Antithrombotic Therapy For Stroke Prevention Research Articles

Abstract 10984: Alert-Based Computerized Decision Support for High-Risk Ambulatory Clinic Patients With Atrial Fibrillation Not Prescribed Anticoagulation: A Randomized, Controlled Trial (AF-Alert2)

Introduction: Despite widely available risk stratification tools, safe and effective anticoagulants, and guideline recommendations, antithrombotic therapy for stroke prevention in atrial fibrillation (AF) is under-prescribed in ambulatory clinic patients. Hypothesis: We hypothesized that alert-based computerized decision support (CDS) would increase anticoagulation prescription in ambulatory clinic patients with AF and high-risk for stroke. Methods: We enrolled 798 patients (CHA 2 DS 2- VASc score≥2) with AF who were not prescribed anticoagulant therapy and had an ambulatory clinic visit at Brigham and Women’s Hospital. Patients were randomly allocated, according to Attending Physician of record, to intervention (alert-based CDS) versus control (no notification). The primary efficacy outcome was the frequency of anticoagulant prescription. Results: The CDS tool assigned 395 and 403 patients to the alert and control groups, respectively. Patients in the alert group were more likely to be prescribed anticoagulation within 48 hours of the clinic visit (15.4% vs. 7.7%, p<0.001) and at 90 days (17.2% vs. 9.9%, p<0.01). Direct oral anticoagulants (DOACs) comprised the majority of increased prescriptions of anticoagulation at 48 hours and 90 days. No differences in stroke, TIA, or systemic embolic events (0% vs. 0.8%, p=0.09), symptomatic VTE (0.5% vs. 1%, p=0.43), CV mortality (0.5% vs. 0.7%, p=0.99), or a composite of major adverse cardiovascular events (2.8% vs. 2.5%, p=0.79) were observed at 90 days ( Figure ). Conclusions: An alert-based CDS strategy increased anticoagulation in ambulatory clinic patients with AF and high-risk for stroke who were not receiving anticoagulation at the time of the office visit. ClinicalTrials.gov Identifier: NCT02958943

Effectiveness and Safety of Antithrombotic Medication in Patients With Atrial Fibrillation and Intracranial Hemorrhage: Systematic Review and Meta-Analysis

For patients with atrial fibrillation who survive an intracranial hemorrhage (ICrH), the decision to offer oral anticoagulation (OAC) is challenging and necessitates balancing risk of thromboembolic events with risk of recurrent ICrH. This systematic review assesses the effectiveness and safety of OAC and/or antiplatelets in patients with atrial fibrillation with nontraumatic ICrH. Bibliographic databases CENTRAL, MEDLINE, EMBASE, and CINAHL were searched. Articles on adults with atrial fibrillation with spontaneous ICrH (intracerebral, subdural, and subarachnoid), receiving antithrombotic therapy for stroke prevention were eligible for inclusion. Twenty articles (50 470 participants) included 2 randomized controlled trials (n=304)' 8 observational studies, 8 cohort studies, and 2 studies that meta-analyzed individual-level data from observational studies. OAC therapy was associated with a significant reduction in thromboembolic events (summary relative risk [sRR], 0.51 [95% CI, 0.30-0.86], heterogeneity I2=2%; P=0.39, n=5 studies) and all-cause mortality (sRR, 0.52 [95% CI, 0.38-0.71], heterogeneity I2=0; P=0.44, n=3 studies). OAC therapy was not associated with an increased risk of recurrent ICrH (sRR, 1.44 [95% CI, 0.38-5.46], heterogeneity I2=70%, P=0.02, n=5 studies). Nonvitamin K antagonist OACs were more effective at reducing the risk of thromboembolic events (sRR, 0.65 [95% CI, 0.44-0.97], heterogeneity I2=72%, P=0.03, n=3 studies) and were associated with a lower risk of recurrent ICrH (sRR, 0.52 [95% CI, 0.40-0.67], heterogeneity I2=0%, P=0.43, n=3 studies) than warfarin. In nontraumatic ICrH survivors with atrial fibrillation, OAC therapy is associated with a reduced risk of thromboembolic events and all-cause mortality without significantly increasing risk of recurrent ICrH. This finding is primarily based on observational data, and further larger randomized controlled trials are needed to corroborate or refute these findings.

