Non-vitamin K-dependent oral anticoagulants have a positive impact on ischaemic stroke severity in patients with atrial fibrillation

Contemporary outcomes of acute ischemic stroke in atrial fibrillation patients on anticoagulation

BACKGROUND

Long-term anticoagulation (AC) therapy reduces the risk of stroke in patients with Atrial Fibrillation (AF). However, data on the impact of AC on in-hospital stroke outcomes is lacking.

METHODS

The National Inpatient Sample was used to identify adult inpatients with AF and a primary diagnosis of ischemic stroke between 2016 and 2020. Data was stratified between AC users and nonusers. A multivariate regression model was used to describe the in-hospital outcomes, adjusting for significant comorbidities.

RESULTS

A total of 655,540 hospitalizations with AF and a primary hospitalization diagnosis of ischemic stroke were included, of which 194,560 (29.7 %) were on long-term AC. Patients on AC tended to be younger (mean age, 77 vs. 78), had a higher average CHA2DS2VASc score (4.48 vs. 4.20), higher rates of hypertension (91 % vs. 88 %), hyperlipidemia (64 % vs. 59 %), and heart failure (34 % vs. 30 %) compared to patients not on long-term AC. Use of AC was associated with decreased in-hospital mortality (aOR [95 % CI]: 0.62 [0.60-0.63]), decreased stroke severity (mean NIHSS, 8 vs. 10), decreased use of tPA (aOR 0.42 [0.41-0.43]), mechanical thrombectomy (aOR 0.85 [0.83-0.87]), intracranial hemorrhage (aOR 0.69 [0.67-0.70]), gastrointestinal bleeding (aOR 0.74 [0.70-0.77]), and discharge to skilled nursing facilities (aOR 0.90 [0.89-0.91]), compared to patients not on AC (P<0.001 for all comparisons).

CONCLUSION

Among patients with AF admitted for acute ischemic stroke, AC use prior to stroke was associated with decreased in-hospital mortality, decreased stroke severity, decreased discharge to SNF, and fewer stroke-related and bleeding complications.

Acute Ischaemic Stroke in Patients Treated with Direct Oral Anticoagulants: Potential Causes, Clinical Characteristics, and Short-Term Outcomes

Introduction

Direct oral anticoagulants (DOAC) are the first-line treatment for primary and secondary acute ischaemic stroke (AIS) prevention in patients with nonvalvular atrial fibrillation (NVAF), but a significant percentage of patients develop AIS despite being treated with DOAC. As the number of DOAC-treated patients is growing, so is the number of patients with AIS on DOAC. The aim of the study was to assess the incidence of AIS with prestroke DOAC treatment among patients hospitalised in the University Hospital in Kraków, to analyse the clinical characteristics of AIS occurring in patients on DOAC, and to identify potential causes of treatment ineffectiveness in this group.

Materials and Methods

In the study, we included all patients hospitalised in the Department of Neurology of the University Hospital in Kraków within one year (July 2022 to June 2023) with the diagnosis of AIS. The group was divided into two subgroups of patients with and without prestroke DOAC treatment. Based on medical files, we retrospectively analysed the profile of cardiovascular risk factors, stroke severity (assessed with National Institutes of Health Stroke Scale, NIHSS), use of causative stroke treatment and short-term outcomes (defined as NIHSS score, modified Rankin scale (mRS) score at discharge, in-hospital mortality, and secondary intracerebral haemorrhage among patients treated with mechanical thrombectomy, MT). Within the DOAC-treated subgroup, we looked for potential causes of AIS occurring despite DOAC treatment (valvular AF, poor adherence to treatment, underdosing, other prothrombotic conditions, aetiology of stroke other than thromboembolic, and drug-drug interactions).

Results

In the study, we included 768 AIS patients. 109 (14.2%) had a history of prestroke DOAC treatment. A potential cause of DOAC treatment failure was identified in the majority of them (n = 63, 57.8%). Patients with prestroke DOAC treatment had worse functional condition before stroke and higher stroke severity on admission but similar short-term outcomes and similar short-term effects of treatment with MT. DOAC (+) and DOAC (-) patients had different profiles of cardiovascular risk factors and different factors associated with short-term outcome. Conclusions and Clinical Implications. A potential cause of AIS occurring in DOAC-treated patients can be identified in most cases and in many of them prevented.

