Anticoagulation Resumption After Stroke from Atrial Fibrillation

Reversal and resumption of anticoagulants in patients with anticoagulant-associated intracerebral hemorrhage

The use of anticoagulants has become more frequent due to the progressive aging population and increased thromboembolic events. Consequently, the proportion of anticoagulant-associated intracerebral hemorrhage (AAICH) in stroke patients is gradually increasing. Compared with intracerebral hemorrhage (ICH) patients without coagulopathy, patients with AAICH may have larger hematomas, worse prognoses, and higher mortality. Given the need for anticoagulant reversal and resumption, the management of AAICH differs from that of conventional medical or surgical treatments for ICH, and it is more specific. Understanding the pharmacology of anticoagulants and identifying agents that can reverse their effects in the early stages are crucial for treating life-threatening AAICH. When patients transition beyond the acute phase and their vital signs stabilize, it is important to consider resuming anticoagulants at the right time to prevent the occurrence of further thromboembolism. However, the timing and strategy for reversing and resuming anticoagulants are still in a dilemma. Herein, we summarize the important clinical studies, reviews, and related guidelines published in the past few years that focus on the reversal and resumption of anticoagulants in AAICH patients to help implement decisive diagnosis and treatment strategies in the clinical setting.

Electrocardiogram prediction of atrial fibrillation risk after stroke: A protocol for systematic review and meta-analysis

BACKGROUND

Atrial fibrillation (AF) is one of the most common clinical arrhythmias. This study aims to predict the risk of post-stroke AF through electrocardiographic changes in sinus rhythm.

METHODS

We searched the MEDLINE (PubMed) and EMBASE databases to identify relevant research articles published until August 2023. Prioritized items from systematic reviews and meta-analyses were screened, and data related to AF detection rate were extracted. A meta-analysis using a random-effects model was conducted for data synthesis and analysis.

RESULTS

A total of 32 studies involving electrocardiograms (ECG) were included, with a total analysis population of 330,284 individuals. Among them, 16,662 individuals (ECG abnormal group) developed AF, while 313,622 individuals (ECG normal group) did not. ECG patterns included terminal P-wave terminal force V1, interatrial block (IAB), advanced interatrial block, abnormal P-wave axis, pulse rate prolongation, and atrial premature complexes. Overall, 15,762 patients experienced AF during the study period (4.77%). In the ECG abnormal group, the proportion was 14.21% (2367/16,662), while in the control group (ECG normal group), the proportion was 4.27% (13,395/313,622). The pooled risk ratio for developing AF was 2.45 (95% confidence interval [CI]: 2.02-2.98, P < .001), with heterogeneity (I2) of 95%. The risk ratio values of alAB, P-wave terminal force V1, interatrial block, abnormal P-wave axis, pulse rate prolongation and atrial premature complexes were 4.12 (95% CI, 2.99-5.66), 1.47 (95% CI, 1.19-1.82), 2.54 (95% CI, 1.83-3.52), 1.70 (95% CI, 0.98-2.97), 2.65 (95% CI, 1.88-3.72), 3.79 (95% CI, 2.12-6.76), respectively.

CONCLUSION

There is a significant correlation between ECG patterns and the occurrence of AF. The alAB exhibited the highest level of predictability for the occurrence of AF. These indicators support their use as screening tools to identify high-risk individuals who may benefit from further examinations or empirical anticoagulation therapy following stroke.

Current and Emerging Endovascular and Neurocritical Care Management Strategies in Large-Core Ischemic Stroke

The volume of infarcted tissue in patients with ischemic stroke is consistently associated with increased morbidity and mortality. Initial studies of endovascular thrombectomy for large-vessel occlusion excluded patients with established large-core infarcts, even when large volumes of salvageable brain tissue were present, due to the high risk of hemorrhagic transformation and reperfusion injury. However, recent retrospective and prospective studies have shown improved outcomes with endovascular thrombectomy, and several clinical trials were recently published to evaluate the efficacy of endovascular management of patients presenting with large-core infarcts. With or without thrombectomy, patients with large-core infarcts remain at high risk of in-hospital complications such as hemorrhagic transformation, malignant cerebral edema, seizures, and others. Expert neurocritical care management is necessary to optimize blood pressure control, mitigate secondary brain injury, manage cerebral edema and elevated intracranial pressure, and implement various neuroprotective measures. Herein, we present an overview of the current and emerging evidence pertaining to endovascular treatment for large-core infarcts, recent advances in neurocritical care strategies, and their impact on optimizing patient outcomes.

