Cerebral amyloid angiopathy-related transient focal neurological episodes: A transient ischemic attack mimic with an increased risk of intracranial hemorrhage

Cingulate sulcus sign: a descriptive analysis in a cerebral small vessel disease population

Objective

The cingulate sulcus sign (CSS) has been observed in patients with idiopathic normal pressure hydrocephalus (iNPH), suggesting potential disruptions in cerebrospinal fluid circulation and compromised glymphatic system. Although there are similarities in the underlying mechanisms between cerebral small vessel disease (CSVD) and iNPH, the relationship between CSS and CSVD remains unclear. This study aimed to investigate the prevalence and potential mechanisms of CSS in patients with CSVD.

Methods

Data from patients diagnosed with CSVD at Shengjing Hospital of China Medical University between January 2020 and October 2022 were retrospectively collected, including general information, global cognitive function [assessed by measuring Mini-Mental State Examination (MMSE)], and four CSVD magnetic resonance imaging (MRI) markers [(white matter hyperintensity (WMH), cerebral microbleeds (CMBs), lacunes, and enlarged perivascular spaces (EPVS)], CSS and the Evan's index (EI).

Results

A total of 308 patients were included, and CSS was detected in 80 patients (26%). Univariate analysis revealed that MMSE scores in the CSS group were significantly lower compared to the non-CSS group (p < 0.001). Multivariable analysis showed an independent correlation between CSS and the presence of lacunes (odds ratio [OR] 0.358, 95% confidence interval [CI] 0.193-0.663, p = 0.001), presence of lobar dominant CMBs (OR 2.683, 95%CI 1.385-5.195, p = 0.003), periventricular WMH Fazekas score (OR 1.693, 95% CI 1.133-2.529, p = 0.01), and EI (OR 1.276, 95% CI 1.146-1.420, p < 0.001).

Conclusion

This preliminary study showed that CSS can be observed in some patients with CSVD. The presence of CSS may represent different mechanisms of CSVD pathogenesis and reflect differences in the degree of cerebrospinal fluid (CSF)/interstitial fluid (ISF) stasis.

Cerebral Amyloid Angiopathy: An Undeniable Small Vessel Disease

Cerebral amyloid angiopathy (CAA) has been proven to be the most common pathological change in cerebral small vessel disease except arteriosclerosis. In recent years, with the discovery of imaging technology and new imaging markers, the diagnostic rate of CAA has greatly improved. CAA plays an important role in non-hypertensive cerebral hemorrhage and cognitive decline. This review comprehensively describes the etiology, epidemiology, pathophysiological mechanisms, clinical features, imaging manifestations, imaging markers, diagnostic criteria, and treatment of CAA to facilitate its diagnosis and treatment and reduce mortality.

When Atrial Fibrillation Meets Cerebral Amyloid Angiopathy: Current Evidence and Strategies

Non-valvular atrial fibrillation (AF) and cerebral amyloid angiopathy (CAA) are two common diseases in elderly populations. Despite the effectiveness of oral anticoagulant therapy in cardioembolic stroke prevention, intracranial hemorrhage represents the most serious complication of these therapies. Cerebral amyloid angiopathy is one of the main risk factors for spontaneous intracranial bleeding, and this risk is highly increased by age and concomitant antithrombotic therapies. Cerebral amyloid angiopathy can be silent for years and then manifest with clinical features simulating TIA (TIA-mimics) or stroke in AF patients, pushing clinicians to rapidly start VKAs or DOACs, thus increasing the risk of intracranial bleeding if the diagnosis of CAA was unknown. Because the cerebral amyloid angiopathy is easily diagnosed with non-contrast MRI, suspecting the disease can avoid catastrophic complications. In this review, we will provide physicians managing anticoagulant therapies with key tips to familiarize themselves with cerebral amyloid angiopathy, with a focus on the possible clinical presentations and on the diagnostic criteria.

Incidence and risk factors associated with seizures in cerebral amyloid angiopathy

BACKGROUND AND PURPOSE

Cerebral amyloid angiopathy (CAA) is a common cause of intracranial hemorrhage (ICH), which is a risk factor for seizures. The incidence and risk factors of seizures associated with a heterogeneous cohort of CAA patients have not been studied.