Severity of Ischemic Stroke After Left Atrial Appendage Closure vs Nonwarfarin Oral Anticoagulants

BACKGROUND

Strokes after left atrial appendage closure (LAAC) prophylaxis are generally less severe than those after warfarin prophylaxis-thought to be secondary to more hemorrhagic strokes with warfarin. Hemorrhagic strokes are similarly infrequent with direct oral anticoagulant (DOAC) prophylaxis, so the primary subtype after either LAAC or DOAC prophylaxis is ischemic stroke (IS).

OBJECTIVES

The purpose of this study was to compare the severity of IS using the modified Rankin Scale in atrial fibrillation patients receiving prophylaxis with DOACs vs LAAC.

METHODS

A retrospective analysis was performed of consecutive patients undergoing LAAC at 8 centers who developed an IS (ISLAAC) compared with contemporaneous consecutive patients who developed IS during treatment with DOACs (ISDOAC). The primary outcome was disabling/fatal stroke (modified Rankin Scale 3-5) at discharge and 3 months later.

RESULTS

Compared with ISDOAC patients (n = 322), ISLAAC patients (n = 125) were older (age 77.2 ± 13.4 years vs 73.1 ± 11.9 years; P = 0.002), with higher HAS-BLED scores (3.0 vs 2.0; P = 0.004) and more frequent prior bleeding events (54.4% vs 23.6%; P < 0.001), but similar CHA2DS2-VASc scores (5.0 vs 5.0; P = 0.28). Strokes were less frequently disabling/fatal with ISLAAC than ISDOAC at both hospital discharge (38.3% vs 70.3%; P < 0.001) and 3 months later (33.3% vs 56.2%; P < 0.001). Differences in stroke severity persisted after propensity score matching. By multivariate regression analysis, ISLAAC was independently associated with fewer disabling/fatal strokes at discharge (OR: 0.22; 95% CI: 0.13-0.39; P < 0.001) and 3 months (OR: 0.25; 95% CI: 0.12-0.50; P < 0.001), and fewer deaths at 3 months (OR: 0.28; 95% CI: 0.12-0.64; P < 0.001).

CONCLUSIONS

Ischemic strokes in patients with atrial fibrillation are less often disabling or fatal with LAAC than DOAC prophylaxis.

Should atrial fibrillation be considered a vascular disease? The need for a comprehensive vascular approach

INTRODUCTION

Atrial fibrillation (AF) cannot be considered an isolated disease. Patients with AF should be managed using a comprehensive approach that is not limited to stroke prevention.

AREAS COVERED

In this manuscript, the potential role of AF as a vascular disease that is managed as part of a holistic approach was reviewed.

EXPERT OPINION

The residual risk of stroke in patients with AF reaches 1-2% annually, despite appropriate anticoagulation therapy. Additionally, patients with AF may develop cognitive impairment through stroke-independent pathways. Furthermore, patients with AF may have a higher risk of developing atherosclerotic vascular disease in various vascular beds and chronic kidney disease; conversely, patients with atherosclerotic disease may have an increased risk of developing AF. AF should be considered a truly systemic vascular disease, since it brings together several hemodynamic and systemic changes, including inflammation, oxidative stress, activation of the renin-angiotensin-aldosterone and sympathetic systems, as well as a prothrombotic state and endothelial dysfunction. In this regard, patients with AF should be treated based on a holistic approach that is not limited to oral anticoagulation but includes complete vascular protection.

Global Coagulation Testing in Acute Care Medicine: Back to Bedside?

OBJECTIVES

 Detailed and decisive information about the patients' coagulation status is important in various emergency situations. Conventional global coagulation testing strategies are often used to provide a quick overview, but several limitations particularly in the trauma setting are well described. With the introduction of direct oral anticoagulations (DOACs), a milestone for several disease entities resulting in overall improved outcomes could be reached, but at the same time providing new diagnostic challenges for the emergency situation.

DESIGN

 As an alternative to conventional coagulation tests, there is increasing clinical and scientific interest in the use of early whole blood strategies to provide goal-directed coagulation therapies (GDCT) and hemostatic control in critically ill patients. Viscoelastic hemostatic assays (VHAs) were therefore introduced to several clinical applications and may provide as a bedside point-of-care method for faster information on the underlying hemostatic deficiency.

CONCLUSION

 The use of VHA-based algorithms to guide hemostatic control in emergency situations now found its way to several international guidelines for patients at risk of bleeding. With this qualitative review, we would like to focus on VHA-based GDCT and review the current evidence for its use, advantages, and challenges in the two different clinical scenarios of trauma and intracerebral bleeding/stroke management.

