Antithrombotic Therapy for Atrial Fibrillation

The global Edoxaban Treatment in routine cliNical prActice (ETNA) noninterventional study program: rationale and design

Background

Randomized controlled trials showed the nonvitamin K oral anticoagulant (NOAC) edoxaban was effective and safe for stroke and systemic embolism prevention in nonvalvular atrial fibrillation (AF) and for the prevention and treatment of venous thromboembolism (VTE; including pulmonary embolism and deep vein thrombosis). Additional research is needed to evaluate the effects of edoxaban in routine clinical practice. Therefore, the Edoxaban Treatment in routine cliNical prActice (ETNA) program is being conducted to provide routine clinical care data on characteristics and outcomes in patients with AF or VTE receiving edoxaban.

Methods

The Global ETNA program integrates prospectively collected data from edoxaban patients in regional ETNA noninterventional studies across Europe, Japan, and East and Southeast Asia into indication‐specific databases for AF and VTE. Targeted enrollment is >31 000 patients (AF >26 000; VTE >4500), with a follow‐up of 2 years for AF and 1 year for VTE. Data integration will be possible using consistent terminology, parameter definitions, and data collection across the regional noninterventional studies. Safety and effectiveness data will be assessed. Crude rates of outcomes including bleeding and thromboembolic events will be reported.

Results

Globally, enrollment began in early 2015 and is ongoing.

Conclusions

Global ETNA will generate the largest integrated prospective repository of routine clinical care data for a single NOAC in patients with AF or VTE. It will provide important information on the safety of edoxaban in routine clinical care and gather further information on its effectiveness.

Should We Judge Stroke Risk by Static or Dynamic Risk Scores? A Focus on the Dynamic Nature of Stroke and Bleeding Risks in Patients With Atrial Fibrillation

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia and a major risk factor for stroke. The number of patients with AF is predicted to increase in the next few decades. AF has also negative impact on quality of life as well as it significantly increases the risk of cardiovascular disease and overall mortality. Because the stroke is a pivotal outcome of AF, its prevention with the use of anticoagulation therapy constitutes an important component of AF management. The decision on oral anticoagulants' prescription should be based on appropriate risk stratification to allow for comprehensive assessment of benefit/hazard ratio of stroke and bleeding along with patients' preference. Several risk scores for stroke and bleeding as well as for stroke and systemic embolism have been developed, mainly in patients on vitamin K antagonists. AF guidelines stress the need for repetitive evaluation of thromboembolic and bleeding risks to tailor optimal AF management. Indeed, risk is not a static "one off" process and it should be adjusted for dynamic nature of risk factors. However, most risk scores are calculated according to baseline characteristics of patients, but the older the patients get, the more comorbidities they acquire, which influences stroke risk significantly. Hence, the default management of every patient with AF should include a regular reassessment of stroke and bleeding risk factors.

A drug safety evaluation of apixaban for the treatment of atrial fibrillation, acute coronary syndrome, and percutaneous coronary intervention

Introduction: The non-vitamin K antagonist oral anticoagulants (NOACs) are changing the landscape for stroke prevention in atrial fibrillation (AF) and prevention or treatment of venous thromboembolism (VTE). In patients with AF and concomitant acute coronary syndrome (ACS), the treatment regimen of combined NOACs and P2Y₁₂ inhibitors is gaining popularity.Areas covered: We conducted a review of safety evaluation and effectiveness of apixaban for AF and ACS treatment, both alone and in combination with different antiplatelet treatment regimens. The aim was to provide an overview of apixaban including mechanism of action, indications, adverse events and tolerability.Expert opinion: Apixaban is recommended as a safe, well tolerated and effective oral anticoagulant for reducing the risk of ischemic events among AF patients. It is of value in prevention and treatment of VTE and pulmonary embolism. Comparing to VKA, apixaban was superior in preventing stroke or systemic embolism with lower major bleeding events among AF patients. When combined with dual antiplatelet therapy apixaban may cause dose-related increase in bleeding which reduces the benefit of this treatment regimen among ACS patients but without AF. In those with ACS and concomitant AF, the combination of apixaban with P2Y₁₂ inhibitor appears to be safe and effective.

Consensus Clinical Decision-Making Factors Driving Anticoagulation in Atrial Fibrillation

Guideline-recommended anticoagulation is frequently omitted in high-risk patients with atrial fibrillation (AF) for reasons not fully understood, which may result in suboptimal care. A nationally representative, expert group of physicians (cardiology, neurology, and general medicine), and clinical pharmacists participated in a consensus-seeking, modified Delphi method to identify key clinical decision-making factors driving anticoagulant prescribing in real-world AF patients. Representing >2,500 anticoagulation-related patient encounters per month, 27 of 30 participants completed the study (90% overall response rate). In Round-1, experts rated their level of agreement with factors and suggested modifications or additional factors. Of 66 factors entering Round-1, 21 met and 4 partially met consensus, 41 did not meet consensus, and 7 were newly suggested. Of 32 factors advanced for scoring in Round-2, 16 met consensus criteria. In Round-3, experts were given the option to rescue up to 2 of the 16 nonconsensus factors from Round-2. Including a concomitant need for dual antiplatelet therapy, no factor was successfully rescued into consensus. The most important factors related to risk of infarction rather than bleeding risk or other patient-specific considerations. Among factors not independently addressed in current guidelines, these included baseline hematologic indicators of potential bleeding risk, previous bleeding episodes by specific type, other risk factors for bleeding, and adherence. In conclusion, when determining anticoagulation strategies in AF, there is a need for further research on the clinical implications of these emerging factors as well as the reasons behind divergent opinions toward nonconsensus factors.