Contemporary Antiplatelet and Anticoagulant Therapies for Secondary Stroke Prevention: A Narrative Review of Current Literature and Guidelines

PURPOSE OF REVIEW

Stroke is a leading cause of death and disability worldwide. The annual incidence of new or recurrent stroke is approximately 795,000 cases per year in the United States, of which 87% are ischemic in nature. In addition to the management of modifiable high-risk factors to reduce the risk of recurrent stroke, antithrombotic agents (antiplatelets and anticoagulants) play an important role in secondary stroke prevention. This review will discuss the published literature on the use of antiplatelets and anticoagulants in secondary prevention of acute ischemic stroke and transient ischemic attack (TIA), including their pharmacology, efficacy, and adverse effects. We will also highlight the role of dual antiplatelet therapy (DAPT) in secondary stroke prevention, along with supporting literature.

RECENT FINDINGS

Single antiplatelet therapy (SAPT) with aspirin or clopidogrel reduces the risk of recurrent ischemic stroke in patients with non-cardioembolic ischemic stroke or TIA. However, as shown in recent trials, short-term DAPT with aspirin and clopidogrel or ticagrelor for 21-30 days is more effective than SAPT in patients with minor acute non-cardioembolic stroke or high-risk TIA. Although short-term DAPT is highly effective in preventing recurrent stroke, a more prolonged course can increase bleeding risks without additional benefit. DAPT for 90 days, followed by aspirin monotherapy for patients with large vessel intracranial atherosclerotic disease, is suitable for secondary stroke prevention. However, patients need to be monitored for both minor (e.g., bruising) and major (e.g., intracranial) bleeding complications. Conversely, oral warfarin and newer direct oral anticoagulant (DOACs) such as dabigatran, rivaroxaban, apixaban, and edoxaban are the agents of choice for secondary stroke prevention in patients with non-valvular cardioembolic strokes. DOACs may be preferred over warfarin due to decreased bleeding risks, including ICH, lack of need for international normalized ratio monitoring, no dietary restrictions, and limited drug-drug interactions. The choice between different antiplatelets and anticoagulants for prevention of ischemic stroke depends on the underlying stroke mechanism, cytochrome P450 2C19 polymorphisms, bleeding risk profile, compliance, drug tolerance, and drug resistance. Physicians must carefully weigh each patient's relative benefits and bleeding risks before initiating an antiplatelet/anticoagulant treatment regimen. Further studies are warranted to study the optimal duration of DAPT in symptomatic intracranial atherosclerosis since the benefit is most pronounced in the short term while the bleeding risk remains high during the extended duration of therapy.

Hemorrhagic Conversion of Acute Ischemic Stroke

Stroke is a leading cause of morbidity and mortality worldwide; a serious complication of ischemic stroke is hemorrhagic transformation. Current treatment of acute ischemic stroke includes endovascular thrombectomy and thrombolytic therapy. Both of these treatment options are linked with increased risks of hemorrhagic conversion. The diagnosis and timely management of patients with hemorrhagic conversion is critically important to patient outcomes. This review aims to discuss hemorrhagic conversion of acute ischemic stroke including discussion of the pathophysiology, review of risk factors, imaging considerations, and treatment of patients with hemorrhagic conversion.

The optimum anticoagulation time after endovascular thrombectomy for atrial fibrillation-related large vessel occlusion stroke: a real-world study

OBJECTIVES

To investigate the relationship between the initiation time of anticoagulation after endovascular treatment (EVT) and the outcomes in atrial fibrillation (AF)-related acute ischemic stroke (AIS) patients.

METHODS

In this prospective registry study, from March 2013 to June 2022, patients with anterior circulation territories AF-related AIS who underwent EVT within 24 h were included. The primary outcome was favorable [modified Rankin Scale (mRS) 0-1) at ninety days and the secondary outcome was hemorrhage events after anticoagulants. Factors affecting the outcomes were pooled into multivariate regression and ROC curve analysis.