Stroke Prevention in Atrial Fibrillation: A Scientific Statement of JACC: Asia (Part 1)

Atrial fibrillation is the most common sustained cardiac arrhythmia and is associated with substantial increases in the risk of stroke and systemic thromboembolism. With the successful introduction of the first non-vitamin K antagonist direct oral anticoagulant (NOAC) in 2009, the role of vitamin K antagonists has been replaced in most clinical settings except in a few conditions when NOACs are contraindicated. Data for the use of NOACs in different clinical scenarios have been accumulating in the recent decade, and a more sophisticated strategy for atrial fibrillation patients is now warranted. JACC: Asia recently appointed a working group to summarize the most updated information regarding stroke prevention in AF. This statement aimed to provide possible treatment option in daily practice. Local availability, cost, and patient comorbidities should also be considered. Final decisions may still need to be individualized and based on clinicians' discretion. This is the part 1 of the whole statement.

Admission Severity of Atrial-Fibrillation-Related Acute Ischemic Stroke in Patients under Anticoagulation Treatment: A Systematic Review and Meta-Analysis

Background: In non-valvular-associated atrial fibrillation (AF), direct oral anticoagulants (DOAC) are as effective as vitamin K antagonists (VKA) for the prevention of acute ischemic stroke (AIS). DOAC are associated with decreased risk and severity of intracranial hemorrhage. It is unknown if different pre-admission anticoagulants impact the prognosis of AF related AIS (AF-AIS). We sought to analyze the literature to assess the association between pre-admission anticoagulation (VKA or DOAC) and admission severity of AF-AIS. Methods: A Systematic literature search (PubMed and ScienceDirect) between January 2011 to April 2021 was undertaken to identify studies describing the outcome of AF-AIS. Results: A total of 128 articles were identified. Of 9493 patients, 1767 were on DOAC, 919 were on therapeutical VKA, 792 were on non-therapeutical VKA and 6015 were not anticoagulated. In comparison to patients without anticoagulation, patients with therapeutical VKA and under DOAC presented with less severe stroke (MD −1.69; 95% CI [−2.71, −0.66], p = 0.001 and MD −2.96; 95% Cl [−3.75, −2.18], p < 0.00001, respectively). Patients with non-therapeutical VKA presented with more severe stroke (MD 1.28; 95% Cl [0.45, 2.12], p = 0.003). Conclusions: In AF-AIS, patients under therapeutical VKA or DOAC have reduced stroke severity on admission in comparison to patients without any anticoagulation, with higher magnitude of protection for DOAC.

Acute care and secondary prevention of stroke with newly detected versus known atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) in stroke patients can be classified as either "known AF (KAF)", which was confirmed before stroke-onset, or "AF detected after stroke (AFDAS)", which was diagnosed after stroke-onset. While KAF is considered primarily cardiogenic, AFDAS includes patients with stroke-triggered neurogenic arrhythmias. This study aimed to investigate the clinical course of stroke, functional outcome and the value of oral anticoagulation for secondary prevention according to AF subtype.

METHODS

Acute ischemic stroke patients were consecutively enrolled, AF was classified as AFDAS or KAF. Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS) and the three-month functional outcome was measured on the modified Rankin scale. Inverse probability weighting was applied to adjust baseline confounders in patients with AFDAS and KAF. Multivariate logistic regression models were calculated to investigate the value of oral anticoagulation for secondary prevention.

RESULTS

822 stroke patients with AF were included, 234 patients (28.5%) had AFDAS. AFDAS patients had lower prevalence of coronary artery disease, heart failure, and sustained AF, but higher rates of large-vessel occlusion compared to KAF patients. NIHSS-scores were lower in patients on pre-stroke anticoagulation. Oral anticoagulation for secondary prevention was associated with a favorable three-month functional outcome (odds ratio 7.60, 95% confidence interval 3.42-16.88) independently from AF subtype. The rate of stroke recurrence did not differ significantly.

CONCLUSIONS

Clinical characteristics suggest that AFDAS might comprise a distinct pathophysiologic and clinical entity among stroke patients with AF. The benefit of anticoagulation for secondary prevention was not affected by AF subtype.

Association Between Inappropriately Dosed Anticoagulation Therapy With Stroke Severity and Outcomes in Patients With Atrial Fibrillation

Background

Oral anticoagulation (OAC) is effective for stroke prevention in patients with atrial fibrillation. However, some patients experience stroke despite OAC therapy, and knowledge about the impact of prior treatment quality is lacking.