PO-620-04 INTRA-OPERATIVE FINDINGS WITH MASSIVE DEVICE-RELATED THROMBUS AFTER PERCUTANEOUS LEFT ATRIAL APPENDAGE CLOSURE: MECHANISTIC INSIGHTS

Left atrial appendage closure (LAAC) devices are an alternative to antithrombotic therapy for stroke prevention in high-risk patients with atrial fibrillation who are not candidates for systemic anticoagulation. However, device related thrombus (DRT) has an observed incidence of ∼4% after LAAC. The mechanism of massive thrombus formation remains incompletely understood.

Antithrombotic Therapy for Stroke Prevention in Patients With Ischemic Stroke With Aspirin Treatment Failure.

Many older patients presenting with acute ischemic stroke were already taking aspirin before admission. However, the management strategy for patients with aspirin treatment failure has not been fully established. We used data from the American Heart Association Get With The Guidelines Stroke Registry to describe discharge antithrombotic treatment patterns among Medicare beneficiaries with ischemic stroke who were taking aspirin before their stroke and were discharged alive from 1734 hospitals in the United States between October 2012 and December 2017. Of 261 634 ischemic stroke survivors, 100 016 (38.2%) were taking aspirin monotherapy before stroke. Among them, 44.4% of patients remained on aspirin monotherapy at discharge (20.9% 81 mg, 18.2% 325 mg, 5.3% other or unknown dose). The next most common therapy choice was dual antiplatelet therapy (24.6%), followed by clopidogrel monotherapy (17.8%). The remaining 13.2% of patients were discharged on either aspirin/dipyridamole, warfarin, or nonvitamin K antagonist oral anticoagulants with or without antiplatelet, or no antithrombotic therapy at all. Nearly half of patients with ischemic stroke while on preventive therapy with aspirin are discharged on aspirin monotherapy without changing antithrombotic class, while the other half are discharged on clopidogrel monotherapy, dual antiplatelet therapy, or other less common agents. These findings emphasize the need for future research to identify best management strategies for this very common and complex clinical scenario.

Antithrombotic therapy for stroke prevention in patients with atrial fibrillation who survive an intracerebral haemorrhage: results of an EHRA survey.

The aim of this survey is to provide a snapshot of current practice regarding antithrombotic therapy (ATT) in patients with atrial fibrillation (AF) comorbid with intracerebral haemorrhage (ICH). An online survey was distributed to members of the European Heart Rhythm Association. A total of 163 clinicians responded, mostly cardiologists or electrophysiologists (87.7%), predominantly working in University hospitals (61.3%). Most respondents (47.2%) had seen one to five patients with AF comorbid with ICH in the last 12 months. Among patients sustaining an ICH on oral anticoagulation (OAC), 84.3% respondents would consider some form of ATT post-ICH, with 73.2% preferring to switch from a vitamin-K antagonist (VKA) to a non-VKA oral anticoagulant (NOAC) and 37.2% preferring to switch from one NOAC to another. Most (36.6%) would restart OAC >30 days post-ICH. Among patients considered unable to take OAC, left atrial appendage occlusion procedure was the therapy of choice in 73.3% respondents. When deciding on ATT, respondents considered patient's CHA2DS2-VASc score, ICH type, demographics, risk factors, and patient adherence. The main reason for not restarting or commencing ATT was concern about recurrent ICH (80.8%). National or international clinical guidelines would be advantageous to support decision-making (84.3%). Other helpful resources reported were multidisciplinary team involvement (46.9%) and patient education (82%). In summary, most survey respondents would prescribe OAC therapy for patients with AF who have sustained an ICH on OAC and would restart OAC >30 days post-ICH. The risk of recurrent ICH was the main reason for not prescribing any ATT post-ICH.