RESULTS

Of 234 eligible patients, there were 63 (26.9%) patients achieved a favorable outcome. The symptomatic intracranial hemorrhage (sICH), ICH, and systemic hemorrhage events after anticoagulants occurred in 8 (3.4%), 28 (12.0%), and 39 (16.7%) patients, severally. A longer EVT to anticoagulation time (p = 0.033) was associated with an unfavorable outcome (mRS 3-6). An earlier EVT to anticoagulation time was the independent risk factor of sICH (p = 0.043), ICH (p = 0.005), and systemic hemorrhage (p = 0.005). There was no significant difference in recurrent AIS/ transient ischemic attack (TIA) or mortality among patients who started anticoagulation at ≤ 4 days, ≥ 15 days, or 4 to 15 days. The optimum cut-off for initiating anticoagulants to predict a favorable outcome and hemorrhage events was 4.5 days and 3.5 days after EVT, respectively.

CONCLUSIONS

In AF-related AIS, the time of EVT to anticoagulation is an independent factor of the functional outcome and hemorrhage events after anticoagulation. The optimal initiate time of anticoagulant after EVT is 4.5 days.

CLINICALTRIALREGISTER

NCT03754738.

Successful Mechanical Thrombectomy of Bilateral Middle Cerebral Artery Occlusions Following Apixaban Discontinuation

Optimal anticoagulation management in patients with atrial fibrillation (AF) during acute ischemic stroke is complex and often poses a significant clinical challenge. An 82-year-old man with AF presented with left-sided hemiparesis and hypoesthesia due to occlusion of the right middle cerebral artery (MCA) after discontinuing apixaban for 5 days. Successful mechanical thrombectomy (MT) achieved thrombolysis in cerebral infarction (TICI) score of 2C. Anticoagulation was postponed due to a small risk of hemorrhagic conversion. However, the patient developed a rare bilateral M1 segment MCA occlusions on the fifth day with a National Institute of Health Stroke Scale (NIHSS) score of 23, leading to an emergent thrombectomy, resulting in TICI 3 and TICI 2C recanalization in left and right MCAs, respectively. The patient required admission to the intensive care unit and was eventually discharged to an inpatient rehabilitation facility with only residual left hemiparesis and moderate dysarthria. This case underscores the delicate balance between the risk of recurrent ischemic stroke and the potential for hemorrhagic conversion when treating anticoagulation in the acute setting. Close monitoring and an individualized approach are necessary for the treatment of patients with AF who have suffered an acute stroke, especially when anticoagulation must be stopped. We encourage future guidelines to incorporate both imaging and clinical data when determining the continuation of anticoagulation in patients with a recent ischemic stroke. This case also depicts the effectiveness of neuroendovascular interventions such as MT to effectively manage rare simultaneous large multi-vessel occlusions with good outcomes.

Acute Stroke and Atrial Fibrillation: Risk of Incorrect NOAC Dosage When Estimating Renal Function From Plasma Creatinine Only

Background

Cardioembolic stroke (CS) due to atrial fibrillation (AF) bears a high risk of unfavorable outcome. Treatment with a non-vitamin K antagonist oral anticoagulant (NOAC) reduces this risk. NOAC dosage occurs on a thin line during the acute phase of the stroke unit when the patient is threatened by both recurrent CS and a hemorrhagic stroke. It is often adapted to renal function—usually glomerular filtration rate (GFR)—to prevent both under- and overdosing. This study investigates the hypothetical risk of incorrect NOAC dosage after acute stroke when relying on plasma creatinine alone in comparison to a more exact renal function assessment including urine collection.

Methods

In a cohort study on consecutive 481 patients treated in a stroke unit with acute stroke and AF, the GFR estimated from plasma creatinine (eGFR) was compared to concurrent creatinine clearance measurement (CrCl) from urine collection regarding the hypothetically derived NOAC dosage.