Methods and Results

Patients with atrial fibrillation on OAC therapy who had a first‐time ischemic stroke were identified in the Danish Stroke Registry (2005–2018). Patients treated with vitamin K antagonist (VKA) therapy were compared according to the international normalized ratio just before stroke (international normalized ratio <2 [subtherapeutic], international normalized ratio 2–3 [therapeutic], international normalized ratio >3 [supratherapeutic]), and patients on underdosed, appropriately dosed, and overdosed direct OAC (DOAC) therapy were compared. Stroke severity was determined using the Scandinavia Stroke Scale (0–58 points), and the risk of very severe stroke (0–14 points) was analyzed by multivariable logistic regression. One‐year mortality was determined using multivariable Cox regression. A total of 2319 patients with atrial fibrillation and stroke were included; 1196 were taking a VKA (subtherapeutic [46%], therapeutic [43%], supratherapeutic [11%]), and 1123 were taking DOAC (underdosed [23%], appropriately dosed [60%], and overdosed [17%]). Subtherapeutic and supratherapeutic VKA therapy (compared with therapeutic) and underdosed DOAC therapy (compared with appropriate and underdosed DOAC) patients were older, more often women, and more comorbid. Subtherapeutic VKA therapy was associated with very severe stroke (odds ratio [OR], 2.06 [95% CI, 1.28–3.31]), whereas supratherapeutic VKA therapy was not (OR, 1.24 [95% CI, 0.60–2.57]) compared with therapeutic VKA therapy. Patients on subtherapeutic and supratherapeutic VKA therapy had a higher 1‐year mortality (hazard ratio [HR], 1.66 [95% CI, 1.29–2.13]); HR, 1.55 [95% CI, 1.08–2.22], respectively) than those on therapeutic VKA therapy. Treatment with underdosed or overdosed DOAC therapy was not associated with very severe stroke (OR, 1.27 [95% CI, 0.76–2.15]; OR, 0.73 [95% CI, 0.37–1.43], respectively) and was not associated with 1‐year mortality (HR, 1.09 [95% CI, 0.83–1.44]; HR, 0.82 [95% CI, 0.57–1.18], respectively) than appropriate DOAC.

Conclusions

Half of the patients with atrial fibrillation with stroke were on inappropriate OAC therapy. Subtherapeutic VKA was associated with worse stroke severity and higher mortality rate than therapeutic VKA therapy. Neither underdosed nor overdosed DOAC was associated with worse outcomes in adjusted models compared with appropriately dosed DOAC. This study supports DOAC as a first‐line therapy over VKA.

Off-label-dosing of non-vitamin K-dependent oral antagonists in AF patients before and after stroke: results of the prospective multicenter Berlin Atrial Fibrillation Registry

AIMS

We aimed to analyze prevalence and predictors of NOAC off-label under-dosing in AF patients before and after the index stroke.

METHODS

The post hoc analysis included 1080 patients of the investigator-initiated, multicenter prospective Berlin Atrial Fibrillation Registry, designed to analyze medical stroke prevention in AF patients after acute ischemic stroke.

RESULTS

At stroke onset, an off-label daily dose was prescribed in 61 (25.5%) of 239 NOAC patients with known AF and CHA₂DS₂-VASc score ≥ 1, of which 52 (21.8%) patients were under-dosed. Under-dosing was associated with age ≥ 80 years in patients on rivaroxaban [OR 2.90, 95% CI 1.05-7.9, P = 0.04; n = 29] or apixaban [OR 3.24, 95% CI 1.04-10.1, P = 0.04; n = 22]. At hospital discharge after the index stroke, NOAC off-label dose on admission was continued in 30 (49.2%) of 61 patients. Overall, 79 (13.7%) of 708 patients prescribed a NOAC at hospital discharge received an off-label dose, of whom 75 (10.6%) patients were under-dosed. Rivaroxaban under-dosing at discharge was associated with age ≥ 80 years [OR 3.49, 95% CI 1.24-9.84, P = 0.02; n = 19]; apixaban under-dosing with body weight ≤ 60 kg [OR 0.06, 95% CI 0.01-0.47, P < 0.01; n = 56], CHA₂DS₂-VASc score [OR per point 1.47, 95% CI 1.08-2.00, P = 0.01], and HAS-BLED score [OR per point 1.91, 95% CI 1.28-2.84, P < 0.01].

