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

Apolipoprotein E deficiency exacerbates blood-brain barrier disruption and hyperglycemia-associated hemorrhagic transformation after ischemic stroke

BACKGROUND

The polymorphism of the apolipoprotein E (ApoE) gene has been implicated in both the susceptibility to neurodegenerative disease and the prognosis of traumatic brain injury (TBI). However, the influence of ApoE on the risk of hemorrhagic transformation (HT) after acute ischemic stroke remains inconclusive. The present study aimed to investigate the potential impact of ApoE deficiency on the risk of hyperglycemia-associated HT and to elucidate the underlying mechanisms.

METHODS

Wild-type (WT) and ApoE knockout (ApoE-/-) mice were injected with 50 % glucose to induce hyperglycemia and subsequently subjected to 90 min of intraluminal middle cerebral artery occlusion (MCAO). The mortality, neurological function, HT incidence and HT grading-score were evaluated at 24 hours after reperfusion. To evaluate the integrity of blood-brain barrier (BBB), the immunoglobulin G (IgG) leakage and the protein expressions of tight junctions (TJs) were detected using immunofluorescent staining and western blotting. Finally, the levels of matrix metalloproteinases (MMP)-2/9, microglial activation and proinflammatory mediators were investigated using immunofluorescent staining and western blotting.

RESULTS

ApoE-/- mice exhibited increased mortality and exacerbated neurological impairment, concomitant with more severe hyperglycemia-associated HT 24 hours post-reperfusion. Meanwhile, ApoE deficiency exacerbated the disruption of BBB, characterized by increased leakage of IgG, aggravated degradation of TJs and microvascular basement membranes. Furthermore, ApoE deficiency further aggravated the upregulation of MMP-2/9 and microglia-triggered neuroinflammation.

CONCLUSIONS

Our findings demonstrate that the absence of ApoE exacerbates neurological impairment and hyperglycemia-associated HT in ischemic stroke mice, which is closely associated with MMP-2/9 signaling and neuroinflammation-mediated disruption of BBB.

Early vs late anticoagulation in acute ischemic stroke with indications outside atrial fibrillation

BACKGROUND

Current literature lacks guidance on the safety of administering anticoagulation in acute ischemic stroke with emergent indications that require anticoagulation other than atrial fibrillation. Therefore, we tend to rely on studies investigating acute ischemic stroke in atrial fibrillation for anticoagulation recommendations.

METHODS

We retrospectively reviewed data for patients with acute ischemic stroke who had a non-atrial fibrillation emergent indication for anticoagulation (e.g., intra-arterial thrombus, intracardiac thrombus, acute coronary syndrome, acute limb ischemia, deep vein thrombosis and pulmonary embolism) diagnosed within 3 days of acute ischemic stroke. Patients who received anticoagulation ≤ 3 days of stroke onset (Group A) were compared to those who either received it afterwards or did not receive it at all (Group B).

RESULTS

Out of the 558 patients, only 88 patients met our inclusion criteria. Of the total cohort, 55.7 % patients were males, and basic demographics were similar in both groups except for milder strokes in Group A (national institute of health stroke scale 6 vs. 12.5, p = 0.03). Only 2 patients in Group A and 1 patient in Group B developed intracranial hemorrhage, which was not statistically significant. Group A patients had a lower incidence of both new diagnosis (2 % vs. 34.2 % %, p < 0.001) and propagation of an established venous thromboembolism. They also had a lower rate of any thromboembolic complication (2 % vs. 42 %, p < 0.001).

CONCLUSION

Early anticoagulation (i.e., ≤ 3 days) in non-atrial fibrillation ischemic stroke patients with an emergent indication may be safe and carry a lower risk of thromboembolic complications than later anticoagulation.

Clinical value of a tool for managing oral anticoagulation in nonvalvular atrial fibrillation in primary health care. Randomized clinical trial

INTRODUCTION AND OBJECTIVES

The management of atrial fibrillation is complex and requires improvement at strategic points, such as in the control of patients treated with vitamin K antagonists. The aim of this study was to evaluate the impact on health outcomes of a nonvalvular atrial fibrillation decision support tool based on visualization of the time in therapeutic range in primary care.