METHODS

We conducted a retrospective study of patients with CAA treated at Mayo Clinic Florida between 1 January 2015 and 1 January 2021. CAA was defined using the modified Boston criteria version 2.0. We analyzed electrophysiological and clinical features, and comorbidities including lobar ICH, nontraumatic cortical/convexity subarachnoid hemorrhage (cSAH), superficial siderosis, and inflammation (CAA with inflammation [CAA-ri]). Cognition and mortality were secondary outcomes. Univariate and multivariate analyses were performed to determine risk of seizures relative to clinical presentation.

RESULTS

Two hundred eighty-four patients with CAA were identified, with median follow-up of 35.7 months (interquartile range = 13.5-61.3 months). Fifty-six patients (19.7%) had seizures; in 21 (37.5%) patients, seizures were the index feature leading to CAA diagnosis. Seizures were more frequent in females (p = 0.032) and patients with lobar ICH (p = 0.002), cSAH (p = 0.030), superficial siderosis (p < 0.001), and CAA-ri (p = 0.005), and less common in patients with microhemorrhage (p = 0.006). After controlling for age and sex, lobar ICH (odds ratio [OR] = 2.1, 95% confidence interval [CI] = 1.1-4.2), CAA-ri (OR = 3.8, 95% CI = 1.4-10.3), and superficial siderosis (OR = 3.7, 95% CI = 1.9-7.0) were independently associated with higher odds of incident seizures.

CONCLUSIONS

Seizures are common in patients with CAA and are independently associated with lobar ICH, CAA-ri, and superficial siderosis. Our results may be applied to optimize clinical monitoring and management for patients with CAA.

Decreased Cerebrospinal Fluid Amyloid β 38, 40, 42, and 43 Levels in Sporadic and Hereditary Cerebral Amyloid Angiopathy

OBJECTIVE

Vascular amyloid β (Aβ) accumulation is the hallmark of cerebral amyloid angiopathy (CAA). The composition of cerebrospinal fluid (CSF) of CAA patients may serve as a diagnostic biomarker of CAA. We studied the diagnostic potential of the peptides Aβ38, Aβ40, Aβ42, and Aβ43 in patients with sporadic CAA (sCAA), hereditary Dutch-type CAA (D-CAA), and Alzheimer disease (AD).

METHODS

Aβ peptides were quantified by immunoassays in a discovery group (26 patients with sCAA and 40 controls), a validation group (40 patients with sCAA, 40 patients with AD, and 37 controls), and a group of 22 patients with D-CAA and 54 controls. To determine the diagnostic accuracy, the area under the curve (AUC) was calculated using a receiver operating characteristic curve with 95% confidence interval (CI).

RESULTS

We found decreased levels of all Aβ peptides in sCAA patients and D-CAA patients compared to controls. The difference was most prominent for Aβ42 (AUC of sCAA vs controls for discovery: 0.90, 95% CI = 0.82-0.99; for validation: 0.94, 95% CI = 0.89-0.99) and Aβ43 (AUC of sCAA vs controls for discovery: 0.95, 95% CI = 0.88-1.00; for validation: 0.91, 95% CI = 0.83-1.0). All Aβ peptides except Aβ43 were also decreased in sCAA compared to AD (CSF Aβ38: AUC = 0.82, 95% CI = 0.71-0.93; CSF Aβ40: AUC = 0.88, 95% CI = 0.80-0.96; CSF Aβ42: AUC = 0.79, 95% CI = 0.66-0.92).

INTERPRETATION

A combined biomarker panel of CSF Aβ38, Aβ40, Aβ42, and Aβ43 has potential to differentiate sCAA from AD and controls, and D-CAA from controls. ANN NEUROL 2023;93:1173-1186.

Associations between computed tomography markers of cerebral small vessel disease and hemorrhagic transformation after intravenous thrombolysis in acute ischemic stroke patients

Background

Hemorrhagic transformation (HT) is common among acute ischemic stroke patients after treatment with intravenous thrombolysis (IVT). We analyzed potential relationships between markers of cerebral small vessel disease (CSVD) and HT in patients after IVT.

Methods

This study retrospectively analyzed computed tomography (CT) data for acute ischemic stroke patients before and after treatment with recombinant tissue plasminogen activator at a large Chinese hospital between July 2014 and June 2021. Total CSVD score were summed by individual CSVD markers including leukoaraiosis, brain atrophy and lacune. Binary regression analysis was used to explore whether CSVD markers were related to HT as the primary outcome or to symptomatic intracranial hemorrhage (sICH) as a secondary outcome.