CONCLUSION

At stroke onset, off-label dosing was present in one out of four, and under-dosing in one out of five NOAC patients. Under-dosing of rivaroxaban or apixaban was related to old age. In-hospital treatment after stroke reduced off-label NOAC dosing, but one out of ten NOAC patients was under-dosed at discharge.

CLINICAL TRIAL REGISTRATION

NCT02306824.

Oral anticoagulation in patients with atrial fibrillation and acute ischaemic stroke: design and baseline data of the prospective multicentre Berlin Atrial Fibrillation Registry

AIMS

The Berlin Atrial Fibrillation Registry was designed to analyse oral anticoagulation (OAC) prescription in patients with atrial fibrillation (AF) and acute ischaemic stroke.

METHODS AND RESULTS

This investigator-initiated prospective multicentre registry enrolled patients at all 16 stroke units located in Berlin, Germany. The ongoing telephone follow-up is conducted centrally and will cover 5 years per patient. Within 2014 and 2016, 1080 patients gave written informed consent and 1048 patients were available for analysis. Median age was 77 years [interquartile range (IQR) 72-83], 503 (48%) patients were female, and 254 (24%) had a transient ischaemic attack (TIA). Overall, 470 (62%) out of 757 patients with known AF and a (pre-stroke) CHA2DS2-VASc ≥ 1 were anticoagulated at the time of stroke. At hospital discharge, 847 (81.3%) of 1042 patients were anticoagulated. Thereof 710 (68.1%) received a non-vitamin K-dependent oral anticoagulant (NOAC) and 137 (13.1%) a vitamin K antagonist (VKA). Pre-stroke intake of a NOAC [odds ratio (OR) 15.6 (95% confidence interval, 95% CI 1.97-122)] or VKA [OR 0.04 (95% CI 0.02-0.09)], an index TIA [OR 0.56 (95% CI 0.34-0.94)] rather than stroke, heart failure [OR 0.49 (95% CI 0.26-0.93)], and endovascular thrombectomy at hospital admission [OR 12.9 (95% CI 1.59-104)] were associated with NOAC prescription at discharge. Patients' age or AF type had no impact on OAC or NOAC use, respectively.

CONCLUSION

About 60% of all registry patients with known AF received OAC at the time of stroke or TIA. At hospital discharge, more than 80% of AF patients were anticoagulated and about 80% of those were prescribed a NOAC.

Effects of dabigatran and rivaroxaban on stroke severity according to the results of routine coagulation tests

Introduction

Prior use of direct oral anticoagulants has been associated with reduced stroke severity in patients with non-valvular atrial fibrillation (NVAF). The aim of this study was to investigate the impact of prothrombin time (PT) and activated partial thromboplastin time (aPTT) on stroke severity in patients who were receiving dabigatran or rivaroxaban at the time of stroke onset.

Materials and methods

We enrolled 107 patients with NVAF who developed acute ischemic stroke while on dabigatran or rivaroxaban and presented within 24 hours to nine hospitals between January 2014 and December 2018. The results of PT and aPTT assays were obtained within 24 hours of stroke onset in all patients. We analyzed PT and aPTT in relation to stroke severity and ischemic lesion volume using correlation and multivariable regression analyses.

Results

Of the 107 patients included, 46 (43.0%) were on dabigatran and 61 (57.0%) were on rivaroxaban. In patients with prior dabigatran use, while aPTT was inversely correlated with admission National Institutes of Health Stroke Scale (NIHSS) score (r = -0.369, p = 0.012) and ischemic lesion volume (r = -0.480, p = 0.005), there was no correlation between PT and either of these variables. Multivariable analysis confirmed the existence of a significant independent inverse relationship between aPTT and NIHSS score at admission (B, -0.201; 95% confidence interval [CI], -0.370 to -0.032; p = 0.005) and between aPTT and ischemic lesion volume (B, -0.076; 95% CI, -0.130 to -0.023; p = 0.007). In patients with prior rivaroxaban use, neither PT nor aPTT was associated with admission NIHSS score or ischemic lesion volume in the correlation and multivariable analyses.

Conclusions

In patients with NVAF who were receiving dabigatran, prolonged aPTT was associated with reduced stroke severity.

Temporal Trends in Pharmacological Stroke Prevention in Patients with Acute Ischemic Stroke and Known Atrial Fibrillation

INTRODUCTION

Oral anticoagulation (OAC) substantially reduces stroke risk in patients with atrial fibrillation (AF) at risk for stroke. Whether non-vitamin K-dependent oral anticoagulants (NOACs) improve OAC use in stroke prevention requires investigation.

