Intracerebral haemorrhage in patients taking different types of oral anticoagulants: a pooled individual patient data analysis from two national stroke registries

Thromboelastography may assess the effect of anticoagulation reversal in intracranial hemorrhage

BACKGROUND

Intracranial hemorrhage (ICH) is a complication of oral anticoagulation and is associated with significant morbidity and mortality. Clinical need exists for biomarkers to measure anticoagulation in patients with factor Xa inhibitor-associated ICH to assess the hemostatic effect of reversal agents. This study explored the utility of thromboelastography (TEG) to assess anticoagulation in emergency department (ED) patients who received activated prothrombin complex concentrate (aPCC) reversal for factor Xa-inhibitor-associated ICH.

METHODS

This was a prospective, single-center, cohort study in a convenient sample of adult patients presenting to the ED with acute factor Xa-associated ICH. Exclusion criteria included pregnancy, incarceration, polytrauma, hepatic failure, or other known coagulopathic conditions. TEG samples were collected prior to anticoagulation reversal, as well as at 30-minutes, 12-hours, and 24-hours post-reversal. Only patients who received aPCC reversal were included in the final analysis.

RESULTS

Pre-reversal TEG was collected on 10 participants prior to aPCC administration. A significant decrease in TEG R-time was observed at 30 minutes post-aPCC reversal (Beta = -0.91, p = 0.035). R-time increased at 12- and 24-hours post-aPCC reversal to baseline levels. Significant changes were not observed in K-time, clot strength, maximum amplitude, or coagulation index.

CONCLUSIONS

TEG R-time decreases acutely after anticoagulation reversal with aPCC and rebounds at 12- and 24-hours post-reversal. TEG R-time may serve as a potential sensitive biomarker of the residual anticoagulation activity of factor Xa inhibitors in patients with ICH that undergo anticoagulation reversal with aPCCs.

Association of oral anticoagulants with risk of brain haemorrhage expansion compared to no-anticoagulation

BACKGROUND

The impact of direct oral anticoagulants (DOAC) on haematoma size after intracerebral haemorrhage (ICH) compared to no-anticoagulation is controversial and prospective data are lacking.

METHODS

The investigator-initiated, multicentre, prospective RASUNOA-prime study enrolled patients with non-traumatic ICH and atrial fibrillation while on a DOAC, vitamin K antagonist (VKA) or no anticoagulation (non-OAC). Neuroimaging was reviewed centrally blinded to group allocation. Primary endpoint was haematoma expansion (≥ 6.5 ml or ≥ 33%, any new intraventricular blood or an increase in modified Graeb score by ≥ 2 points) between baseline and follow-up scan within 72 h after symptom onset.

RESULTS

Of 1,440 patients screened, 951 patients with ICH symptom onset less than 24 h before admission were enrolled. Baseline scans were performed at a median of 2 h (IQR 1-6) after symptom onset. Neurological deficit and median baseline haematoma volumes (11 ml; IQR 4-39) did not differ among 577 DOAC, 251 VKA and 123 non-OAC patients. Haematoma expansion was observed in DOAC patients in 142/356 (39.9, 95%-CI 34.8-45.0%), VKA in 47/155 (30.3, 95-CI 23.1%-37.6%), versus non-OAC in 22/74 (29.7, 19.3-40.1%). Unspecific reversal agents in DOAC-ICH (212/356, 59.6%) did not affect the haematoma expansion rate compared to no-antagonization.

CONCLUSION

Baseline haematoma volume and risk of haematoma expansion did not differ statistically significantly in patients with and without DOAC.

[Correction of the effect of direct oral and parenteral anticoagulants in hemorrhagic stroke]

BACKGROUND

Hemorrhagic stroke is associated with high risk of adverse outcome and follows intake of anticoagulants and antiplatelet agents in 25% of cases. The latest clinical guidelines of the Neurocritical Care Society for correction (reversal) of the effect of anticoagulants and antiplatelet agents in hemorrhagic stroke were published in 2016.

MATERIAL AND METHODS

In accordance with PRISMA recommendations, we reviewed the PubMed, eLibrary and UpToDate databases to a depth of 5 years and selected 48 articles.