Results

A total of 397 AIS patients treated with IVT were screened for inclusion in this study. Patients with missing laboratory data (n = 37) and patients treated with endovascular therapy (n = 42) were excluded. Of the 318 patients included, 54 (17.0%) developed HT within 24–36 h of IVT, and 14 (4.3%) developed sICH. HT risk was independently associated with severe brain atrophy (OR 3.14, 95%CI 1.43–6.92, P = 0.004) and severe leukoaraiosis (OR 2.41, 95%CI 1.05–5.50, P = 0.036), but not to severe lacune level (OR 0.58, 95%CI 0.23–1.45, P = 0.250). Patients with a total CSVD burden ≥1 were at higher risk of HT (OR 2.87, 95%CI 1.38–5.94, P = 0.005). However, occurrence of sICH was not predicted by CSVD markers or total CSVD burden.

Conclusion

In patients with acute ischemic stroke, severe leukoaraiosis, brain atrophy and total CSVD burden may be risk factors for HT after IVT. These findings may help improve efforts to mitigate or even prevent HT in vulnerable patients.

Etiology and Clinical Significance of Network Hyperexcitability in Alzheimer's Disease: Unanswered Questions and Next Steps

Cortical network hyperexcitability related to synaptic dysfunction in Alzheimer's disease (AD) is a potential target for therapeutic intervention. In recent years, there has been increased interest in the prevalence of silent seizures and interictal epileptiform discharges (IEDs, or seizure tendency), with both entities collectively termed "subclinical epileptiform activity" (SEA), on neurophysiologic studies in AD patients. SEA has been demonstrated to be common in AD, with prevalence estimates ranging between 22-54%. Converging lines of basic and clinical evidence imply that modifying a hyperexcitable state results in an improvement in cognition. In particular, though these results require further confirmation, post-hoc findings from a recent phase II clinical trial suggest a therapeutic effect with levetiracetam administration in patients with AD and IEDs. Here, we review key unanswered questions as well as potential clinical trial avenues. Specifically, we discuss postulated mechanisms and treatment of hyperexcitability in patients with AD, which are of interest in designing future disease-modifying therapies. Criteria to prompt screening and optimal screening methodology for hyperexcitability have yet to be defined, as does timing and personalization of therapeutic intervention.

Transient unilateral weakness: is it a transient ischaemic attack?

Transient ischaemic attack is an emergency medical condition that causes brief negative focal neurological symptoms such as unilateral weakness. The symptoms herald a high risk of stroke and hence require urgent assessment. The challenge lies in the brevity and compendium of associated symptoms that can ‘mimic’ a plethora of other conditions. The result is a high rate of referrals to transient ischaemic attack clinics for these stroke mimics. This article highlights the diagnostic challenges in transient ischaemic attack with relevance to unilateral weakness.

Cerebral Amyloid Angiopathy and Atrial Fibrillation: An up to Date Case Report

Concurrent Cerebral Amyloid Angiopathy (CAA) and Atrial Fibrillation are becoming an increasingly common dilemma in clinical practice due to the aging population and the comorbidities associated with it. In such patients, the physician must appreciate and strike the difficult balance between the risk of ischemic strokes from atrial fibrillation on one hand, and that of intracerebral hemorrhage from coexisting CAA on the other. Anticoagulation is necessary for the former but potentially deleterious for the latter. In this case report, we present the case of a 67-year-old woman with a long history of atrial fibrillation on rivaroxaban who recently began to experience recurrent transient neurological deficits that were later diagnosed as amyloid spells related to concomitant CAA. While there is no clear-cut consensus in published literature on how to best manage these patients regarding the use of anticoagulation, it is recommended to involve a multidisciplinary team for optimal management of these patients.

Transient Focal Neurological Events in Cerebral Amyloid Angiopathy and the Long-term Risk of Intracerebral Hemorrhage and Death: A Systematic Review and Meta-analysis

Importance

Transient focal neurological episodes (TFNEs) are a frequently overlooked presentation of cerebral amyloid angiopathy (CAA), a condition with prognostic implications that are still not well described.

Objective

To perform a systematic review and meta-analysis to examine the factors associated with incident lobar intracerebral hemorrhage (ICH) and death in patients with CAA presenting with TFNEs.