METHODS

To investigate temporal trends of OAC use in patients with known AF pre-stroke, we retrospectively analyzed records of 6,803 stroke patients admitted in 2003-2004 (n=1,496), 2008-2010 (n=1,638) or 2013-2015 (n=3,669) to the Charité-Universitätsmedizin Berlin, Germany. Adjusted regression models were used to identify factors associated with OAC use.

RESULTS

Of 1,209 AF patients (mean age 79 years, 55.9% female) with given indication for OAC according to the CHADS₂/CHA₂DS₂-VASc score, 484 (40.0%) were anticoagulated prior to the index stroke, 458 (37.9%) received antiplatelets and 236 (19.5%) had no antithrombotic medication. Compared to 2003-2004 and 2008-2010, there was a higher rate of pre-admission OAC in 2013-2015 (28.2% vs. 49.6%, p<0.001). After adjustment for possible confounders, factors associated with OAC pre-admission were young age (OR 0.74 per decade [95%CI 0.64-0.85]), previous stroke/TIA (OR 1.29 [95%CI 1.00-1.67]), absence of heart failure (OR 0.63 [95%CI 0.47-0.85]) and admission in 2013-2015 (OR 2.45 [95%CI 1.91-3.15]). Prescription of OAC at hospital discharge increased from 2003-2010 compared to 2013-2015 (45.2% vs. 69.5%, p < 0.001).

CONCLUSIONS

Irrespective of temporal trends and despite given indication, more than half of all patients with known AF were not anticoagulated prior to the index stroke. In the NOAC era, there was an increase in OAC intake pre-stroke and a higher rate of OAC prescription at hospital discharge in stroke survivors with known AF.

Prior Anticoagulation and Short- or Long-Term Clinical Outcomes in Ischemic Stroke or Transient Ischemic Attack Patients With Nonvalvular Atrial Fibrillation

Background

We aimed to clarify associations between prior anticoagulation and short‐ or long‐term clinical outcomes in ischemic stroke or transient ischemic attack patients with nonvalvular atrial fibrillation.

Methods and Results

A total of 1189 ischemic stroke or transient ischemic attack patients with nonvalvular atrial fibrillation who were hospitalized within 7 days after onset were analyzed. Of these, 813 patients (68.4%) received no prior anticoagulation, 310 (26.1%) received prior warfarin treatment with an international normalized ratio (INR) <2 on admission, 28 (2.4%) received prior warfarin treatment with an INR ≥2 on admission, and the remaining 38 (3.2%) received prior direct oral anticoagulant treatment. Prior warfarin treatment was associated with a lower risk of death or disability at 3 months compared with no prior anticoagulation (INR <2: adjusted odds ratio: 0.58; 95% CI, 0.42–0.81; P=0.001; INR ≥2: adjusted odds ratio: 0.40; 95% CI, 0.16–0.97; P=0.043) but was not associated with a lower risk of death or disability at 2 years. Prior warfarin treatment with an INR ≥2 on admission was associated with a higher risk of ischemic events within 2 years compared with no prior anticoagulation (adjusted hazard ratio: 2.94; 95% CI, 1.20–6.15; P=0.021).

Conclusions

Prior warfarin treatment was associated with a lower risk of death or disability at 3 months but was not associated with a lower risk of death or disability at 2 years in ischemic stroke or transient ischemic attack patients with nonvalvular atrial fibrillation. Prior warfarin treatment with an INR ≥2 on admission was associated with a higher risk of ischemic events within 2 years.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01581502.

Patients on NOACs in the Emergency Room

PURPOSE OF REVIEW

Despite the increasing use of NOACs, there is still uncertainty on how to treat NOAC patients presenting with neurological emergencies. Initial assessment of coagulation status is challenging but essential in these patients to provide best-possible treatment in case of ischemic or hemorrhagic stroke. Meanwhile, anticoagulation reversal strategies have been suggested; yet, the optimal management is still unestablished. The current review aims to provide up-to-date information on (i) how to identify patients with NOAC intake, (ii) which therapies are feasible in the setting of ischemic and hemorrhagic stroke as well as traumatic intracranial hemorrhage, and (iii) how to proceed with patients requiring emergency lumbar puncture.