Abstract 14763: Patients With a Perceived High-bleeding Risk in a Randomized Controlled Trial of Alert-based Computerized Decision Support for Stroke Prevention in Atrial Fibrillation: An Af-Alert Substudy

Introduction: A perceived increased risk of bleeding is one of the most frequent reasons for failure to prescribe anticoagulation for stroke prevention in atrial fibrillation (AF). We previously conducted a randomized controlled trial of alert-based computerized decision support (CDS) to increase prescription of antithrombotic therapy in 458 high-risk hospitalized patients with AF who were not being anticoagulated. Hypothesis: We hypothesized that patients with a perceived high risk for bleeding would have a similar HAS-BLED score and rate of major and clinically-relevant non-major bleeding. Methods: To determine the clinical characteristics and outcomes of these patients determined to be high-risk for bleeding, we analyzed the 248 patients in the alert group. Results: A perceived high risk of bleeding was the most common reason (77%) for omitting antithrombotic therapy. Median HAS-BLED scores were similar in these patients compared with those who were not deemed to have an increased bleeding risk (3 vs. 3, p=0.44). Despite being categorized as too high-risk for bleeding to receive antithrombotic therapy for stroke prevention at the time of the alert, nearly 12% of these patients were ultimately prescribed anticoagulation over the ensuing 90 days. The frequency of major and clinically-relevant non-major bleeding was similar between the two groups. Conclusions: In conclusion, a perceived high risk of bleeding was the most common reason for failure to prescribe antithrombotic therapy after the CDS alert. History of a prior bleeding event or underlying bleeding disorder was not reflected in a higher HAS-BLED score. Implementation of an alert-based CDS with specific attention to assessment of bleeding risk and mitigation warrants further study to encourage adherence to evidence-based clinical practice guideline recommendations for stroke prevention in AF.

Patients with perceived high-bleeding risk and computerized decision support for stroke prevention in atrial fibrillation: an AF-ALERT substudy : Piazza: outcomes of high-bleeding risk AF patients.

A perceived increased risk of bleeding is one of the most frequent reasons for withholding anticoagulation for stroke prevention in atrial fibrillation (AF). We previously conducted a randomized controlled trial of alert-based computerized decision support to increase prescription of anticoagulation in hospitalized patients with AF. To determine the clinical characteristics and outcomes of those patients whose inpatient health care providers received a computer alert, we analyzed all 248 patients in the alert group. Patients for whom providers elected to omit anticoagulation and provided a rationale of a perceived high risk of bleeding were compared with those who were not designated as high-risk. Perceived high risk of bleeding was the most common reason (77%) for omitting anticoagulation. Median HAS-BLED scores were similar in these patients compared with those who were not deemed to have an increased bleeding risk (3 vs. 3, p = 0.44). Despite being categorized as too high-risk for bleeding to receive antithrombotic therapy at the time of the alert, nearly 12% of these patients were ultimately prescribed anticoagulation by 90days. The frequency of major and clinically-relevant non-major bleeding was similar between the groups. The frequency of death, myocardial infarction, stroke, or systemic embolic event was similar in both groups (10.2% vs. 12.4%, p = 0.59). In conclusion, a perceived high risk of bleeding was the most common reason for omission of anticoagulation in patients with AF after a computerized alert. Perceived high risk of bleeding was not reflected in a higher HAS-BLED score.Clinical trial registration: ClinicalTrials.gov Identifier: NCT02339493 https://clinicaltrials.gov/ct2/show/NCT02339493 In a randomized controlled trial of computerized decision support to increase prescription of antithrombotic therapy in hospitalized patients with atrial fibrillation (AF), a perceived high risk of bleeding was the most common reason (77%) for omitting antithrombotic therapy after an on-screen alert. Median HAS-BLED scores were similar in these patients compared with those who were not deemed to have an increased bleeding risk (3 vs. 3, p = 0.44). Despite being categorized as too high-risk for bleeding to receive antithrombotic therapy for stroke prevention at the time of the alert, nearly 12% of these patients were ultimately prescribed anticoagulation over the ensuing 90days.

Cardiologists' and nephrologists' management of atrial fibrillation in hemodialysis patients .

Antithrombotic therapy for stroke prevention in atrial fibrillation (AF) is considered a standard of care, but for hemodialysis (HD) patients the benefits are unclear, and bleeding risks are high. Our study objective was to compare cardiologists' and nephrologists' stroke prevention practices in different patient risk scenarios. A cross-sectional, online survey was distributed to members of three Canadian physician societies (Nephrology, Cardiovascular, Heart Rhythm), and to cardiologists affiliated with three Canadian Universities. The questionnaire included four AF scenarios in HD patients with varying stroke and bleeding risks. Physicians selected one of six antithrombotic therapy options for each scenario. Cardiologists were 3 times more likely than nephro-logists to choose anticoagulant therapy over both antiplatelet and no drug therapy, regardless of stroke or bleeding risk (p<0.001). Physicians' drug therapy choices in regards to level of stroke and bleeding risk reflected the expected pattern based on current evidence. Cardiologists were more likely to prescribe anticoagulant therapy for AF in the HD population compared to nephrologists, regardless of patient stroke or bleeding risk.