Data Sources

A systematic review and individual participant meta-analysis including (1) a hospital-based cohort and (2) the results obtained from a systematic search performed in MEDLINE and Embase completed in December 2019.

Study Selection

Included studies were observational reports of TFNEs. Patient-level clinical, imaging, and prognostic data were required for inclusion. For aggregate data studies, patient-level data were requested. Disagreements were resolved by consensus.

Data Extraction and Synthesis

Data were extracted following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines by 4 independent reviewers. The quality of reports was determined based on the modified Pearson Case Report Quality Scale.

Main Outcomes and Measures

The clinical characteristics of TFNEs, neuroimaging features, and use of antithrombotics during follow-up were considered exposures. The predefined main outcomes were lobar ICH and risk of death during follow-up.

Results

Forty-two studies and 222 CAA-associated TFNE cases were included from the initial 1612 records produced by the systematic search; 26 additional patients (11 men [42.3%]; mean [SD] age, 77 [8] years) were provided by the hospital-based cohort. A total of 108 TFNEs (43.5%) consisted of motor symptoms. Convexity subarachnoid hemorrhage and cortical superficial siderosis were detected in 193 individuals (77.8%) and 156 individuals (62.9%) in the systematic search and hospital-based cohort, respectively. Follow-up duration could be obtained in 185 patients (median duration, 1 year [IQR, 0.8-2.5 years]). During follow-up, symptomatic lobar ICH occurred in 76 patients (39.4%). Motor symptoms (odds ratio, 2.08 [95% CI, 1.16-3.70]) at baseline and antithrombotic use during follow-up (odds ratio, 3.61 [95% CI, 1.67-7.84]) were associated with an increase in risk of lobar ICH. A total of 31 patients (16.5%) died during follow-up; lobar ICH during follow-up and cortical superficial siderosis were the main risk factors for death (odds ratio, 3.01 [95% CI, 1.36-6.69]; odds ratio, 3.20 [95% CI, 1.16-8.91], respectively).

Conclusions and Relevance

Patients presenting with CAA-associated TFNEs are at high risk of lobar ICH and death. Motor TFNEs and use of antithrombotics after a TFNE, in many cases because of misdiagnosis, are risk factors for ICH, and therefore accurate diagnosis and distinguishing this condition from transient ischemic attacks is critical.

Protein Aggregation in the Pathogenesis of Ischemic Stroke

Despite the distinction between ischemic stroke and neurodegenerative disorders, they share numerous pathophysiologies particularly those mediated by inflammation and oxidative stress. Although protein aggregation is considered to be a hallmark of neurodegenerative diseases, the formation of protein aggregates can be also induced within a short time after cerebral ischemia, aggravating cerebral ischemic injury. Protein aggregation uncovers a previously unappreciated molecular overlap between neurodegenerative diseases and ischemic stroke. Unfortunately, compared with neurodegenerative disease, mechanism of protein aggregation after cerebral ischemia and how this can be averted remain unclear. This review highlights current understanding on protein aggregation and its intrinsic role in ischemic stroke.

Stopping "transient ischemic attacks" by antiplatelet withdrawal

Introduction

Transient ischemic attack (TIA) is considered to be an important risk factor for the development of ischemic stroke and requires complete etiopathogenic evaluation and prompt initiation of secondary prevention treatment. In addition, an accurate differential diagnosis should be performed in order to exclude other disorders mimicking TIA.

Methods

In this case report, we describe the clinical and neuroimaging evaluation and the differential diagnosis of a patient with suspected crescendo TIAs.

Results

A 79-year-old man presented with recurrent episodes of right-sided numbness over the past 7 months, despite different single and dual antiplatelet therapies that were sequentially prescribed for suspected TIAs. Brain MRI revealed cortical superficial siderosis, symmetrical periventricular leukoencephalopathy and enlarged perivascular spaces. Cerebral amyloid angiopathy was considered in the differential diagnosis of the patient. Antiplatelet withdrawal was recommended and led to complete remission of the patient’s transient focal neurological episodes (TFNE) that were initially misdiagnosed as TIAs.