METHODS

The present randomized clinical trial was conducted in 2018 with a 1-year follow-up in 325 primary care centers in Catalonia. In the intervention centers, the decision support tool was installed to control the time in therapeutic range of patients treated with vitamin K antagonists. The tool was not visualized in the control group.

RESULTS

In total, 44 556 patients were studied. The intervention protected against admission for stroke (adjusted odds ratio [OR], 0.70; 95% confidence interval [95%CI], 0.55-0.88). The number needed to treat was 3502 (95%CI, 3305-3725) while the number of admissions for stroke avoided was 12.63 (95%CI, 11.88-13.38). The intervention also protected against mortality (adjusted OR, 0.78; 95%CI, 0.67-0.90), with a number needed to treat of 13 687 (95%CI, 10 789-18 714) and number of deaths avoided of 3.23 (95%CI, 2.36-4.10).

CONCLUSIONS

The decision support tool was associated with slight reductions in the numbers of admissions for ischemic stroke and mortality. Although the follow-up time was short and the effect of the intervention was small, the results are valuable and could improve implementation of the tool. This clinical trial was registered with ClinicalTrials.gov (NCT03367325).

Key CT markers for predicting haemorrhagic transformation after ischaemic stroke: a prospective cohort study in China

OBJECTIVES

Limited studies have systematically addressed the CT markers of predicting haemorrhagic transformation (HT). We aimed to (1) investigate the predictive ability of the imaging factors on multimodal CT for HT and (2) identify the key CT markers that can accurately predict HT while maintaining easy and rapid assessment in the early stage of stroke.

DESIGN AND SETTING

This was a prospective cohort study conducted in a tertiary hospital in Southwest China.

PARTICIPANTS

Patients with ischaemic stroke admitted within 24 hours after onset were included.

OUTCOME MEASURES

The primary outcome was measured as the overall HT. The secondary outcomes were the presence of parenchymal haematoma, symptomatic HT and spontaneous HT.

RESULTS

A total of 763 patients were included. The early hypodensity >1/3 of the middle cerebral artery (MCA) territory, Alberta Stroke Programme Early CT Score≤7, midline shift, hyperdense middle cerebral artery sign (HMCAS), poor collateral circulation, infarct core and penumbra was independently associated with the increased risk of HT (all p < 0.05). The sensitivity of midline shift for predicting HT was only 3.5%, whereas its specificity was 99.8%. The combination of the early hypodensity >1/3 of the MCA territory, midline shift and HMCAS showed a good predictive performance for HT (area under the curve 0.80, 95% CI 0.75 to 0.84).

CONCLUSIONS

Seven imaging factors on multimodal CT were independently associated with HT. The high specificity of midline shift suggests the need to consider it as an imaging indicator when assessing the risk of HT. The early hypodensity >1/3 of the MCA territory, midline shift and HMCAS was identified as the key CT markers for the early prediction of HT. The coexistence of the three key factors might be a valuable index for identifying individuals at high bleeding risk and guiding further treatments.

Diagnostic Work-Up in Patients with Nonbacterial Thrombotic Endocarditis

Nonbacterial thrombotic endocarditis (NBTE) is a form of endocarditis that occurs in patients with predisposing conditions, including malignancies, autoimmune diseases (particularly antiphospholipid antibody syndrome, which accounts for the majority of lupus-associated cases), and coagulation disturbances for which the correlation with classical determinants is unclear. The condition is commonly referred to as "marantic", "verrucous", or Libman-Sacks endocarditis, although these are not synonymous, representing clinical-pathological nuances. The clinical presentation of NBTE involves embolic events, while local valvular complications, generally regurgitation, are typically less frequent and milder compared to infective forms of endocarditis. In the past, the diagnosis of NBTE relied on post mortem examinations, while at present, the diagnosis is primarily based on echocardiography, with the priority of excluding infective endocarditis through comprehensive microbiological and serological tests. As in other forms of endocarditis, besides pathology, transesophageal echocardiography remains the diagnostic standard, while other imaging techniques hold promise as adjunctive tools for early diagnosis and differentiation from infective vegetations. These include cardiac MRI and 18FDG-PET/CT, which already represents a major diagnostic criterion of infective endocarditis in specific settings. We will herein provide a comprehensive review of the current knowledge on the clinics and therapeutics of NBTE, with a specific focus on the diagnostic tools.