Impact of a pharmacist-led education and follow-up service on anticoagulation control and safety outcomes at a tertiary hospital in China: a randomised controlled trial

OBJECTIVES

This study was designed to evaluate the impact of a pharmacist-led anticoagulation service on international normalised ratio (INR) control and other outcomes among patients receiving warfarin therapy at a tertiary hospital in Zhuhai, China.

METHODS

In this randomised controlled trial, adult patients who were newly initiated on warfarin with intended treatment duration of at least 3 months were recruited. Participants were randomly allocated to receive the pharmacist-led education and follow-up service (PEFS) or usual care (UC). Anticoagulation control was calculated as the proportions of time within the target INR range (TTR) and time within the expanded target range (TER).

KEY FINDINGS

A total of 152 participants (77 in the PEFS group and 75 in the UC group) were included. Within 180 days after hospital discharge, the PEFS group spent more TER than the UC group (54.4% versus 42.0%; P = 0.024), whereas the difference in TTR did not reach statistical significance (35.9% versus 29.5%; P = 0.203). No major bleeding events were observed, and the cumulative incidences of major thromboembolic events (6.5% versus 9.3%) and mortality (1.3% versus 1.3%) were similar between the two groups (P> 0.05). At 30 days postdischarge, the PEFS group had better warfarin knowledge by answering 57.5% of questions correctly, compared with the UC group (43.0%) (P = 0.003).

CONCLUSIONS

The PEFS markedly enhanced anticoagulation control and warfarin knowledge but there was room for improvement. The expansion of pharmacists' clinical role and the development of more effective education and follow-up strategies are warranted to optimise anticoagulation management services in China.

Use of simplified HAS-BLED score in patients with atrial fibrillation receiving warfarin

BACKGROUND

Oral anticoagulant drugs are proven to prevent thromboembolism in patients with atrial fibrillation (AF). To date, HAS-BLED score is used to assess bleeding risk. This study was conducted to compare simplified HAS-BLED (sHAS-BLED) with conventional HAS-BLED (cHAS-BLED) scores.

METHODS

This retrospective study recruited patients with AF receiving warfarin among July 2013 to December 2018 in Central Chest Institute of Thailand. The cHAS-BLED score used the time in therapeutic range less than 70% as labile INR, whereas sHAS-BLED score used SAMe-TT2R2 score of 3 or more as a substitute for labile INR. A paired Student's t test was used to compare sHAS-BLED and cHAS-BLED. The Pearson's correlation was used to assess the correlation of sHAS-BLED to cHAS-BLED scores. The Bland-Altman plot was used to confirm the agreement of individual sHAS-BLED to cHAS-BLED score.

RESULTS

A total of 126 AF patients were enrolled. The average age, SAMe-TT2R2 score, and cHAS-BLED score were 70.52 ± 10.37 years, 3.53 ± 1.03, and 2.03 ± 0.95, respectively. The sHAS-BLED score was not statistically significantly different compared with cHAS-BLED score (P = .08). The sHAS-BLED and cHAS-BLED scores had a very strong correlation with a correlation coefficient of .86 (P < .01). The Bland-Altman plot was performed to confirm the agreement of individual sHAS-BLED to cHAS-BLED scores.

CONCLUSIONS

The sHAS-BLED was not statistically significantly different compared with cHAS-BLED and can be used in clinical practice. However, larger clinical trial will be needed to prove whether sHAS-BLED can predict bleeding risk in the future.

Clinical Effectiveness of Direct Oral Anticoagulants vs Warfarin in Older Patients With Atrial Fibrillation and Ischemic Stroke: Findings From the Patient-Centered Research Into Outcomes Stroke Patients Prefer and Effectiveness Research (PROSPER) Study

Importance

Current guidelines recommend direct oral anticoagulants (DOACs) over warfarin for stroke prevention in patients with atrial fibrillation (AF) who are at high risk. Despite demonstrated efficacy in clinical trials, real-world data of DOACs vs warfarin for secondary prevention in patients with ischemic stroke are largely based on administrative claims or have not focused on patient-centered outcomes.

Objective

To examine the clinical effectiveness of DOACs (dabigatran, rivaroxaban, or apixaban) vs warfarin after ischemic stroke in patients with AF.

Design, Setting, and Participants

This cohort study included patients who were 65 years or older, had AF, were anticoagulation naive, and were discharged from 1041 Get With The Guidelines-Stroke-associated hospitals for acute ischemic stroke between October 2011 and December 2014. Data were linked to Medicare claims for long-term outcomes (up to December 2015). Analyses were completed in July 2018.

Exposures

DOACs vs warfarin prescription at discharge.

Main Outcomes and Measures

The primary outcomes were home time, a patient-centered measure defined as the total number of days free from death and institutional care after discharge, and major adverse cardiovascular events. A propensity score-overlap weighting method was used to account for differences in observed characteristics between groups.