Results

The risk of incorrect dosage (mean, 95% confidence interval) was 6.9% (4.8–9.5), 26% (23–31), 38% (33–42), and 20% (16–23) for apixaban, dabigatran, edoxaban, and rivaroxaban, respectively. The overall risk for incorrect dosage of any NOAC was 23% (21–25). Thresholds for age and admission eGFR were optimized to achieve an overall risk below 5% by additional CrCl measurements in selected patients (apixaban <36 ml/min and any age, dabigatran <75 ml/min and >70 y, edoxaban >36 ml/min and >58 y, rivaroxaban <76 ml/min and >75 y, any NOAC <81 ml/min and >54 y). The resulting portion of patients requiring an additional CrCl measurement was 10, 60, 80, 55, and 65% for apixaban, dabigatran, edoxaban, rivaroxaban, and any NOAC, respectively.

Conclusions

There is a considerable risk of incorrect NOAC dosage in patients with acute CS treated in a stroke unit that can be lowered by targeted CrCl measurements in selected patients.

Antithrombotic dilemmas in stroke medicine: new data, unsolved challenges

Antithrombotic therapy is a key element of secondary prevention in patients who have had an ischaemic stroke or transient ischaemic attack. However, its use in clinical practice is not always straightforward. This review provides an update on certain difficult scenarios in antithrombotic management, with a focus on recent clinical trials and large observational studies. We discuss the approach to patients with an indication for antithrombotic treatment who also have clinical or radiological evidence of previous intracranial bleeding, patients with indications for both anticoagulant and antiplatelet treatment, and patients in whom antithrombotic treatment fails to prevent stroke. We also review the timing of anticoagulation initiation after cardioembolic stroke, and the use of antithrombotics in patients with asymptomatic cerebrovascular disease. Despite a wealth of new evidence, numerous uncertainties remain and we highlight ongoing trials addressing these.

Anticoagulation and Stroke

In 2019, the American Heart Association did not recommend the emergent use of anticoagulation to prevent recurrence or progression of acute ischemic stroke. However, its indication in patients with extracranial artery intraluminal thrombus with artery-to-artery cerebral embolization must be analyzed. In this article, we will also discuss other indications of anticoagulation. This treatment could be indicated in patients with ischemic stroke caused by embolization from cervical artery dissection, catastrophic antiphospholipid antibodies syndrome (APS) and some cases of Covid 19. For secondary prevention, anticoagulation is recommended for Cardioembolic stroke such as nonvalvular atrial fibrillation and other cardiopathies, some patients with cervical artery dissection, stroke associated with cancer, and thrombophilia such as APS. The timing to restart anticoagulation after a large ischemic stroke or after a cerebral hemorrhagic transformation always represent a challenge. Even in patients with high risk of thromboembolism it should be delayed at least two weeks, ideal after four weeks.

Rationale, Design and Methods of the Prospective Record of the Use of Dabigatran in Patients with Acute Stroke or TIA (PRODAST) Study

Background

The optimal timing of anticoagulation following acute ischaemic stroke or TIA in patients with atrial fibrillation (AF) is a frequent challenge. Early initiation of anticoagulation can reduce the risk for recurrent ischaemic events, but may lead to an increased risk for intracerebral haemorrhage.

Aim

The Prospective Record of the Use of Dabigatran in Patients with Acute Stroke or TIA (PRODAST) study was initiated to investigate outcome events under antithrombotic therapy after ischaemic stroke or TIA in patients with AF. The main objective is to compare the three-month rates of major haemorrhagic events between early (≤ 7 days) versus late (> 7 days) administration of dabigatran or treatment with vitamin-K antagonists started at any time. Occurrences of ischaemic and major haemorrhagic events will be evaluated to determine the optimal time point for initiation or resumption of anticoagulation.

Design and Methods

PRODAST is a prospective, multicenter, observational, non-interventional post-authorization safety study. 10,000 patients with recent (≤ 1 week from index event) ischaemic stroke or TIA and non-valvular AF were recruited at 86 German sites starting in July 2015. The observational plan includes a baseline visit, documentation of data during hospitalization and a telephone-based, central follow-up at three months after the index event. The primary endpoint is the major bleeding rate within three months. Secondary endpoints include rates of recurrent ischaemic or haemorrhagic stroke, TIA, systemic embolism, myocardial infarction and death.

Summary

PRODAST will provide important real-world data on safety and efficacy of antithrombotic therapy after acute stroke and TIA in patients with AF.