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.

Coming soon to a pharmacy near you? FXI and FXII inhibitors to prevent or treat thromboembolism

Anticoagulants have been in use for nearly a century for the treatment and prevention of venous and arterial thromboembolic disorders. The most dreaded complication of anticoagulant treatment is the occurrence of bleeding, which may be serious and even life-threatening. All available anticoagulants, which target either multiple coagulation factors or individual components of the tissue factor (TF) factor VIIa or the common pathways, have the potential to affect hemostasis and thus to increase bleeding risk in treated patients. While direct oral anticoagulants introduced an improvement in care for eligible patients in terms of safety, efficacy, and convenience of treatment, there remain unmet clinical needs for patients requiring anticoagulant drugs. Anticoagulant therapy is sometimes avoided for fear of hemorrhagic complications, and other patients are undertreated due to comorbidities and the perception of increased bleeding risk. Evidence suggests that the contact pathway of coagulation has a limited role in initiating physiologic in vivo coagulation and that it contributes to thrombosis more than it does to hemostasis. Because inhibition of the contact pathway is less likely to promote bleeding, it is an attractive target for the development of anticoagulants with improved safety. Preclinical and early clinical data indicate that novel agents that selectively target factor XI or factor XII can reduce venous and arterial thrombosis without an increase in bleeding complications.

Successful use of therapeutic anticoagulation therapy in two patients with moderate stroke from the second day of onset: A case report and literature review

Introduction and importance

Hemorrhagic transformation of ischemic stroke is one of the most traumatic consequences of ischemic stroke. Therefore, deciding the optimal time for anticoagulant application and its effect on clinical outcome, recurrence and risk for hemorrhagic transformation are still in quarry. The European Heart Rhythm Association recommends the usage of anticoagulants after 3–4 days after a mild stroke, 6 days after moderate stroke and 12 days after a severe stroke.

Case presentation

In our case report, we present two patients who started full therapeutic anticoagulation of low molecular weight heparin from the first day after moderate ischemic stroke, warfarin was added later guided by INR and discharged on oral anticoagulants for associated AF. They improved clinically with improved motor function for both upper and lower limbs, sensation and gaze without any complication followed by serial CT.

Clinical discussion and conclusion

As a result of this case report, clinical improvement has not been associated with hemorrhagic sequelae of anticoagulant administration on the first day. At this point, we recommend conducting a trial to study the effect of early application of anticoagulants from the first day on clinical outcome, recurrence, and hemorrhagic transfusion of stroke.

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The hemorrhagic transformation of ischemic stroke is one of the most traumatic outcomes.

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Therefore, determining the optimal time to apply anticoagulants.

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And their impact on clinical outcome, recurrence, and hemorrhagic transformation remains challenging.

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According to this case report, there are no hemorrhagic sequelae associated with the first day of anticoagulant therapy.

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Anticoagulation recommendations should therefore be supported or rejected based on more research.

Simultaneous cardio-cerebral infarction: a meta-analysis

BACKGROUND/INTRODUCTION

Cardio-cerebral infarction (CCI), which involves the simultaneous occurrence of acute ischaemic stroke and acute myocardial infarction, has a reported incidence of 0.0009%. Treatment of CCI presents a dilemma to physicians as both conditions are time critical. Despite the need for standardized treatment protocols, published data are sparse.

AIM

We aimed to summarize the reported cardio-cerebral infarction cases in the literature.

DESIGN

Meta-analysis.

METHODS

Four databases, Pubmed, Embase, Scopus and Google Scholar were searched until 25 August 2020. A title and abstract sieve, full-text review and extraction of data were conducted independently by three authors.