Antithrombotic Therapy for Stroke Prevention.

Antithrombotic Therapy for Stroke Prevention.

Temporal trends of antithrombotic therapy for stroke prevention in Korean patients with non-valvular atrial fibrillation in the era of non-vitamin K antagonist oral anticoagulants: A nationwide population-based study.

BackgroundFollowing their introduction, the non-vitamin K antagonist oral anticoagulants (NOACs) are increasingly prescribed in Asia for stroke prevention in patients with non-valvular atrial fibrillation (AF). Few contemporary data are available on temporal trends in antithrombotic therapy use in Asian countries, in the era of NOACs.Methods and resultsUsing the National Health Insurance Service database of the entire Korean adult AF population, the use of aspirin, vitamin K antagonist, and NOACs between 2008 and 2015 were analyzed (n = 276,246 in 2015). Most of the included cohort had CHA2DS2-VASc score ≥ 2 (78.2% in 2008 and 83.2% in 2015), yet approximately 17% were prescribed no antithrombotic therapy throughout the study period. Aspirin prescription consistently decreased (from 48.2% to 31.5%) over time, while OAC prescription significantly increased from 34.7% to 50.6%. NOAC prescriptions accounted for 50% of total OAC prescription in 2015. Similar trends in antithrombotic therapy were found both in men and in women, but women were more likely to be undertreated with OAC. Female gender, presence of vascular disease and prior intracranial hemorrhage were associated with OAC underuse.ConclusionsBetween 2008 and 2015, a greater proportion of AF patients received OAC treatment with increasing NOAC prescription trends in the recent 3 years. A substantial proportion (approx. 50%) of Korean patients with AF still remain undertreated.

Contemporary utilization of antithrombotic therapy for stroke prevention in patients with atrial fibrillation: an audit in an Australian hospital setting.

To document antithrombotic utilization in patients with nonvalvular atrial fibrillation (NVAF), particularly, recently approved NOACs (nonvitamin K antagonist oral anticoagulants) and warfarin; and identify factors predicting the use of NOACs versus warfarin. A retrospective audit was conducted in an Australian hospital. Data pertaining to inpatients diagnosed with atrial fibrillation (AF) admitted between January and December 2014 were extracted. This included patient demographics, risk factors (stroke, bleeding), social history, medical conditions, medication history, medication safety issues, medication adherence, and antithrombotic prescribed at admission and discharge. Among 199 patients reviewed, 84.0% were discharged on antithrombotics. Anticoagulants (± antiplatelets) were most frequently (52.0%) prescribed (two-thirds were prescribed warfarin, the remainder NOACs), followed by antiplatelets (33.0%). Among 41 patients receiving NOACs, 59.0% were prescribed rivaroxaban, 24.0% dabigatran, and 17.0% apixaban. Among patients aged 75 years and over, antiplatelets were most frequently used (37.0%), followed by warfarin (33.0%), then NOACs (14.0%). Compared with their younger counterparts, patients aged 75 years and over were significantly less likely to receive NOACs (14.0% versus 28.0%, p = 0.01). Among the 'most eligible' patients (Congestive Cardiac Failure, Hypertension (, Age ⩾ 75 years, Age= 65-74 years, Diabetes Mellitus, Stroke/ Transient Ischaemic Attack/ Thromboembolism, Vascular disease, Sex female[CHA2DS2-VASc] score ⩾2 and no bleeding risk factors), 46.0% were not anticoagulated on discharge. Patients with anaemia (68.0% versus 86.0%, p = 0.04) or a history of bleeding (65.0% versus 87.0%, p = 0.01) were less likely to receive antithrombotics compared with those without these risk factors. Warfarin therapy was less frequently prescribed among patients with cognitive impairment compared with patients with no cognitive issues (12.0% versus 23.0%, p = 0.01). Multivariate logistic regression modelling identified that patients with renal impairment were 3.6 times more likely to receive warfarin compared with NOACs (odds ratio = 3.6, 95% confidence interval = 0.08-0.90, p = 0.03, 60.0% correctly predicted; Cox and Snell R2 = 0.51, Nagelkerke R2 = 0.69). Despite the availability of NOACs, warfarin remains a preferred treatment option, particularly among patients with renal impairment. The high proportion of eligible patients still being prescribed antiplatelet therapy or 'no therapy' needs to be addressed.