Results

Of 11 662 survivors of acute ischemic stroke (median [interquartile range] age, 80 [74-86] years), 4041 (34.7%) were discharged with DOACs and 7621 with warfarin. Except for National Institutes of Health Stroke Scale scores (median [interquartile range], 4 [1-9] vs 5 [2-11]), baseline characteristics were similar between groups. Patients discharged with DOACs (vs warfarin) had more days at home (mean [SD], 287.2 [114.7] vs 263.0 [127.3] days; adjusted difference, 15.6 [99% CI, 9.0-22.1] days) during the first year postdischarge and were less likely to experience major adverse cardiovascular events (adjusted hazard ratio [aHR], 0.89 [99% CI, 0.83-0.96]). Also, in patients receiving DOACs, there were fewer deaths (aHR, 0.88 [95% CI, 0.82-0.95]; P < .001), all-cause readmissions (aHR, 0.93 [95% CI, 0.88-0.97]; P = .003), cardiovascular readmissions (aHR, 0.92 [95% CI, 0.86-0.99]; P = .02), hemorrhagic strokes (aHR, 0.69 [95% CI, 0.50-0.95]; P = .02), and hospitalizations with bleeding (aHR, 0.89 [95% CI, 0.81-0.97]; P = .009) but a higher risk of gastrointestinal bleeding (aHR, 1.14 [95% CI, 1.01-1.30]; P = .03).

Conclusions and Relevance

In patients with acute ischemic stroke and AF, DOAC use at discharge was associated with better long-term outcomes relative to warfarin.

First evidence for a pharmacist-led anticoagulant clinic in a medicare part A long term care environment

Anticoagulation risks in older adult, long-term care patients are known to be high, especially in those with frequent transitions between care environments. Introduction of collaborative practice agreements (CPA) in specific settings is encouraged in the United States and has provided an additional option for the care of medically challenging patients. The aim of this study was to investigate the time in therapeutic range (TTR) in a Medicare Part A sponsored long-term care environment managed by pharmacists through a collaborative practice agreement in South-Central Appalachia. A retrospective review of all warfarin patient admissions from a large long-term care pharmacy's anticoagulant clinic was conducted for residents over an 18-month period. For all patients (n = 104), the overall TTR was 46.7% (INR 43% in range). Average management duration was 19.5 days per patient. Further studies are required to optimize CPA and transition strategies for complex, advanced age warfarin patients.

Atrial Fibrillation and Stroke. A Review on the Use of Vitamin K Antagonists and Novel Oral Anticoagulants

Atrial fibrillation (AF) is the most common arrhythmia, ranging from 0.1% in patients <55 years to >9% in octogenarian patients. One important issue is represented by the 5-fold increased ischemic stroke risk in AF patients. Hence, the role of anticoagulation is central. Until a few years ago, vitamin K antagonists (VKAs) and low molecular weight heparin represented the only option to prevent thromboembolisms, though with risks. Novel oral anticoagulants (NOACs) have radically changed the management of AF patients, improving both life expectancy and life quality. This review aims to summarize the most recent literature on the use of VKAs and NOACs in AF, in light of the new findings.

Meta-Analysis of Oral Anticoagulant Monotherapy as an Antithrombotic Strategy in Patients With Stable Coronary Artery Disease and Nonvalvular Atrial Fibrillation

Guidelines recommend oral anticoagulant (OAC) monotherapy without antiplatelet therapy (APT) in patients with nonvalvular atrial fibrillation (AF) with stable coronary artery disease (CAD) of >1 year after myocardial infarction or percutaneous coronary intervention. More evidences are required for the safety and efficacy of OAC monotherapy compared with OAC plus APT. PubMed, EMBASE, and Cochrane Database of Systematic Reviews were systematically searched up to February 2019. Nonrandomized studies and randomized clinical trials comparing OAC monotherapy with OAC plus single APT (SAPT) for patients with stable CAD and nonvalvular AF. The primary end point was major adverse cardiovascular events (composite of ischemic or thrombotic events) and secondary outcomes included major bleeding, stroke, all-cause death, and net adverse events (composite of ischemic, thrombotic, or bleeding events). From 6 trials, 8,855 patients were included. There was no significant difference in major adverse cardiovascular event in patients with AF treated using OAC plus SAPT compared with those treated with OAC monotherapy (hazard ratio [HR] 1.09; 95% confidence interval [CI] 0.92 to 1.29). OAC plus SAPT was associated with a significantly higher risk of major bleeding compared with OAC monotherapy (HR 1.61; 95% CI 1.38 to 1.87), as well as in terms of net adverse event (HR 1.21; 95% CI 1.02 to 1.43). There were no significant differences in rates of stroke and all-cause death. In conclusion, in this meta-analysis, OAC monotherapy and OAC plus SAPT treatment showed similar effectiveness, but OAC monotherapy was significantly associated with a lower risk of bleeding compared with OAC plus SAPT in patients with nonvalvular AF and stable CAD.

Association between epicardial adipose tissue and embolic stroke after catheter ablation of atrial fibrillation

INTRODUCTION

Risk factors of embolic stroke (ES) after atrial fibrillation (AF) ablation have not been fully elucidated especially among the Asian subjects, particularly regarding epicardial adipose tissue (EAT) in cardiac imaging. We aimed to assess the incidence of ES during a long-term follow-up period after AF ablation and to identify the risk factors associated with postablation ES, specifically focusing on EAT.

