or until the end of 2011. The hazard ratios (HRs) and 95% confidence intervals (CIs) were examined by Cox models to present the subsequent risk of IBD among AF patients by CHA₂DS₂-VASc score. The area under the receiver operating characteristic (ROC) curve was used to assess the predictive power of CHA₂DS₂-VASc score for IBD development among AF patients.

RESULTS

The cumulative incidence of IBD was higher for AF patients with a CHA₂DS₂-VASc score≥2 than those with a CHA₂DS₂-VASc score<2 by 2.30% (p<0.001) at the end of follow-up. After adjustment for hyperlipidemia, chronic obstructive pulmonary disease, and chronic kidney disease, the AF patients with a CHA₂DS₂-VASc score≥2 had a 3.35 times higher risk for IBD development compared to those with a CHA₂DS₂-VASc score<2 [adjusted HR (aHR)=3.35, 95% CI=2.71-4.13]. Among AF patients, the C-statistic of the CHA₂DS₂-VASc score as a predictor of IBD was 0.56 (95% CI=0.55-0.57).

CONCLUSIONS

In conclusion, the study is​ the first to investigate the predictive role of CHA₂DS₂-VASc score specifically for IBD development among AF patients. However, the predictive power was relatively low; further studies are necessary to confirm our findings.