Regional Differences in Antithrombotic Treatment for Atrial Fibrillation: Insights from the GLORIA-AF Phase II Registry.

Introduction Although guideline-adherent antithrombotic therapy (ATT) for stroke prevention in atrial fibrillation (AF) is associated with lower mortality and thromboembolism, ATT uptake shows geographic variation worldwide. We aimed to assess thromboembolic risk and baseline ATT by geographic region and identify factors associated with prescription of ATT in a large, truly global registry of patients with recently diagnosed AF. Methods and Results Our analysis comprises 15,092 patients newly diagnosed with non-valvular AF at risk for stroke, enrolled in Phase II of Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation (GLORIA-AF). Global oral anticoagulation (OAC) use was 79.9%, being highest in Europe (90.1%), followed by Africa/Middle East (87.4%) and Latin America (85.3%), North America (78.3%) and Asia (55.2%). Among OAC users, vitamin K antagonists (VKAs) have been replaced by non-VKA OACs (NOACs) as the more prevalent OAC option in all regions, with highest use in North America (66.5%) and lowest in Asia (50.2%). In Asia, OAC was 80.4% in community hospitals but only 49.8% in university hospitals and 42.6% in specialist offices, and varied from 21.0% in China to 89.7% in Japan (NOACs at 5.8% in China and 83.3% in Japan). Globally, 76.5% of low-risk patients were prescribed ATT (46.1% OAC), whereas 17.7% high-risk patients were not anticoagulated (Europe 8.8%; North America 18.9%; Asia 42.4%). Conclusion Substantial inter- and intra-regional differences in ATT for stroke prevention in AF are evident in this global registry. While guideline-adherent ATT can be further improved, NOACs are the main contributor to high OAC use worldwide.

Management of blunt cerebrovascular injury (BCVI) in the multisystem injury patient with contraindications to immediate anti-thrombotic therapy

IntroductionPractice management guidelines for screening and treatment of patients with blunt cerebrovascular injury (BCVI) have been associated with a decreased risk of ischemic stroke. Treatment: of patients with BCVI and multisystem injuries that delays immediate antithrombotic therapy remains controversial. The purpose of this study was to determine the timing of BCVI treatment initiation, the incidence of stroke, and bleeding complications as a result of antithrombotic therapy in patients with isolated BCVI in comparison to those with BCVI complicated by multisystem injuries. Materials and methodsThis study was a retrospective review of all adult blunt trauma patients admitted to a level 1 trauma center from 2009 to 2014 with a diagnosis of BCVI. ResultsA total of 28,305 blunt trauma patients were admitted during the study period. Of these, 323 (1.1%) had 481 BCEVIs and were separated into two groups. Isolated BCVI was reported in 111 (34.4%) patients and 212 (65.6%) patients had accompanying multisystem injuries (traumatic brain injury (TBI), solid organ injury, or spinal cord injury) that contraindicated immediate antithrombotic therapy. Treatment: started in patients with isolated BCVI at a median time of 30.3 (15, 52) hours after injury in contrast to 62.4 (38, 97) hours for those with multisystem injuries (p<0.001). The incidence of stroke was identical (9.9%) between groups and no bleeding complications related to antithrombotic therapy were identified. ConclusionThe lack of bleeding complications and equivalent stroke rates between groups suggests that the presence of TBI, solid organ injury, and spinal cord injury are not contraindications to anti-thrombotic therapy for stroke prevention in patients with BCVI.

Prevalence of Atrial Fibrillation and Antithrombotic Therapy in Hemodialysis Patients: Cross-Sectional Results of the Vienna InVestigation of AtriaL Fibrillation and Thromboembolism in Patients on HemoDIalysis (VIVALDI).