RECENT FINDINGS

Despite several expert opinions, there is still an ongoing debate which NOAC patients presenting with ischemic stroke may benefit from recanalizing strategies and whether these treatment approaches can be performed safely. Results from two phase IV trials investigating the efficacy of NOAC-specific reversal agents in case of major bleeding seem promising with regard to hemostatic parameters, but these antidotes have not been verified to clinically benefit patients, and approval by authorities in parts is still pending. Specific reversal agents are on the way and will provide new treatment options in patients with NOAC-related ischemic and hemorrhagic stroke. Up to now, the decision which patients should undergo recanalizing treatment for ischemic stroke, or which specific pharmacological reversal treatment in hemorrhagic stroke should be initiated, has to be made cautiously on an individual basis after assessing hemostatic parameters.

Cerebral Ischemia in Patients on Direct Oral Anticoagulants

Background and Purpose—

In patients with ischemic stroke on therapy with vitamin K antagonists, stroke severity and clinical course are affected by the quality of anticoagulation at the time of stroke onset, but clinical data for patients using direct oral anticoagulants (DOACs) are limited.

Methods—

Data from our registry including all patients admitted with acute cerebral ischemia while taking oral anticoagulants for atrial fibrillation between November 2014 and October 2017 were investigated. The activity of vitamin K antagonists was assessed using the international normalized ratio on admission and categorized according to a threshold of 1.7. DOAC plasma levels were measured using the calibrated Xa-activity (apixaban, rivaroxaban, and edoxaban) or the Hemoclot-assay (dabigatran) and categorized into low (<50 ng/mL), intermediate (50–100 ng/mL), or high (>100 ng/mL). Primary objective was the association between anticoagulant activity and clinical and imaging characteristics.

Results—

Four hundred sixty patients were included (49% on vitamin K antagonists and 51% on DOAC). Patients on vitamin K antagonists with low international normalized ratio values had higher scores on the National Institutes of Health Stroke Scale and a higher risk of large vessel occlusion on admission. For patients on DOAC, plasma levels were available in 75.6% and found to be low in 49 (27.7%), intermediate in 41 (23.2%), and high in 87 patients (49.2%). Low plasma levels were associated with higher National Institutes of Health Stroke Scale scores on admission (low: 8 [interquartile range, 3–15] versus intermediate: 4 [1–11] versus high: 3 [0–8]; P <0.001) and higher risk of persisting neurological deficits or cerebral infarction on imaging (85.7% versus 75.6% versus 54.0%; P <0.001). Low DOAC plasma levels were an independent predictor of large vessel occlusion (odds ratio, 3.84 [95% CI, 1.80–8.20]; P =0.001).

Conclusions—

The activity of anticoagulation measured by specific DOAC plasma levels on admission is associated with stroke severity and presence of large vessel occlusion.

Clinical presentation, diagnostic findings and management of cerebral ischemic events in patients on treatment with non-vitamin K antagonist oral anticoagulants - A systematic review

Background

Non-vitamin K antagonist oral anticoagulants (NOAC) are equally or potentially superior in terms of effectiveness in the prevention of ischemic stroke and carry a lower associated risk of intracranial hemorrhage compared to Vitamin K antagonists. Nevertheless, ischemic strokes also occur in patients who are being treated with NOAC. In those particular patients, knowledge about the underlying stroke etiology, clinical presentation, acute management, and complication rates is scarce.

Objective

Systematic literature review to provide a comprehensive clinical overview in terms of presentation, laboratory, imaging parameters and outcomes of patients suffering from acute cerebral ischemic events (i.e. TIA and acute ischemic stroke) while on treatment with a NOAC. Only if available, comparison to VKA is presented which was not the primary focus of this analysis.

Data sources

PubMed/MEDLINE, Scopus and EMBASE from January 1, 2006, to November 20, 2018.

Study eligibility criteria

52 studies providing detailed information on a total of 12247 patients were included. We excluded case reports and case series with less than five patients.

Study appraisal and synthesis method

We systematically assessed study quality using a bias tool and pooled consistent data.

Results

Existing data indicates milder stroke severity and smaller infarct size of acute ischemic stroke on treatment with NOAC compared to stroke occurrence on Vitamin K antagonists (VKA). Established risk factors for ischemic events also play a role in stroke while on NOACs, albeit the underlying etiology remains poorly understood. Intravenous thrombolysis and endovascular therapy seem to be safe and effective, but patient selection for recanalization therapies is challenging.