Bi-atrial thrombus straddling a patent foramen ovale with bilateral embolization: A therapeutic challenge

Stroke is a leading cause of morbidity and mortality across the world and a significant portion of ischemic strokes have a cardiac source. We report a case of a 55-year-old male who presented with an ischemic stroke and bilateral pulmonary emboli secondary to an intra-cardiac thrombus straddling a patent foramen ovale, which was clearly seen using transesophageal echocardiography. We discuss the management dilemma associated with this clinical picture given the risk of hemorrhagic transformation in the acute phase of an ischemic stroke. Our case demonstrates the need for a multidisciplinary approach in an area of medicine that lacks clear guidelines.

Difficult issues in the management of patients with atrial fibrillation: a neurologist's point of view

The article evaluates recent perspectives about the role of oral anticoagulants in the secondary prevention of cardioembolic stroke. The timing of prescribing drugs for ischemic stroke and transient ischemic attack is discussed in accordance with current clinical guidelines and the results of clinical trials. The issues of prescribing oral anticoagulants in some problematic situations, such as the elderly and senile age, reperfusion therapy, presence of hemorrhagic transformation, combined atherosclerosis of major head and neck arteries, cerebral microangiopathy, history of intracerebral hemorrhage, cryptogenic stroke, and low patient compliance are considered. Finally, an anticoagulant therapy algorithm in the acute period of cardioembolic stroke is presented.

Early anticoagulation in atrial fibrillation-related acute ischaemic stroke: efficacy and safety profile

OBJECTIVES

To evaluate the effects of early anticoagulation on functional outcome, recurrent ischaemic events and haemorrhagic complications in Atrial Fibrillation (AF)-related acute ischaemic strokes (AIS).

MATERIALS AND METHODS

We retrospectively evaluated patients hospitalised in a Stroke Unit due to AF-related AIS. Patients were divided according to anticoagulation initiation timing (0-4 days, 5-14 days, no anticoagulation by the 14th day). We assessed the following outcomes at 3 months: favourable functional outcome [modified Rankin Scale (mRS) score 0-2 or equal to pre-stroke], recurrent ischaemic events and haemorrhagic complications after anticoagulation initiation.

RESULTS

We included 395 patients. Anticoagulation was initiated at days 0-4 in 33.9% of patients, days 5-14 in 25.3% and not initiated by the day 14 in 40.8%. Factors associated with earlier anticoagulation included lower previous mRS, valvular AF and lower stroke severity. Favourable functional outcome occurred in 40.2% of patients, with lower odds in those anticoagulated at 5-14 versus 0-4 days (OR: 0.47, 95% CI: 0.23-0.94), independently of age, previous mRS and stroke severity. Recurrent ischaemic events occurred in 8.3% of patients, with higher odds in non-anticoagulated patients by the 14th day, compared to the remainder groups (OR: 3.26, 95% CI: 1.29-8.22 vs. 0-4 days and OR: 8.16, 95% CI: 1.76-37.9 vs. 5-14 days). In patients who started anticoagulation (n = 288), haemorrhagic complications occurred in 10.8%, being more frequent in those who started at 0-4 days vs. > 14 days. However, it did not abolish the 0-4-day initiation's benefit on functional outcome.

CONCLUSIONS

Early anticoagulation was associated with lower ischaemic recurrence and better functional outcome at 3 months. Additional studies are needed to better clarify its haemorrhagic risk.

Anticoagulation After Ischemic Stroke or Transient Ischemic Attack (TIA) in the Time of Direct Oral Anticoagulation (DOAC) and Thrombectomy

Objective To assess anticoagulation (AC) timing and appropriateness in patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA) due to atrial fibrillation (AF) in a predominantly Hispanic community hospital in the era of direct oral AC (DOAC) and endovascular thrombectomy (EVT). Methods Adult patients presenting with known or new-onset AF and primary diagnosis of AIS/TIA admitted to Baptist Hospital of Miami between January 2018 and January 2019 were included. AC appropriateness was determined on medical history and concordance with American Heart Association AHA/American Stroke Association (ASA) AC guidelines. Median time from AIS/TIA diagnosis to AC initiation was the primary endpoint. AC guideline concordance on admission and at discharge, discordant justification, and AC selection were secondary endpoints. Results The sample included 120 patients. AC initiation was five days (interquartile range (IQR) 2-9) following AIS/TIA. Patients' receiving intravenous (IV) alteplase experienced a 1.4-day delay in AC initiation (x̅=5.44, SE=1.05, p<.05). There was no significant delay for those receiving EVT. A symptomatic hemorrhagic transformation occurred in 3% (n=3) of patients; only one patient was initiated on AC prior to the event. No recurrent AIS/TIAs occurred prior to discharge. Guideline-based AC concordance increased by 14% to 96% from admission to discharge. Apixaban (78%, n=52) was the most prescribed anticoagulant during hospitalization. Discussion This study suggests that early AC initiation for patients with AF and AIS/TIA with or without IV alteplase and/or EVT is a safe and effective stroke prevention intervention. Further, it identified a need for improved concordance with guideline-based AC within the clinic setting.