BackgroundAtrial fibrillation (AF) adds significant risk of stroke and thromboembolism in patients on hemodialysis (HD). The aim of this study was to investigate the prevalence of AF in a population-based cohort of HD patients and practice patterns of antithrombotic therapy for stroke prevention in AF.MethodsThe Vienna InVestigation of AtriaL fibrillation and thromboembolism in patients on hemodialysis (VIVALDI), an ongoing prospective observational cohort study, investigates the prevalence of AF and the risk of thromboembolic events in HD patients in Vienna, Austria. We analyzed cross-sectional data of 626 patients (63.4% men, median age 66 years, approx. 73% of HD patients in Vienna), who provided informed consent. A structured interview with each patient was performed, recent and archived ECGs were viewed and medical histories were verified with electronic records.ResultsThe overall prevalence of AF was 26.5% (166 patients, 71.1% men, median age 72 years) of which 57.8% had paroxysmal AF, 3.0% persistent AF, 32.5% permanent AF, and 6.6% of patients had newly diagnosed AF. The median CHA2DS2-VASc Score was 4 [25th-75th percentile 3–5]. In multivariable analysis, AF was independently associated with age (odds ratio: 1.05 per year increase, 95% confidence interval: 1.03–1.07), male sex (1.7, 1.1–2.6), history of venous thromboembolism (2.0, 1.1–3.6), congestive heart failure (1.7, 1.1–2.5), history of or active cancer (1.5, 1.0–2.4) and time on HD (1.08 per year on HD, 1.03–1.13). Antithrombotic treatment was applied in 84.4% of AF patients (anticoagulant agents in 29.5%, antiplatelet agents in 33.7%, and both in 21.1%). In AF patients, vitamin-K-antagonists were used more often than low-molecular-weight heparins (30.1% and 19.9%).ConclusionsThe prevalence of AF is high amongst HD patients and is associated with age, sex, and distinct comorbidities. Practice patterns of antithrombotic treatment indicate a lack of consensus for stroke prevention in HD patients with AF.

Selecting antithrombotic therapy for stroke prevention in atrial fibrillation: Health professionals' feedback on a decision support tool.

A Computerised Antithrombotic Risk Assessment Tool was developed for assisting the selection of antithrombotic therapy based on the risk versus benefit assessment. In view of the recent availability of the novel oral anticoagulants, this tool has been updated to CARATV2.0. To explore health professionals' perspectives on the tool, semi-structured interviews were conducted in seven pharmacists, seven specialists, six general practitioners and six nurses, who were involved in management of antithrombotic therapy for atrial fibrillation. Three overarching themes emerged: (1) CARATV2.0 provides comprehensive structured assessment of patients and could assist with the prescription and review of antithrombotic therapy, (2) subjective issues such as health professionals' and patients' preferences for a particular antithrombotic therapy may affect the usefulness of CARATV2.0 and (3) CARATV2.0 requires integration into existing systems and processes. The majority of health professionals surveyed would like to use CARATV2.0 in practice, believing it would improve antithrombotic use and might reduce stroke incidence.

Utilization of antithrombotic therapy for stroke prevention in atrial fibrillation: a cross-sectional baseline analysis in general practice

Antithrombotics for stroke prevention in atrial fibrillation (AF) are reportedly underutilised. Since the burden of care lies within general practice, attention must be paid to identifying and addressing practice gaps in this setting. The objective of this study was to determine the contemporary utilisation of antithrombotic therapy for stroke prevention in AF within Australian general practice (GP). Data pertaining to AF patients' (aged ≥65years) were collected from GP surgeries in New South Wales, Australia, using purpose-designed data collection forms; extracted data comprised patients' medical histories, current pharmacotherapy, and relevant characteristics. Data pertaining to 393 patients (mean age 78·0±7·0years) were reviewed. Overall, most (98·5%) patients received antithrombotic therapy. Among the 387 patients using antithrombotics, most (94·1%) received mono-therapy. "Warfarin±antiplatelet" was most frequently used (81·7%); 77·5% used "warfarin" as a monotherapy, followed by "dabigatran±clopidogrel" (11·6%), "aspirin" (5·9%) and "clopidogrel" alone (0·8%). High stroke risk and low bleeding risk were associated with increased use of "warfarin±antiplatelet" therapy. Older patients (≥80years) were more likely to receive 'nil therapy' (P=0·04), and less likely to receive dual and triple antithrombotic therapy. We found an encouraging improvement compared to previous studies in the utilisation of antithrombotic therapy for stroke prevention in AF within general practice. Warfarin is now utilised as the mainstay therapy, followed by aspirin, although the novel oral anticoagulants are entering the spectrum of therapies used. Consideration needs to be given to the potential impact of the newer agents and their scope of use.