Limitations

Limited quality of published data, duplicate cases, statistical issues of data pooling, possible incomplete retrieval of identified research and reporting bias might have limited our findings.

Conclusions

Acute ischemic events despite treatment with NOAC therapy are insufficiently investigated.

Systematic review registration number

PROSPERO: CRD42018074853.

Rationale and design of the Registry of Acute Stroke Under Novel Oral Anticoagulants-prime (RASUNOA-prime)

Background

Anticoagulation with vitamin K antagonists and non-vitamin K antagonists oral anticoagulants (NOAC) is effective in stroke prevention in patients with atrial fibrillation. However, anticoagulation also poses a major challenge for emergency treatment of patients suffering ischaemic stroke or intracerebral haemorrhage.

Aim

The registry RASUNOA-prime is designed to describe current patterns of emergency management, clinical course and outcome of patients with atrial fibrillation experiencing an acute ischaemic stroke or intracerebral haemorrhage under different anticoagulation schemes prior to stroke (NOAC, vitamin K antagonists or no anticoagulation).

Methods and design

RASUNOA-prime (ClinicalTrials.gov, NCT02533960) is a prospective, investigator-initiated, multicentre, observational cohort study aiming to recruit 3000 patients with acute ischaemic stroke and atrial fibrillation, and 1000 patients with acute intracerebral haemorrhage and atrial fibrillation with different anticoagulation schemes pre-stroke. It is a non-interventional triple-armed study aiming at a balanced inclusion of ischaemic stroke and intracerebral haemorrhage patients according to the different anticoagulation schemes. Patients will be followed up for clinical course, management and outcome up to three months after the event. Findings in ischaemic stroke and intracerebral haemorrhage patients on NOAC will be compared with patients taking vitamin K antagonists or no anticoagulant pre-stroke.

Study outcomes

Primary endpoint for ischaemic stroke patients: occurrence of symptomatic intracerebral haemorrhage, for intracerebral haemorrhage patients: occurrence of secondary haematoma expansion. Secondary endpoints include assessment of coagulation, use of thrombolysis and/or mechanical thrombectomy, occurrence of complications, implementation of secondary prevention.

Summary

Describing the current patterns of early management as well as outcome of stroke patients with atrial fibrillation will help guide physicians to develop recommendations for emergency treatment of stroke patients under different anticoagulation schemes.

Detection of Atrial Fibrillation in Cryptogenic Stroke

PURPOSE OF REVIEW

To summarize the literature on the detection of atrial fibrillation (AF) in patients with "cryptogenic" stroke, a cohort including about 25% of all ischemic stroke patients and patients with embolic stroke of undetermined source (ESUS).

RECENT FINDINGS

A first episode of AF is detected in up to one third of cryptogenic stroke and in up to one fourth of ESUS patients during long-term monitoring. AF prevalence correlates to patient selection, duration, and quality of ECG monitoring. Higher rates of AF were reported in stroke patients with left atrial pathology, specific ECG alterations, or increased natriuretic peptides. While AF detection impacts on medical stroke prevention in the vast majority of patients, patient selection for prolonged monitoring is largely left at the physician's discretion. AF detection after cryptogenic stroke or ESUS is a frequent, potentially causal condition. Whether subsequent oral anticoagulation may improve outcome remains open.

Expert opinion paper on atrial fibrillation detection after ischemic stroke

This expert opinion paper on atrial fibrillation detection after ischemic stroke includes a statement of the "Heart and Brain" consortium of the German Cardiac Society and the German Stroke Society. This paper was endorsed by the Stroke Unit-Commission of the German Stroke Society and the German Atrial Fibrillation NETwork. In patients with ischemic stroke, detection of atrial fibrillation should usually lead to a change in secondary stroke prevention, since oral anticoagulation is superior to antiplatelet drugs. The detection of previously undiagnosed atrial fibrillation can be improved in patients with ischemic stroke to optimize stroke prevention. This paper summarizes the present knowledge on atrial fibrillation detection after ischemic stroke. We propose an interdisciplinary standard for a "structured analysis of ECG monitoring" on the stroke unit as well as a staged diagnostic scheme for the detection of atrial fibrillation. Since the optimal duration and mode of ECG monitoring has not yet been finally established, this paper is intended to give advice to physicians who are involved in stroke care. In line with the nature of an expert opinion paper, labeling of classes of recommendations is not provided, since many statements are based on the expert opinion, reported case series and clinical experience. Therefore, this paper is not intended as a guideline.