RESULTS AND DISCUSSION

Direct oral anticoagulants are currently common. To reverse their effect, one can use specific antidotes (idarucizumab is recommended for dabigatran, andexanet alfa (not yet registered In Russia) for factor Xa inhibitors (rivaroxaban, apixaban)) and combination of prothrombin complex concentrate and tranexamic acid. Protamine sulfate is antidote for unfractionated and low molecular weight heparins. Protamine sulfate completely inactivates unfractionated heparin, but it is less effective against low molecular weight heparin. It is characterized by high probability of anaphylactic reactions, especially after repeated administrations. The effectiveness of andexanet alpha and activated factor VII for reversing the effect of low molecular weight heparin is being studied. Fondaparinux sodium is used for heparin-induced thrombocytopenia. Protamine sulfate is ineffective for reversing the effect of fondaparinux. One can use prothrombin complex concentrate and andexanet alpha, but their effectiveness is unclear. Ciraparantag is being studied in clinical trials. Apparently, ciraparantag is highly effective as an antidote for various anticoagulants.

CONCLUSION

Early hemostatic therapy and reversal of anticoagulant effects in patients with hemorrhagic stroke significantly reduce the risk of adverse outcomes. This problem is being studied. Regular literature review with creation of updated clinical guidelines is needed.

Recent and future advances in intracerebral hemorrhage

Spontaneous intracerebral hemorrhage (ICH) is defined by the rupture of a cerebral blood vessel and the entry of blood into the brain parenchyma. With a global incidence of around 3.5 million, ICH accounts for almost 30 % of all new strokes worldwide. It is also the deadliest form of acute stroke and survivors are at risk of poor functional outcome. The pathophysiology of ICH is a dynamic process with key stages occurring at successive times: vessel rupture and initial bleeding; hematoma expansion, mechanical mass effect and secondary brain injury (peri-hematomal edema). While deep perforating vasculopathy and cerebral amyloid angiopathy are responsible for 80 % of ICH, a prompt diagnostic work-up, including advanced imaging is require to exclude a treatable cause. ICH is a neurological emergency and simple therapeutic measures such as blood pressure lowering and anticoagulant reversal should be implemented as early as possible as part of a bundle of care. Although ICH is still devoided of specific treatment, recent advances give hope for a cautious optimism. Therapeutic approaches under the scope are focusing on fighting against hemorrhage expansion, promoting hematoma evacuation by minimally invasive surgery, and reducing secondary brain injury. Among survivors, the global vascular risk is now better established, but optimal secondary prevention is still unclear and is based on an individual benefit-risk balance evaluation.

Oral anticoagulants-induced intracranial hemorrhage: a real-world pharmacovigilance study over 2008-2024

BACKGROUND

This study aims to review and describe the national post-market cases of oral anticoagulants (OACs)-induced intracranial hemorrhage (ICH) to enhance patient safety.

RESEARCH DESIGN AND METHODS

All ICH cases of OACs as primary suspected medicines were extracted from the FAERS. The disproportionality analysis was utilized for signal detection. Subgroup analyses and logistic regression were conducted according to age, sex, weight, hypertension status, concomitant antiplatelet drugs, and indications. Stratification analysis was performed according to the ICH locations.

RESULTS

In total 11,201 cases of OACs-induced ICH were identified from 2008Q1 to 2024Q1. The median time-to-onset (TTO) and median age for OAC-induced ICHs were 181 days and 75 years, respectively. Most potent positive signal was subdural hemorrhage in rivaroxaban and vitamin K antagonists (VKAs), spinal cord hemorrhage in apixaban, hemorrhagic cerebellar infarction in edoxaban and extra-axial hemorrhage in dabigatran (IC025: 4.04, 5.00, 3.45, 6.09 and 3.51, respectively). After adjusting for confounding factors, lower ICH risks were observed in direct oral anticoagulants (DOACs), compared to VKAs.

CONCLUSION

DOACs demonstrated a robust lower risk of ICH compared with VKAs. Different OACs exhibited distinct risk profiles at different ICH sites. The majority of DOACs-induced ICH occurred within 5 months and in elderly patients.