RESULTS

A total of 44 cases of CCI were identified from 37 case reports and series; 15 patients (34.1%) were treated using percutaneous coronary intervention (PCI) with stent, 8 patients (18.2%) were treated with a PCI without stent, 10 patients (22.7%) were treated via a cerebral vessel thrombectomy and 8 patients (18.2%) were treated via a thrombectomy of a coronary vessel. For medications, 20 patients (45.5%) were treated with thrombolytics, 10 patients (22.7%) were treated with anticoagulants, 8 patients (18.2%) were treated with antiplatelets and 11 patients (25.0%) were treated with anticoagulants and antiplatelets. Of 44 patients, 10 patients died, and 9 of those were due to cardiac causes. Among the 44 patients, days to death was observed to be a median of 2.0 days (interquartile range (IQR): 1.5, 4.0). The modified Rankin Score was measured in nine patients, with a median score of 2.0 (IQR: 1.0, 2.5) being reported.

DISCUSSION/CONCLUSION

The condition of CCI has substantial morbidity and mortality, and further studies are needed to examine the optimal diagnostic and treatment strategies of these patients.

Timing surgery and hemorrhagic complications in endocarditis with concomitant cerebral complications

BACKGROUND

To date, limited studies have been conducted regarding the safe timing of valvular repair for infectious endocarditis (IE) in patients with radiographic findings consistent with embolic stroke or infectious intracranial aneurysm (IIA).

METHODS

A single-center, retrospective review of valvular surgeries for IE was performed (2011-2019). Outcomes for patients who underwent cranial image screening and those who did not were subsequently compared.

RESULTS

276 patients underwent valvular repair for IE; 186 (67.4%) were male. The mean age was 51.0 (17.4) years. Mean time from imaging to surgery was 7.5 days. 124 (44.9%) underwent baseline cranial imaging. Of these, 22 (17.7%) had findings concerning for ischemic stroke from embolic origin. 65 patients underwent baseline diagnostic cerebral angiography. 10 (15%) of these patients harbored an IIA. Four out of these 10 (40%) underwent intervention for an IIA. Two of the four who underwent intervention (50.0%) had ruptured IIAs. The remaining six (60%) patients with IIAs received treatment with antibiotics alone. None of the patients with IIAs suffered from symptomatic hemorrhage after valvular surgery. No significant difference in symptomatic hemorrhage after valvular surgery between those with ischemic embolic stroke compared to those without (ischemic stroke-4.5% vs. no ischemic stroke-1.0%; p = 0.32).

CONCLUSIONS

Patients with radiographic evidence of ischemic stroke from septic emboli can safely undergo valvular surgery for IE without increased risk of symptomatic hemorrhage. We advocate for baseline CTA screening to evaluate for IIA in patients who present with a primary diagnosis of IE and propose a management algorithm.

A Review of Risk Factors and Predictors for Hemorrhagic Transformation in Patients with Acute Ischemic Stroke

Acute ischemic strokes (AIS) and hemorrhagic strokes lead to disabling neuropsychiatric and cognitive deficits. A serious and fatal complication of AIS is the occurrence of hemorrhagic transformation (HT). HT is cerebral bleeding that occurs after an ischemic event in the infarcted areas. This review summarises how specific risk factors such as demographic factors like age, gender, and race/ethnicity, comorbidities including essential hypertension, atrial fibrillation, diabetes mellitus, congestive heart failure, and ischemic heart disease along with predictors like higher NIHSS score, larger infarction size, cardioembolic strokes, systolic blood pressure/pulse pressure variability, higher plasma glucose levels, and higher body temperature during ischemic event, lower low-density lipoprotein and total cholesterol, early ischemic changes on imaging modalities, and some rare causes make an individual more susceptible to developing HT. We also discuss few other risk factors such as the role of blood-brain barrier, increased arterial stiffness, and globulin levels in patients postreperfusion using thrombolysis and mechanical thrombectomy. In addition, we discuss the implications of dual antiplatelet therapy and the length of treatment in reference to the incidence of developing HT. Current research into inflammatory mediators and biomarkers such as Cyclooxygenase-2, matrix metalloproteinases, and soluble ST2 and their potential role as treatment options for HT is also briefly discussed. Finally, this review calls for more research into use of dual antiplatelet and the timing of antiplatelet and anticoagulant use in reference to hemorrhagic transformation.