Decision-making around antithrombotics for stroke prevention in atrial fibrillation: the health professionals' views.

Background For stroke prevention in patients with atrial fibrillation (AF), the decision-making around antithrombotic therapy has been complicated by older age, multiple comorbidities, polypharmacy and the different pharmacological properties of warfarin and the nonvitamin K antagonist oral anticoagulants (NOACs). The complexity of decision-making has been associated with a reluctance by health professionals to use antithrombotic therapy, leading to poor clinical outcomes. In order to improve stroke prevention in patients with AF, the contemporary perspectives of health professionals on the decision-making around antithrombotic therapy needs exploration. Objective To elicit emerging themes describing health professionals' perspectives on the decision-making around antithrombotic therapy for stroke prevention in patients with AF. Setting Sydney metropolitan area of New South Wales, Australia. Method A qualitative study based on face-to-face interviews was conducted from August to October 2014. Seven pharmacists, seven specialists, six general practitioners and six nurses practising in the Sydney metropolitan area and managing antithrombotic therapy for AF were interviewed until theme saturation was achieved in each subgroup. Interview transcripts were analysed using manual inductive coding. Main outcome measure Emerging themes describing health professionals' perspectives on the decision-making around antithrombotic therapy for stroke prevention in patients with AF. Results Three overarching themes emerged. (1) Comprehensive assessment is necessary for decision-making but is not always implemented. Health professionals mostly focused on stroke risk assessment, not on the bleeding risk and medication safety issues. (2) Health professionals from different disciplines have different preferences for antithrombotic therapies. Although the majority of health professionals considered warfarin as the first-line therapy, NOACs were preferred by neurologists and haematologists. (3) Health professionals focused on different aspects of the decision making process: GPs and specialists were concerned about the appropriate prescription of antithrombotics, while pharmacists and nurses focused on daily medication management by patients. Conclusion The decision-making process appears to be partially preference based rather than systematic, and health professionals from various disciplines focus on different parts of the decision-making process.

Choice of antithrombotic therapy in patients with Non Valvular Atrial Fibrillation in real life

Non-valvular atrial fibrillation (NVAF) is the most common cardiac arrhythmia and it is associated with a 5-fold increase in risk of ischemic stroke. Although clinical guidelines recommend antithrombotic therapy for stroke prevention in patients at moderate or high risk for stroke, little is known on the extent to which the increase of the risks influence the choice of the therapy. The aim of the study was to assess the level of adherence to the guidelines for the prevention of thromboembolic risk in patients with NVAF. A population-based cohort study was conducted using administrative data from a local health authority in the Campania Region (~1,000,000 inhabitants). NVAF was defined as one or more claims for atrial fibrillation between July, 2013 and June, 2014 where none of the claims were associated with cardioversion or cardiac ablation during the identification period and there was no evidence of valve-related diagnoses or procedures. The cohort was classified according to the first drug dispensing during 6 months from the discharge date for atrial fibrillation. Patients were categorized in low ischemic stroke risk (LR, score = 0), moderate-risk (MR, score = 1), high-risk (HR, score≥2) according to the CHA2DS2-VASc score. Multivariable logistic regression was used to evaluate the associations between ischemic stroke risk with the choice of non-vitamin K antagonist oral anticoagulants (NOACs) versus vitamin K antagonists (VKAs) therapy. A total of 1963 patients were identified: 4.9% LR, 7.6% MR and 87.5% HR patients. Overall, 36.4% of patients were not treated (LR: 56.7%, MR: 55.0%, HR: 33.7%patients). The Vitamin K antagonists were prescribed to 17% of the patients (LR: 10.3%, MR: 12,1%, HR: 17,8%), NOAC to 12,7% (LR: 10,3%, MR: 8,1%, HR: 13,2%), low-dose aspirin to 17.5% (LR: 13,4%, MR: 15,4%, HR: 17,9%), other antiplatelet to 12,3% (LR: 7,2%, MR: 6,0%, HR: 13,2%). The ischemic stroke was not significantly associated with the choice of anticoagulant drug. High proportion of NVAF patients with CHA2DS2-VASc score of 2 or greater not received oral anticoagulant as recommended. In contrast with recent guidelines, aspirin was commonly prescribed even in HR patients. The stroke risk stratification did not influence the choice of anticoagulant drug.