METHODS AND RESULTS

We enrolled patients who experienced postablation ES and control subjects from a consortium of AF ablation registries from three institutes in Korea. EAT was assessed using multislice computed tomography before AF ablation. A total of 3464 patients who underwent AF ablation were recruited and followed-up. During a follow-up of 47.2 ± 36.4 months, ES occurred in 47 patients (1.36%) with a CHA₂ DS₂ -VASc score of 1.48 ± 1.39 and the overall annual incidence of ES was 0.34%. Compared with the control group (n = 190), the ES group showed significantly higher prior thromboembolism (TE) and AF recurrence rates, larger left atrium size, lower creatinine clearance rate (CCr), and greater total and peri-atrial EAT volume. Multivariate regression analysis demonstrated larger peri-atrial EAT volume (hazards ratio, 1.065; 95% confidence interval, 1.005-1.128), in addition to a prior history of TE and lower CCr, was independently associated with postablation ES. When a cut-off value of peri-atrial EAT volume of ≥20.15 mL was applied, patients with smaller peri-atrial EAT volume showed significantly higher ES-free survival.

CONCLUSION

Larger peri-atrial EAT volume, in addition to prior TE and lower CCr, was independently associated with postablation ES regardless of AF recurrence and CHA₂ DS₂ -VASc score. (ClinicalTrials.gov number, NCT03479073).

An artificial intelligence-enabled ECG algorithm for the identification of patients with atrial fibrillation during sinus rhythm: a retrospective analysis of outcome prediction

BACKGROUND

Atrial fibrillation is frequently asymptomatic and thus underdetected but is associated with stroke, heart failure, and death. Existing screening methods require prolonged monitoring and are limited by cost and low yield. We aimed to develop a rapid, inexpensive, point-of-care means of identifying patients with atrial fibrillation using machine learning.

METHODS

We developed an artificial intelligence (AI)-enabled electrocardiograph (ECG) using a convolutional neural network to detect the electrocardiographic signature of atrial fibrillation present during normal sinus rhythm using standard 10-second, 12-lead ECGs. We included all patients aged 18 years or older with at least one digital, normal sinus rhythm, standard 10-second, 12-lead ECG acquired in the supine position at the Mayo Clinic ECG laboratory between Dec 31, 1993, and July 21, 2017, with rhythm labels validated by trained personnel under cardiologist supervision. We classified patients with at least one ECG with a rhythm of atrial fibrillation or atrial flutter as positive for atrial fibrillation. We allocated ECGs to the training, internal validation, and testing datasets in a 7:1:2 ratio. We calculated the area under the curve (AUC) of the receiver operatoring characteristic curve for the internal validation dataset to select a probability threshold, which we applied to the testing dataset. We evaluated model performance on the testing dataset by calculating the AUC and the accuracy, sensitivity, specificity, and F1 score with two-sided 95% CIs.

FINDINGS

We included 180 922 patients with 649 931 normal sinus rhythm ECGs for analysis: 454 789 ECGs recorded from 126 526 patients in the training dataset, 64 340 ECGs from 18 116 patients in the internal validation dataset, and 130 802 ECGs from 36 280 patients in the testing dataset. 3051 (8·4%) patients in the testing dataset had verified atrial fibrillation before the normal sinus rhythm ECG tested by the model. A single AI-enabled ECG identified atrial fibrillation with an AUC of 0·87 (95% CI 0·86-0·88), sensitivity of 79·0% (77·5-80·4), specificity of 79·5% (79·0-79·9), F1 score of 39·2% (38·1-40·3), and overall accuracy of 79·4% (79·0-79·9). Including all ECGs acquired during the first month of each patient's window of interest (ie, the study start date or 31 days before the first recorded atrial fibrillation ECG) increased the AUC to 0·90 (0·90-0·91), sensitivity to 82·3% (80·9-83·6), specificity to 83·4% (83·0-83·8), F1 score to 45·4% (44·2-46·5), and overall accuracy to 83·3% (83·0-83·7).

INTERPRETATION

An AI-enabled ECG acquired during normal sinus rhythm permits identification at point of care of individuals with atrial fibrillation.

FUNDING

None.

The effect of heparin infusion intensity on outcomes for bridging hospitalized patients with atrial fibrillation

Background

Perioperative bridging in atrial fibrillation (AF) is associated with low thromboembolic rates but high bleeding rates. Recent guidance cautions the practice of bridging except in high risk patients. However, the practice of bridging varies widely and little data exist regarding appropriate anticoagulation intensity when using intravenous unfractionated heparin (UFH).

Hypothesis

To determine if high intensity UFH infusion regimens are associated with increased bleeding rates compared to low intensity regimens for bridging patients with AF.

Methods

We conducted a single center retrospective cohort study of admitted patients with non‐valvular AF receiving UFH for ≥24 hours. UFH intensities were chosen at the providers' discretion. The primary endpoint was the rate of bleeding defined by the International Society on Thrombosis and Hemostasis during UFH infusion or within 24 hours of discontinuation. The secondary endpoint was a composite of cardiovascular events, arterial thromboembolism, venous thromboembolism, myocardial infarctions and death during UFH infusion.

Results

A total of 497 patients were included in this analysis. Warfarin was used in 82.1% and direct acting oral anticoagulants in 14.1% of patients. The rate of any bleed was higher among high intensity compared to low intensity UFH regimens (10.5% vs 4.9%, odds ratio = 2.29, 95% confidence interval = 1.07‐4.90). Major bleeding was significantly higher among high intensity compared to low intensity UFH regimens. There was no difference in composite thrombotic events or death.

Conclusions

Low intensity UFH infusions, targeting lower anticoagulation targets, were associated with decreased bleeding rates without a signal of increased thromboembolic events in hospitalized AF patients.