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.

New Avenues for Optimal Treatment of Atrial Fibrillation and Stroke Prevention

One in 3 individuals free of atrial fibrillation (AF) at index age 55 years is estimated to develop AF later in life. AF increases not only the risk of ischemic stroke but also of dementia, even in stroke-free patients. In this review, we address recent advances in the heart-brain interaction with focus on AF. Issues discussed are (1) the timing of direct oral anticoagulants start following an ischemic stroke; (2) the comparison of direct oral anticoagulants versus vitamin K antagonists in early secondary stroke prevention; (3) harms of bridging with heparin before direct oral anticoagulants; (4) importance of appropriate direct oral anticoagulants dosing; (5) screening for AF in high-risk populations, including the role of wearables; (6) left atrial appendage occlusion as an alternative to oral anticoagulation; (7) the role of early rhythm-control therapy; (8) effect of lifestyle interventions on AF; (9) AF as a risk factor for dementia. An interdisciplinary approach seems appropriate to address the complex challenges posed by AF.

Stroke prevention strategies in high-risk patients with atrial fibrillation

Effective stroke prevention with oral anticoagulation (OAC) is the cornerstone of the management of patients with atrial fibrillation. The use of OAC reduces the risk of stroke and death. For most patients with atrial fibrillation without moderate or severe mitral valve stenosis or prosthetic mechanical heart valves, treatment options include vitamin K antagonists, such as warfarin, and non-vitamin K antagonist oral anticoagulants (NOACs). Although most guidelines generally recommend NOACs as the first-line OAC, caution is required in some groups of patients with atrial fibrillation at high risk of stroke and bleeding who have been under-represented or not studied in the randomized clinical trials on NOACs for stroke prevention. In addition to OAC, non-pharmacological, percutaneous therapies, including left atrial appendage occlusion, for stroke prevention have emerged, sometimes used in combination with catheter ablation for the treatment of the atrial fibrillation. High-risk groups of patients with atrial fibrillation include patients with end-stage renal failure (including those receiving dialysis), extremely old patients (such as those aged >80 years with multiple risk factors for bleeding), patients with dementia or those living in a long-term care home, patients with previous intracranial bleeding or recent acute bleeding (such as gastrointestinal bleeding), patients with acute ischaemic stroke and patients with an intracardiac thrombus. This Review provides an overview of stroke prevention strategies, including left atrial appendage occlusion, in patients with atrial fibrillation at high risk of stroke and bleeding.

Screening of Embolic Sources by Point-of-Care Ultrasound in the Acute Phase of Ischemic Stroke

Our objective was to evaluate hand-held echocardiography as point of care ultrasound scanning (POCUS) to detect sources of embolism in the acute phase of stroke. Prospective, unicentric observational cohort study of non-lacunar ischemic stroke patients evaluated by V Scan device. The main sources of embolism (MSEs) were classified into embolic valvulopathies and severe ventricular dysfunction. We looked for atrial fibrillation (AF) predictors in strokes of undetermined etiology. MSEs were detected in 19.23% (25/130). Large vessel occlusion (LVO) (odds ratio [OR]: 4.24, 95% confidence interval [CI]: 1.01-17.85) and chronic heart failure (OR: 13.25, 95% CI: 3.54-49.50) were independent predictors of MSEs. LVO (OR: 6.54, 95% CI: 1.62-26.27) and left atrial area >20 cm² (OR: 7.01, 95% CI: 1.75-28.09) independently predicted AF. Patients with LVO and chronic heart disease may benefit from hand-held echocardiography as part of POCUS in the acute phase of ischemic stroke. Left atrial area measured was an independent predictor of AF in strokes of undetermined etiology.