Safe use of antithrombotics for stroke prevention in atrial fibrillation: consideration of risk assessment tools to support decision-making.

Clinical guidelines advocate stroke prevention therapy in atrial fibrillation (AF) patients, specifically anticoagulation. However, the decision to initiate treatment is based on the risk (bleeding) versus benefit (prevention of stroke) of therapy, which is often difficult to assess. This review identifies available risk assessment tools to facilitate the safe and optimal use of antithrombotic therapy for stroke prevention in AF. Using key databases and online clinical resources to search the literature (1992-2012), 19 tools have been identified and published to date: 11 addressing stroke risk, 7 addressing bleeding risk and 1 integrating both risk assessments. The stroke risk assessment tools (e.g. CHADS2, CHA2DS2-VASc) share common risk factors: age, hypertension, previous cerebrovascular attack. The bleeding risk assessment tools (e.g. HEMORR2HAGES, HAS-BLED) share common risk factors: age, previous bleeding, renal and liver impairment. In terms of their development, six of the stroke risk assessment tools have been derived from clinical studies, whilst five are based on refinement of existing tools or expert consensus. Many have been evaluated by prospective application to data from real patient cohorts. Bleeding risk assessment tools have been derived from trials, or generated from patient data and then validated via further studies. One identified tool (i.e. Computerised Antithrombotic Risk Assessment Tool [CARAT]) integrates both stroke and bleeding, and specifically considers other key factors in decision-making regarding antithrombotic therapy, particularly those increasing the risk of medication misadventure with treatment (e.g. function, drug interactions, medication adherence). This highlights that whilst separate tools are available to assess stroke and bleeding risk, they do not estimate the relative risk versus benefit of treatment in an individual patient nor consider key medication safety aspects. More effort is needed to synthesize these separate risk assessments and integrate key medication safety issues, particularly since the introduction of new anticoagulants into practice.

Regional differences in use of antithrombotic therapy for stroke prevention in atrial fibrillation and associated outcomes: European and Asian insights

Purpose: Few data are available on clinical outcomes in patients with atrial fibrillation (AF) in the Asian region compared with those in Europe. Methods: The population comprised consecutively recruited patients with newly diagnosed (≤6 weeks) non-valvular AF and one or more investigator-defined stroke risk factor(s). The effect of region (Asia vs Europe) on clinical outcomes at 1 year was investigated using a Cox proportional hazards model, adjusting for components of the CHA2DS2VASc risk scheme. Results: Of the 10,614 GARFIELD patients, 2589 were enrolled in Asia (mean age±SD 66±12 years; 38% women) and 6580 in Europe (mean age 72±11 years; 45% women). Mean risk scores were lower in the Asian population: CHADS2 1.6±1.1 vs 2.0±1.2; CHA2DS2VASc 2.7±1.6 vs 3.4±1.6; HAS-BLED 1.2±0.9 vs 1.3±0.9; all p<0.001. Overall use of VKAs initiated at diagnosis of AF was higher in Europe (65% vs 38% in Asia) and antiplatelet use lower (20% vs 37%); 20% of Asian patients received no antithrombotic treatment vs 12% of those in Europe (p<0.001 for overall treatment). VKA use was lower in Asia than in Europe irrespective of risk level (CHA2DS2-VASc <2: 35% vs 58%, respectively, p<0.001; score ≥2: 42% vs 67%, p<0.001). Despite lower overall use of VKAs in Asia, stroke/systemic embolism rates were similar; risk of major bleeding was lower (Table). View this table: Adjusted HRs for events at 1 year Conclusion: These multinational observational data from the GARFIELD Registry suggest that a more risk-based approach to VKA treatment at diagnosis may be applied in Asia versus Europe, resulting in a lower rate of bleeding and equivalent rate of stroke/systemic embolism.