Mobile Photoplethysmographic Technology to Detect Atrial Fibrillation

BACKGROUND

Low detection and nonadherence are major problems in current management approaches for patients with suspected atrial fibrillation (AF). Mobile health devices may enable earlier AF detection and improved AF management.

OBJECTIVES

This study sought to investigate the effectiveness of AF screening in a large population-based cohort using smart device-based photoplethysmography (PPG) technology, combined with a clinical care AF management pathway using a mobile health approach.

METHODS

AF screening was performed with smart devices using PPG technology, which were made available for the population ≥18 years of age across China. Monitoring for at least 14 days with a wristband (Honor Band 4) or wristwatch (Huawei Watch GT, Honor Watch, Huawei Technologies Co., Ltd., Shenzhen, China) was allowed. The patients with "possible AF" episodes using the PPG algorithm were further confirmed by health providers among the MAFA (mobile AF app) Telecare center and network hospitals, with clinical evaluation, electrocardiogram, or 24-h Holter monitoring.

RESULTS

There were 246,541 individuals who downloaded the PPG screening app, and 187,912 individuals used smart devices to monitor their pulse rhythm between October 26, 2018, and May 20, 2019. Among those with PPG monitoring (mean age 35 years, 86.7% male), 424 (of 187,912, 0.23%) (mean age 54 years, 87.0% male) received a "suspected AF" notification. Of those effectively followed up, 227 individuals (of 262, 87.0%) were confirmed as having AF, with the positive predictive value of PPG signals being 91.6% (95% confidential interval [CI]: 91.5% to 91.8%). Both suspected AF and identified AF markedly increased with age (p for trend <0.001), and individuals in Northeast China had the highest proportion of detected AF of 0.28% (95% CI: 0.20% to 0.39%). Of the individuals with identified AF, 216 (of 227, 95.1%) subsequently entered a program of integrated AF management using a mobile AF application; approximately 80% of high-risk patients were successfully anticoagulated.

CONCLUSIONS

Based on the present study, continuous home monitoring with smart device-based PPG technology could be a feasible approach for AF screening. This would help efforts at screening and detection of AF, as well as early interventions to reduce stroke and other AF-related complications. (Mobile Health [mHealth] Technology for Improved Screening, Patient Involvement and Optimizing Integrated Care in Atrial Fibrillation [MAFA II]; ChiCTR-OOC-17014138).

Current status of oral anticoagulant reversal strategies: a review

Utilization of direct oral anticoagulants (DOAC) have steadily increased since their approval and are now recommended over warfarin for both stroke prevention in nonvalvular atrial fibrillation and treatment of venous thromboembolism (VTE). With increased DOAC use, the number of major bleeding events requiring medical intervention will continue to rise. Until 2015, warfarin maintained an advantage as the only oral anticoagulant with a specific reversal agent. Since then, idarucizumab has been approved for dabigatran reversal and recently, andexanet alfa was granted approval for the reversal of apixaban or rivaroxaban in patients with life-threatening or uncontrolled bleeding events. Due to the manufacturing practices required to yield these reversal therapies, they are available at high cost to hospital systems and as a result, have been met with resistance. Data exists describing both prothrombin complex concentrates (PCC) and andexanet alfa for DOAC reversal, however, without head-to-head comparison. Until future studies are available, current literature must be critically evaluated to aid in the clinical decision-making process of how to treat patients with life-threatening DOAC-related bleeding.

From WOEST to AUGUSTUS: a review of safety and efficacy of triple versus dual antithrombotic regimens in patients with atrial fibrillation requiring percutaneous coronary intervention for acute coronary syndrome

For patients with atrial fibrillation with concomitant acute coronary syndrome (ACS) requiring percutaneous coronary intervention (PCI), the increased risk of bleeding associated with the use triple therapy is well established. However, there is question whether it is a necessary risk for patients to prevent stroke and stent thrombosis. The purpose of this article is to highlight the findings of prior studies evaluating the comparative safety and efficacy of dual and triple antithrombotic regimens in the subgroup of atrial fibrillation patients requiring PCI for ACS. Trials that evaluated dual versus triple antithrombotic therapy demonstrated post-PCI treatment with a P2Y12 inhibitor alone was safer than aspirin plus a P2Y12 inhibitor in patients also taking an anticoagulant for atrial fibrillation. Data regarding ischemic outcomes have not suggested harm with the omission of aspirin, but these studies have not been powered to assess efficacy outcomes, especially in ACS patients. These studies also demonstrate a significant reduction in bleeding events when aspirin is excluded from the post-PCI regimen in the ACS subgroup of atrial fibrillation patients. Further studies, with added focus on the ACS subgroup, are needed to potentially confirm that dual therapy may be as efficacious as triple therapy in ACS patients with atrial fibrillation.

Prise en charge hémostatique des hémorragies cérébrales sous anticoagulants oraux

L’hématome intracrânien spontané a un pronostic clinique sévère. Le devenir des patients dépend de l’efficacité de la prise en charge initiale. L’importance du saignement, le volume de l’hématome et son évolution sont les facteurs principaux qui contrôlent mortalité et morbidité. Les traitements anticoagulants oraux, antivitamines K (AVK) et anticoagulants oraux directs (AOD), favorisent l’expansion de l’hématome. La correction rapide de l’hémostase permet le contrôle partiel de l’hématome. Alors que la réversion des AVK par les concentrés de complexe prothrombinique (CCP) a fait l’objet de recommandations bien diffusées, l’attitude thérapeutique reste peu codifiée avec les AOD, alliant l’utilisation de l’idarucizumab pour le dabigatran et des CCP pour les anti-Xa qui n’ont, pour l’instant, pas d’antidote.