Quantifying the Impact of Comorbidities on Outcomes Following Surgery for Osteoporotic Vertebral Compression Fractures

Introduction Studies have shown that osteoporotic patients are more likely to have medical or surgical complications postoperatively. In this study, we determine the predictive value of various comorbidities on the likelihood of postoperative complications, mortality, and 30-day readmission following cement augmentation for osteoporotic vertebral compression fractures (OVCFs).

Materials and Methods A retrospective analysis of the American College of Surgeons National Surgery Quality Improvement Project (ACS-NSQIP) database from 2007 to 2014 identified 1979 patients who met inclusion criteria. A multivariate logistic regression analysis was utilized to determine the relationship between various comorbidities and perioperative mortality, postoperative complications, and 30-day readmission rates.

Results A history of cerebrovascular accident (CVA), coagulopathy, diminished preoperative functional status, and/or an American Society of Anesthesiologists (ASA) class > 2 were statistical predictors of postoperative complications. CVA generated the highest odds ratio among these comorbidities (OR = 5.36, p = 0.02 for minor complications; OR = 4.60 p = 0.05 for major complications). Among the 15 comorbidities considered, steroid use (OR =1.81; p = 0.03) and an ASA class > 2 (OR = 14.65; p = 0.01) were the only ones that were correlated with mortality; an ASA class > 2 had a particularly strong effect on the likelihood of mortality (OR = 14.65). Chronic obstructive pulmonary disorder (COPD), obesity, significant weight loss, and an ASA class > 2 were correlated with 30-day readmissions. Congestive heart failure (CHF), diabetes, dialysis, hypertension, or smoking was not correlated with adverse postoperative outcomes.

Conclusion Of the 15 comorbidities considered in this study, four were statistically associated with increased rates of postoperative complications, two were associated with increased mortality, and four were associated with increased rates of readmission at 30 days. The presence of CHF, diabetes mellitus (DM), hypertension, ascites, renal failure, or smoking were not associated with the adverse outcomes studied.

Level of Evidence III.

Atrial Fibrillation and Ischemic Stroke: A Clinical Review

Atrial fibrillation (AF) is an important risk factor for ischemic stroke resulting in a fivefold increased stroke risk and a twofold increased mortality. Our understanding of stroke mechanisms in AF has evolved since the concept of atrial cardiopathy was introduced as an underlying pathological change, with both AF and thromboembolism being common manifestations and outcomes. Despite the strong association with stroke, there is no evidence that screening for AF in asymptomatic patients improves clinical outcomes; however, there is strong evidence that patients with embolic stroke of undetermined source may require long-term monitoring to detect silent or paroxysmal AF. Stroke prevention in patients at risk, assessed by the CHA₂DS₂-VASc score, was traditionally achieved with warfarin; however, direct oral anticoagulants have solidified their role as safe and effective alternatives. Additionally, left atrial appendage exclusion has emerged as a viable option in patients intolerant of anticoagulation. When patients with AF have an acute stroke, the timing of initiation or resumption of anticoagulation for secondary stroke prevention has to be balanced against the risk of hemorrhagic conversion. Multiple randomized clinical trials are currently underway to determine the best timing for administration of anticoagulants following acute ischemic stroke.