Discussion

Cortical superficial siderosis has been implicated as a key neuroimaging feature of cerebral amyloid angiopathy, a diagnosis which can be supported by the additional radiological findings of symmetrical white matter hyperintensities and enlarged perivascular spaces. Antiplatelet treatment in patients with cortical superficial siderosis may increase the frequency and severity of TFNE, while it increases exponentially the risk of intracerebral hemorrhage. The present case highlights that recognition of cortical superficial siderosis is crucial in the management of patients presenting with transient focal neurological symptoms that can be misdiagnosed as recurrent TIAs.

Perfusion-weighted MRI in cerebral amyloid angiopathy-related transient focal neurological episodes

INTRODUCTION

Sporadic cerebral amyloid angiopathy (CAA) is a common age-related cerebral small vessel disease characterized by progressive ß-amyloid deposition in the walls of small cortical arteries, arterioles, and capillaries in the cerebral cortex and overlying leptomeninges. CAA-related transient focal neurological episodes (CAA-TFNEs) represent a challenging clinical feature interesting from a pathophysiological point of view.

CASE REPORT

Here we present two cases of CAA-TFNEs in which we performed functional imaging with perfusion-weighted imaging MR and brain 18 F-FDG PET. In both cases, we found a topographic relationship between the involved cortical areas and the clinical expression of CAA-TFNEs. Cortical superficial siderosis in the first case and a convexity subarachnoid hemorrhage in the second case were found in the contralateral rolandic area corresponding to the clinical symptoms. The same areas showed a reduction of rCBV and rCBF on perfusion-weighted MR and were also associated in one case with hypometabolism on 18 F-FDG PET.

DISCUSSION

These new findings strengthen the hypothesis that CAA involves the superficial leptomeningeal arteries but also the short penetrating arterioles reaching different depths in the cortex generating hypoperfusion and altered vascular reactivity and consequently reduced neuronal activity.

CONCLUSION

Understanding CAA-TFNEs is pivotal because they carry a very high risk of subsequent lobar intracerebral hemorrhage but are frequently misdiagnosed as TIAs and treated with antithrombotics enhancing the bleeding risk associated with CAA.

Hemorrhagic Transformation After Tissue Plasminogen Activator Treatment in Acute Ischemic Stroke

Hemorrhagic transformation (HT) is a common complication after thrombolysis with recombinant tissue-type plasminogen activator (rt-PA) in ischemic stroke. In this article, recent research progress of HT in vivo and in vitro studies was reviewed. We have discussed new potential mechanisms and possible experimental models of HT development, as well as possible biomarkers and treatment methods. Meanwhile, we compared and analyzed rodent models, large animal models and in vitro BBB models of HT, and the limitations of these models were discussed. The molecular mechanism of HT was investigated in terms of BBB disruption, rt-PA neurotoxicity and the effect of neuroinflammation, matrix metalloproteinases, reactive oxygen species. The clinical features to predict HT were represented including blood biomarkers and clinical factors. Recent progress in neuroprotective strategies to improve HT after stroke treated with rt-PA is outlined. Further efforts need to be made to reduce the risk of HT after rt-PA therapy and improve the clinical prognosis of patients with ischemic stroke.

The frequency of central nervous system complications in the Cypriot cohort of ATTRV30M neuropathy transplanted patients

BACKGROUND

Hereditary transthyretin amyloidosis (ATTR) is a hereditary, sensorimotor and autonomic neuropathy caused by deposits of mutated transthyretin (TTR). The commonest TTR mutation is V30M (ATTRV30M) with patients usually living for about 10 years after disease onset. Liver transplantation (LT) until recently was considered the standard treatment.

OBJECTIVE AND METHODS

This study aims to assess the frequency of CNS complications in post-LT patients from the Cypriot cohort. Epidemiological data were collected for all genetically confirmed ATTRV30M neuropathy patients diagnosed at CING since 1992, and CNS-associated symptoms were assessed and evaluated by two neurology specialists.

RESULTS

Out of the 48 transplanted patients, 10 (20.8%) presented with a CNS complication. All patients had ocular involvement, mainly glaucoma (7/10). Eight presented with transient focal neurological episodes (TFNEs), with expressive dysphasia being reported by four of them. The mean time of TFNE-emergence was 16.6 years after the LT. Three died from cerebral hemorrhage.

CONCLUSIONS

CNS complications in post-LT ATTRV30M patients are not rare and usually manifest themselves at a time that surpasses the mean time the patients would have survived without a LT. CNS involvement is associated with increased mortality, due to cerebral hemorrhage.