Factors That Affect Time to Switch From Warfarin to a Direct Oral Anticoagulant After Change in the Reimbursement Criteria in Patients With Atrial Fibrillation

BACKGROUND

Anticoagulation therapy is recommended for stroke prevention in high-risk patients with atrial fibrillation (AF). This study aimed to estimate the time to switch from warfarin to a direct oral anticoagulant (DOAC) and identify the factors associated with it.

METHODS

By using claims data, we studied 7111 warfarin-using patients with nonvalvular AF who were aged ≥65 years. The Kaplan-Meier analysis was performed to estimate the time to switch from warfarin to a DOAC, and Cox proportional hazard regression analysis was used to estimate the influencing factors.

RESULTS

Approximately one-third of the patients (2403, 33.8%) switched from warfarin to a DOAC during the study period. Female sex, aged between 75 and 79 years, having a Medical Aid or Patriots and Veterans Insurance, hypertension, and history of prior stroke, and transient ischemic attack or thromboembolism (prior stroke/TIA/TE) were associated with a significantly shorter time to switch. The odds of switching to a DOAC were increased by approximately 1.2-fold in the women and 1.4-fold in the patients with prior stroke/TIA/TE.

CONCLUSIONS

Approximately one-third of the warfarin-using patients switched from warfarin to a DOAC within 6 months after the change in the DOAC reimbursement criteria. In the Cox proportional hazard regression analysis, the factors that affected anticoagulant switching from warfarin to a DOAC were female sex and history of prior stroke/TIA/TE.

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.

Benefits and Harms of Oral Anticoagulant Therapy in Chronic Kidney Disease: A Systematic Review and Meta-analysis

BACKGROUND

Effects of oral anticoagulation in chronic kidney disease (CKD) are uncertain.

PURPOSE

To evaluate the benefits and harms of vitamin K antagonists (VKAs) and non-vitamin K oral anticoagulants (NOACs) in adults with CKD stages 3 to 5, including those with dialysis-dependent end-stage kidney disease (ESKD).

DATA SOURCES

English-language searches of MEDLINE, EMBASE, and Cochrane databases (inception to February 2019); review bibliographies; and ClinicalTrials.gov (25 February 2019).

STUDY SELECTION

Randomized controlled trials evaluating VKAs or NOACs for any indication in patients with CKD that reported efficacy or bleeding outcomes.

DATA EXTRACTION

Two authors independently extracted data, assessed risk of bias, and rated certainty of evidence.

DATA SYNTHESIS

Forty-five trials involving 34 082 participants who received anticoagulation for atrial fibrillation (AF) (11 trials), venous thromboembolism (VTE) (11 trials), thromboprophylaxis (6 trials), prevention of dialysis access thrombosis (8 trials), and cardiovascular disease other than AF (9 trials) were included. All but the 8 trials involving patients with ESKD excluded participants with creatinine clearance less than 20 mL/min or estimated glomerular filtration rate less than 15 mL/min/1.73 m2. In AF, compared with VKAs, NOACs reduced risks for stroke or systemic embolism (risk ratio [RR], 0.79 [95% CI, 0.66 to 0.93]; high-certainty evidence) and hemorrhagic stroke (RR, 0.48 [CI, 0.30 to 0.76]; moderate-certainty evidence). Compared with VKAs, the effects of NOACs on recurrent VTE or VTE-related death were uncertain (RR, 0.72 [CI, 0.44 to 1.17]; low-certainty evidence). In all trials combined, NOACs seemingly reduced major bleeding risk compared with VKAs (RR, 0.75 [CI, 0.56 to 1.01]; low-certainty evidence).

LIMITATION

Scant evidence for advanced CKD or ESKD; data mostly from subgroups of large trials.

CONCLUSION

In early-stage CKD, NOACs had a benefit-risk profile superior to that of VKAs. For advanced CKD or ESKD, there was insufficient evidence to establish benefits or harms of VKAs or NOACs.

PRIMARY FUNDING SOURCE

None. (PROSPERO: CRD42017079709).

Blood Biomarkers of Heart Failure and Hypercoagulation to Identify Atrial Fibrillation-Related Stroke

Background and Purpose- Occult atrial fibrillation (AF) causes a relevant proportion of initially cryptogenic stroke (CS), but prolonged rhythm monitoring is difficult to apply to all such patients. We hypothesized that blood biomarkers indicating heart failure (NT-proBNP [N-terminal pro-brain natriuretic peptide]) and hypercoagulability (D-dimer, AT-III [antithrombin-III]) were associated with AF-related stroke and could serve to predict the likelihood of AF detection in CS patients early on. Methods- Over a 1-year period, we prospectively applied a defined etiologic work-up to all ischemic stroke patients admitted to our stroke unit. If no clear stroke cause was detected (CS), patients underwent extended in-hospital cardiac rhythm monitoring (≥72 hours). Blood to determine biomarker levels was drawn within 24 hours after admission. Results- Of 429 patients, 103 had AF-related stroke. Compared with noncardiac stroke patients (n=171), they had higher NT-proBNP (1867 versus 263 pg/ml) and D-dimer levels (1.1 versus 0.6 µg/ml), and lower AT-III concentration (89% versus 94%). NT-proBNP ≥505 pg/ml distinguished AF-related from noncardiac stroke with a sensitivity of 93% and a specificity of 72%. D-dimer and AT-III cutoffs had lower sensitivities (61% and 53%) and specificities (58% and 69%) for AF-related stroke. Of all initially 143 CS patients, 14 were diagnosed with AF during in-hospital monitoring. The preidentified NT-proBNP cutoff ≥505 pg/ml correctly predicted AF in 12 of them (86%, negative predictive value: 98%), while D-dimer and AT-III cutoffs were noncontributory. Conclusions- This study supports the association of NT-proBNP and to a lesser extent of hypercoagulation markers with AF-related stroke. NT-proBNP seems helpful in selecting CS patients for immediate extended cardiac rhythm monitoring to detect occult AF whereby levels <505 pg/ml seem to have a high-negative predictive value.