Management of Intracerebral Hemorrhage: JACC Focus Seminar

Intracerebral hemorrhage (ICH) accounts for a disproportionate amount of stroke-related morbidity and mortality. Although chronic hypertension and cerebral amyloid angiopathy are the underlying cerebral vasculopathies accounting for the majority of ICH, there are a broad range of potential causes, and effective management requires accurate identification and treatment of the underlying mechanism of hemorrhage. Magnetic resonance imaging and vascular imaging techniques play a critical role in identifying disease mechanisms. Modern treatment of ICH focuses on rapid stabilization, often requiring urgent treatment of mass effect, aggressive blood pressure reduction and correction of contributing coagulopathies to achieve hemostasis. We discuss management of patients with ICH who continue to require long-term anticoagulation, the interaction of ICH with neurodegenerative diseases, and our approach to prognostication after ICH. We close this review with a discussion of novel medical and surgical approaches to ICH treatment that are being tested in clinical trials.

Anticoagulation Timing in Cardioembolic Stroke and Recurrent Event Risk

OBJECTIVE

Guidelines recommend initiating anticoagulation within 4 to 14 days after cardioembolic stroke. Data supporting this did not account for key factors potentially affecting the decision to initiate anticoagulation, such as infarct size, hemorrhagic transformation, or high-risk features on echocardiography.

METHODS

We pooled data from stroke registries of 8 comprehensive stroke centers across the United States. We included consecutive patients admitted with ischemic stroke and atrial fibrillation. The primary predictor was timing of initiating anticoagulation (0-3 days, 4-14 days, or >14 days), and outcomes were recurrent stroke/transient ischemic attack/systemic embolism, symptomatic intracerebral hemorrhage (sICH), and major extracranial hemorrhage (ECH) within 90 days.

RESULTS

Among 2,084 patients, 1,289 met the inclusion criteria. The combined endpoint occurred in 10.1% (n = 130) subjects (87 ischemic events, 20 sICH, and 29 ECH). Overall, there was no significant difference in the composite endpoint between the 3 groups (0-3 days: 10.3%, 64/617; 4-14 days: 9.7%, 52/535; >14 days: 10.2%, 14/137; p = 0.933). In adjusted models, patients started on anticoagulation between 4 and 14 days did not have a lower rate of sICH (vs 0-3 days; odds ratio [OR] = 1.49, 95% confidence interval [CI] = 0.50-4.43), nor did they have a lower rate of recurrent ischemic events (vs >14 days; OR = 0.76, 95% CI = 0.36-1.62, p = 0.482).

INTERPRETATION

In this multicenter real-world cohort, the recommended (4-14 days) time frame to start oral anticoagulation was not associated with reduced ischemic and hemorrhagic outcomes. Randomized trials are required to determine the optimal timing of anticoagulation initiation. ANN NEUROL 2020;88:807-816.

Timing of Initiation of Oral Anticoagulation after Acute Ischemic Stroke in Patients with Atrial Fibrillation

Patients with atrial fibrillation (AF) who suffer an acute ischemic stroke are at risk for both hemorrhagic transformation and recurrent ischemic stroke in the acute post-stroke period. Oral anticoagulants are recommended for secondary stroke prevention in patients with AF. The optimal time to initiate anticoagulant therapy after acute ischemic stroke in patients with AF is uncertain. There is concern that early initiation increases the risk of hemorrhagic transformation, whereas delayed initiation leaves the patient at risk for recurrent ischemic stroke. In this article, we provide a review of the risk of hemorrhagic transformation of acute ischemic stroke as well as review the literature and major guidelines addressing the timing of anticoagulation initiation after an acute ischemic stroke in patients with AF. Relevant articles published from 1990 to the present were identified using the PubMed and Embase databases. The majority of available literature is observational data. Large ischemic lesions, cerebral microbleeds, thrombolytic therapy, and other clinical factors may increase the risk of hemorrhagic transformation of an acute ischemic stroke. Parenteral anticoagulation within 48 hours is associated with an increased risk of hemorrhagic transformation and is not recommended. Insufficient data exist to support the safety of routine oral anticoagulant (direct oral anticoagulants or warfarin) initiation within 48 hours of an acute ischemic stroke. Direct oral anticoagulant initiation within 2 days of an acute ischemic stroke is associated with a 5% rate of hemorrhagic transformation. Infarct size and presence of hemorrhage are important factors in identifying the optimal time to initiation and should guide decisions when available. A recommended framework for patient decision making is provided. Randomized controlled trials in this area are needed to identify the optimal timing of anticoagulation initiation, and such trials are under way.