Association of Prior Antithrombotic Drug Use with 90-Day Mortality After Intracerebral Hemorrhage

Purpose

To estimate the strength of association between use of antithrombotics (AT) drugs with survival after spontaneous intracerebral hemorrhage (s-ICH) comparing oral anticoagulant (OAC) or platelet antiaggregants (PA) with no AT use and in active comparator analyses OAC vs PA, direct oral anticoagulant (DOAC) vs vitamin K antagonist (VKA), and clopidogrel vs aspirin.

Patients and Methods

We identified patients ≥55 years with a first-ever s-ICH between 2015 and 2018 in Southern Denmark (population 1.2 million). From this population, patients who had used an AT at the time of ICH were identified and classified as OAC or PA vs no AT (reference group), and for active comparator analyses as OAC vs PA (reference group), DOAC vs VKA (reference group), or clopidogrel vs aspirin (reference group). We calculated adjusted relative risks (aRRs) and corresponding [95% confidence intervals] for 90-day all-cause mortality with adjustments for potential confounders.

Results

Among 1043 patients who had s-ICH, 206 had used an OAC, 270 a PA, and 428 had no AT use. The adjusted 90-day mortality was higher in OAC- (aRR 1.68 [1.39-2.02]) and PA-users (aRR 1.21 [1.03-1.42]), compared with no AT. Mortality was higher in OAC- (aRR 1.19 [1.05-1.36]) vs PA-users. In analyses by antithrombotic drug type, 88 used a DOAC, 136 a VKA, 111 clopidogrel, and 177 aspirin. Mortality was lower among DOAC- vs VKA-users (aRR 0.82 [0.68-0.99]), but similar between clopidogrel vs aspirin users (aRR 1.04 [0.87-1.24]).

Conclusion

In this unselected cohort from a geographically defined Danish population, 90-day mortality after s-ICH was higher in patients with prior use of an OAC compared with no AT use or patients using a PA. Mortality was slightly lower for patients using a DOAC than a VKA. Mortality was also higher in PA- vs no AT-users, but there were no differences in mortality between clopidogrel vs aspirin.

Intracerebral haemorrhage - mechanisms, diagnosis and prospects for treatment and prevention

Intracerebral haemorrhage (ICH) is a devastating condition associated with high mortality and substantial residual disability among survivors. Effective treatments for the acute stages of ICH are limited. However, promising findings from randomized trials of therapeutic strategies, including acute care bundles that target anticoagulation therapies, blood pressure control and other physiological parameters, and trials of minimally invasive neurosurgical procedures have led to renewed optimism that patient outcomes can be improved. Currently ongoing areas of research for acute treatment include anti-inflammatory and haemostatic treatments. The implementation of effective secondary prevention strategies requires an understanding of the aetiology of ICH, which involves vascular and brain parenchymal imaging; the use of neuroimaging markers of cerebral small vessel disease improves classification with prognostic relevance. Other data underline the importance of preventing not only recurrent ICH but also ischaemic stroke and cardiovascular events in survivors of ICH. Ongoing and planned randomized controlled trials will assess the efficacy of prevention strategies, including antiplatelet agents, oral anticoagulants or left atrial appendage occlusion (in patients with concomitant atrial fibrillation), and optimal management of long-term blood pressure and statin use. Together, these advances herald a new era of improved understanding and effective interventions to reduce the burden of ICH.

Milvexian, a novel factor XIa inhibitor for stroke prevention: pharmacokinetic and pharmacodynamic evaluation

INTRODUCTION

Antiplatelets and oral anticoagulants are commonly used to treat patients with various cardiovascular and cerebrovascular diseases. However, the primary concern for clinicians remains the risk of bleeding, thus necessitating the development of new therapies. Milvexian is a new anticoagulant that inhibits factor XIa, preventing the pathological formation of thrombi without increasing bleeding risk.

AREAS COVERED

This drug evaluation examines the pharmacokinetic properties of milvexian and provides information on its pharmacodynamics and clinical efficacy in treating some cerebrovascular conditions.

EXPERT OPINION

Milvexian shows a good pharmacokinetic profile with low renal elimination rates, justifying its use in patients with a high degree of renal impairment, and without relevant drug-drug interactions. In patients affected by acute non-cardioembolic ischemic stroke or high-risk transient ischemic stroke, milvexian, in addition to dual antiplatelet therapy, seems to have a positive efficacy profile without any safety concerns, especially in terms of intracranial hemorrhage. Two phase 3 trials are ongoing to investigate the efficacy and safety of milvexian for preventing cardioembolic and non-cardioembolic ischemic stroke.