Effectiveness and Safety of Contemporary Oral Anticoagulants Among Asians With Nonvalvular Atrial Fibrillation

Background and Purpose- Limited evidence exists on the effectiveness and safety of warfarin and all 4 available non-vitamin K antagonist oral anticoagulants (NOACs) from current clinical practice in the Asian population with nonvalvular atrial fibrillation. We aimed to evaluate the comparative effectiveness and safety of warfarin and 4 NOACs. Methods- We studied a retrospective nonrandomized observational cohort of oral anticoagulant naïve nonvalvular patients with atrial fibrillation treated with warfarin or NOACs (rivaroxaban, dabigatran, apixaban, or edoxaban) from January 2015 to December 2017, based on the Korean Health Insurance Review and Assessment database. For the comparisons, warfarin to 4 NOACs and NOAC to NOAC comparison cohorts were balanced using the inverse probability of treatment weighting. Ischemic stroke, intracranial hemorrhage, gastrointestinal bleeding, major bleeding, and a composite clinical outcome were evaluated. Results- A total of 116 804 patients were included (25 420 with warfarin, 35 965 with rivaroxaban, 17 745 with dabigatran, 22 177 with apixaban, and 15 496 with edoxaban). Compared with warfarin, all NOACs were associated with lower risks of ischemic stroke, intracranial hemorrhage, gastrointestinal bleeding, major bleeding, and composite outcome. Apixaban and edoxaban showed a lower rate of ischemic stroke compared with rivaroxaban and dabigatran. Apixaban, dabigatran, and edoxaban had a lower rate of gastrointestinal bleeding and major bleeding compared with rivaroxaban. The composite clinical outcome was nonsignificantly different for apixaban versus edoxaban. Conclusions- In this large contemporary nonrandomized Asian cohort, all 4 NOACs were associated with lower rates of ischemic stroke and major bleeding compared with warfarin. Differences in clinical outcomes between NOACs may give useful guidance for physicians to choose drugs to fit their particular patient clinical profile.

Reversal agents for direct oral anticoagulants: considerations for hospital physicians and intensivists

Direct oral anticoagulants (DOACs) include dabigatran etexilate, a direct thrombin inhibitor, and specific inhibitors of activated coagulation factor X (FXa; e.g. apixaban, betrixaban, edoxaban, rivaroxaban). DOACs are associated with lower rates of major and fatal bleeding events compared with warfarin. Clinicians may need to achieve rapid reversal of anticoagulation effects of the DOACs in an emergency setting. Idarucizumab and andexanet alfa, which reverse the anticoagulant effects of dabigatran and FXa inhibitors, respectively, are DOAC reversal agents available in the US. Other reversal agents (e.g. ciraparantag for heparins, DOACs) are in development. Alternative nonspecific agents (e.g. fresh frozen plasma, prothrombin complex concentrate) are available. Nonspecific prohemostatic agents can counteract the anticoagulant action of DOACs in emergency situations, when specific reversal agents are unavailable. However, specific reversal agents are efficacious and safe and should be preferred when available. In this review, we discuss practical issues in the initiation of DOAC therapy, situations where reversal may be needed, coagulation assays, reversal agents, and post-reversal complications in the context of published evidence and guidelines.

Intracranial Hemorrhage and Intracranial Hypertension

Central nervous system hemorrhage has multiple pathophysiologic etiologies, including intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH), and traumatic brain injury (TBI). Given the nuances intrinsic to each of these etiologies and pathophysiologic processes, optimal blood pressure varies significantly and depends on type of hemorrhage and individual characteristics. This article reviews the most current evidence regarding blood pressure targets and provides guidance on reversal of anticoagulation for TBI, ICH, and SAH. It also describes the assessment, optimal therapeutic targets, and interventions to treat intracranial hypertension that can result from TBI, ICH, or SAH.

Direct oral anticoagulants in patients with cancer

Purpose

This review summarizes the available evidence concerning direct oral anticoagulant (DOAC) use to treat venous thromboembolism (VTE) in patients with cancer as well as pertinent safety data on the use of DOACs in patients with both cancer and atrial fibrillation.

Summary

The introduction of DOACs into clinical practice changed the way thrombotic complications are managed and prevented in diverse patient populations, including VTE and atrial fibrillation. Low-molecular-weight heparins have been the standard of care for treating VTE in cancer patients due to superiority over vitamin K antagonists in preventing recurrent VTE. Therefore, widespread DOAC use for VTE in patients with active cancer has not been adopted.