Andexanet alfa versus non-specific treatments for intracerebral hemorrhage in patients taking factor Xa inhibitors - Individual patient data analysis of ANNEXA-4 and TICH-NOAC

BACKGROUND

Data comparing the specific reversal agent andexanet alfa with non-specific treatments in patients with non-traumatic intracerebral hemorrhage (ICH) associated with factor-Xa inhibitor (FXaI) use are scarce.

AIM

The study aimed to determine the association between the use of andexanet alfa compared with non-specific treatments with the rate of hematoma expansion and thromboembolic complications in patients with FXaI-associated ICH.

METHODS

We performed an individual patient data analysis combining two independent, prospective studies: ANNEXA-4 (180 patients receiving andexanet alfa, NCT02329327) and TICH-NOAC (63 patients receiving tranexamic acid or placebo ± prothrombin complex concentrate, NCT02866838). The primary efficacy outcome was hematoma expansion on follow-up imaging. The primary safety outcome was any thromboembolic complication (ischemic stroke, myocardial infarction, pulmonary embolism, or deep vein thrombosis) at 30 days. We used binary logistic regression models adjusted for baseline hematoma volume, age, calibrated anti-Xa activity, times from last intake of FXaI, and symptom onset to treatment, respectively.

RESULTS

Among 243 participants included, the median age was 80 (IQR 75-84) years, baseline hematoma volume was 9.1 (IQR 3.4-21) mL and anti-Xa activity 118 (IQR 78-222) ng/mL. Times from last FXaI intake and symptom onset to treatment were 11 (IQR 7-16) and 4.7 (IQR 3.0-7.6) h, respectively. Overall, 50 patients (22%) experienced hematoma expansion (ANNEXA-4: n=24 (14%); TICH-NOAC: n=26 (41%)). After adjusting for pre-specified confounders (baseline hematoma volume, age, calibrated anti-Xa activity, times from last intake of FXaI, and symptom onset to treatment, respectively), treatment with andexanet alfa was independently associated with decreased odds for hematoma expansion (aOR 0.33, 95% CI 0.13-0.80, p = 0.015). Overall, 26 patients (11%) had any thromboembolic complication within 30 days (ANNEXA-4: n=20 (11%); TICH-NOAC: n=6 (10%)). There was no association between any thromboembolic complication and treatment with andexanet alfa (aOR 0.70, 95% CI 0.16-3.12, p = 0.641).

CONCLUSION

The use of andexanet alfa compared to any other non-specific treatment strategy was associated with decreased odds for hematoma expansion, without increased odds for thromboembolic complications.

Treatment for intracerebral hemorrhage: Dawn of a new era

Intracerebral hemorrhage (ICH) is a devastating disease, causing high rates of death, disability, and suffering across the world. For decades, its treatment has been shrouded by the lack of reliable evidence, and consequently, the presumption that an effective treatment is unlikely to be found. Neutral results arising from several major randomized controlled trials had established a negative spirit within and outside the stroke community. Frustration among researchers and a sense of nihilism in clinicians has created the general perception that patients presenting with ICH have a poor prognosis irrespective of them receiving any form of active management. All this changed in 2023 with the positive results on the primary outcome in randomized controlled trials showing treatment benefits for a hyperacute care bundle approach (INTERACT3), early minimal invasive hematoma evacuation (ENRICH), and use of factor Xa-inhibitor anticoagulation reversal with andexanet alfa (ANNEXa-I). These advances have now been extended in 2024 by confirmation that intensive blood pressure lowering initiated within the first few hours of the onset of symptoms can substantially improve outcome in ICH (INTERACT4) and that decompressive hemicraniectomy is a viable treatment strategy in patients with large deep ICH (SWITCH). This evidence will spearhead a change in the perception of ICH, to revolutionize the care of these patients to ultimately improve their outcomes. We review these and other recent developments in the hyperacute management of ICH. We summarize the results of randomized controlled trials and discuss related original research papers published in this issue of the International Journal of Stroke. These exciting advances demonstrate how we are now at the dawn of a new, exciting, and brighter era of ICH management.