Conclusion

Recent randomized clinical trials (SELECT-D, Hokusai VTE Cancer) have provided evidence that DOACs may have a role in treating VTE in cancer patients.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Oral anticoagulant monitoring: Are we on the right track?

Vitamin K antagonists (VKAs) cannot be administered without regular monitoring in order to assure their efficacy and safety. Indeed, if well managed, the VKAs appear to be no less efficacious or safe than the newer direct oral anticoagulants (DOACs). Although it is claimed that no regular monitoring of the DOACs is needed, their levels are increasingly being measured under a variety of circumstances, for example, prior to surgery, in suspected overdose, to confirm effective reversal, in patients with malabsorption and to assess patient compliance. Although no therapeutic range has been identified for the DOACs, it has been demonstrated for dabigatran and edoxaban that their antithrombotic effect increases gradually with increasing concentrations and that the risk of major bleeding also gradually increases. Furthermore, it has been determined that almost all dabigatran-related thrombotic events occur in patients with the lowest quartile concentration of the drug. This suggests that to assure an ideal effect of DOACs in all patients taking them, some form of regular monitoring and dose tailoring should be performed. For the vitamin K antagonists, the best outcome is obtained using formal algorithms and centralized management. Furthermore, data suggest that replacing the standard prothrombin time as a monitoring test may increase the stability of VKA anticoagulation with consequent reduction in thromboembolism without an increase in bleeding. Thus, it is likely that the outcome of all current oral anticoagulants can be improved in the coming years by improving monitoring and tailoring their effect.

Direct-Acting Oral Anticoagulants in Critically Ill Patients

The direct-acting oral anticoagulants (DOACs) have been increasingly used over vitamin K antagonists in recent years because they do not require monitoring and have an immediate anticoagulation effect. In general, DOACs have exhibited a better safety profile and noninferiority for prophylaxis and treatment of venous thromboembolism (VTE) and stroke prevention in patients with atrial fibrillation compared with vitamin K antagonists in the non-ICU population; whether this finding holds true in patients who are critically ill remains unknown. The current review addresses the role of DOACs in special ICU populations, use of these agents for VTE prophylaxis, perioperative management of DOACs, drug monitoring, and potential drug interactions of DOACs in critically ill patients. Adverse events and available reversal agents for DOACs are also discussed.

Feasibility and safety of a 12-week INR follow-up protocol over 2 years in an anticoagulation clinic: a single-arm prospective cohort study

The 2012 American College of Chest Physicians' guidelines recommended a 12-week INR follow-up interval may be appropriate for patients on stable warfarin doses. Limited evidence supports this recommendation. A single-arm, prospective cohort study over 24 months was completed in a Veterans Affairs anticoagulation clinic to determine the long-term feasibility and safety of implementing an extended INR follow-up interval in Veterans on stable doses of warfarin. Participants were required to have a stable warfarin dose for 6 months prior to enrollment. A prespecified protocol was used to titrate, extend, and manage the INR interval up to 12 weeks. Scheduling of extended INR intervals was a primary outcome. Safety outcomes included major and serious bleeding and thromboembolic events. A post-hoc comparison of baseline characteristics between individuals who were scheduled for at least 4 consecutive 12-week INR follow-up intervals and those who were not was completed. Of the 50 participants, 36 (72%) were scheduled for at least one 12-week interval and 15 (30%) were scheduled for 4 consecutive intervals. There were 2 thromboembolic events that occurred in 1 participant. There were 28 major and serious bleeding events in 19 participants; 8 occurred while on the extended INR interval. In the post-hoc analysis, no participants scheduled for 4 consecutive 12-week intervals had heart failure. Based on 2 years of monitoring, a 12-week INR follow-up interval using a detailed protocol with titration of INR interval extension appears feasible for a subset of patients. Patients with heart failure may not be suitable for this intervention.

Antithrombotic Therapy in Patients With Atrial Fibrillation After Percutaneous Coronary Intervention During 2-Year Follow-Up, from a Nationwide Population Study

Patients with atrial fibrillation (AF) who underwent percutaneous coronary intervention (PCI) are recommended to receive oral anticoagulants (OAC) and concomitant antiplatelet agents followed by OAC monotherapy continued beyond a year after PCI. However, long-term prescription patterns of antithrombotic therapy in real-world clinical practice were not fully investigated. From the National Health Insurance Service database of Korea, we obtained records of patients with AF who underwent PCI between 2009 and 2013. Patients without repeated PCI or death within 2 years following the procedure were included. Prescription records of antithrombotic therapy including anticoagulants and antiplatelet agents were reviewed at 3-month intervals after discharge. We investigated 8,891 patients. At discharge, 76.1% of the patients received dual antiplatelet therapy (DAPT) and only 17.1% received OAC. Although the proportion of patients receiving DAPT gradually decreased, >70% of patients received only antiplatelet agents (DAPT or single antiplatelet therapy) a year after PCI. During the 2-year follow-up, the proportion of patients receiving OAC remained <20%, and only 1.5% of the patients received OAC monotherapy a year after PCI. Female gender, previous myocardial infarction, peripheral vascular disease, and prescription of DAPT at discharge were associated with underprescription of OAC a year after PCI. In conclusion, a significant proportion (76%) of patients with AF who underwent PCI were not prescribed OAC at discharge despite the high risk of stroke contrary to the current guidelines. Most patients continued to receive antiplatelet agents without OAC beyond the 1-year time point after PCI.