Long-term outcomes of patients with embolic stroke of undetermined source according to subtype

The prognosis of patients with embolic stroke of undetermined source (ESUS) may vary according to the underlying cause. Therefore, we aimed to divide ESUS into subtypes and assess the long-term outcomes. Consecutive patients with acute ischemic stroke who underwent a comprehensive workup, including transesophageal echocardiography and prolonged electrocardiography monitoring, were enrolled. We classified ESUS into minor cardioembolic (CE) ESUS, arteriogenic ESUS, two or more causes ESUS, and no cause ESUS. Arteriogenic ESUS was sub-classified into complex aortic plaque (CAP) ESUS and non-stenotic (< 50%) relevant artery plaque (NAP) ESUS. A total of 775 patients were enrolled. During 1286 ± 748 days follow-up, 116 major adverse cardiovascular events (MACE) occurred (4.2 events/100 patient-years). Among the ESUS subtypes, CAP ESUS was associated with the highest MACE frequency (9.7/100 patient-years, p = 0.021). Cox regression analyses showed that CAP ESUS was associated with MACE (hazard ratio 2.466, 95% confidence interval 1.305-4.660) and any stroke recurrence (hazard ratio 2.470, 95% confidence interval, 1.108-5.508). The prognosis of ESUS varies according to the subtype, with CAP ESUS having the worst prognosis. Categorizing ESUS into subtypes could improve patient care and refine clinical trials.

Imaging Biomarkers and Prevalence of Complex Aortic Plaque in Cryptogenic Stroke: A Systematic Review

BACKGROUND

Complex aortic plaque (CAP) is a potential embolic source in patients with cryptogenic stroke (CS). We review CAP imaging criteria for transesophageal echocardiogram (TEE), computed tomography angiography (CTA), and magnetic resonance imaging and calculate CAP prevalence in patients with acute CS.

METHODS AND RESULTS

PubMed and EMBASE databases were searched up to December 2022 in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline. Two independent reviewers extracted data on study design, imaging techniques, CAP criteria, and prevalence. The Cochrane Collaboration tool and Guideline for Reporting Reliability and Agreement Studies were used to assess risk of bias and reporting completeness, respectively. From 2293 studies, 45 were reviewed for CAP imaging biomarker criteria in patients with acute CS (N=37 TEE; N=9 CTA; N=6 magnetic resonance imaging). Most studies (74%) used ≥4 mm plaque thickness as the imaging criterion for CAP although ≥1 mm (N=1, CTA), ≥5 mm (N=5, TEE), and ≥6 mm (N=2, CTA) were also reported. Additional features included mobility, ulceration, thrombus, protrusions, and assessment of plaque composition. From 23 prospective studies, CAP was detected in 960 of 2778 patients with CS (0.32 [95% CI, 0.24-0.41], I2=94%). By modality, prevalence estimates were 0.29 (95% CI, 0.20-0.40; I2=95%) for TEE; 0.23 (95% CI, 0.15-0.34; I2=87%) for CTA and 0.22 (95% CI, 0.06-0.54; I2=92%) for magnetic resonance imaging.

CONCLUSIONS

TEE was commonly used to assess CAP in patients with CS. The most common CAP imaging biomarker was ≥4 mm plaque thickness. CAP was observed in one-third of patients with acute CS. However, high study heterogeneity suggests a need for reproducible imaging methods.

Increased Mobility of the Atrial Septum in Aortic Root Dilation: An Observational Study on Transesophageal Echocardiography

Background: There is a growing interest in the relationship between atrial septal anatomy and cardioembolic stroke. Anecdotal reports suggest that the enlargement of the aortic root could interfere with atrial septal mobility (ASM). We sought to investigate the association between ASM and aortic root dilation.

Methods and Findings: From all consecutive clinically requested transesophageal echocardiogram (TEE) studies performed during the study period in a single institution, we were able to review and evaluate the ASM and anteroposterior length, aortic root diameter, and the prevalence of atrial septal aneurysm (ASA) and of patent foramen ovale (PFO) in 336 studies. Additional variables, such as left ventricular ejection fraction, left atrial diameter, diastolic dysfunction, age, sex, weight, height, previous stroke, atrial fibrillation, and TEE indication, were extracted from patient medical records and echocardiographic clinical reports. In 336 patients, we found a mean ASM of 3.4 mm, ranging from 0 to 21 mm; 15% had ASA and 14% had PFO. There was a 1.0 mm increase in ASM for every 10-mm increase in aortic root diameter adjusted for age, sex, weight, height, ejection fraction, and left atrial size (B = 0.1; P = 0.04). Aortic diameter was not associated with a smaller septal length (B = 0.03; P = 0.7).

Conclusion: An increased motion of the atrial septum can occur in association with aortic dilation. These findings deserve attention for the relevance of aortic root anatomy in future studies involving atrial septal characteristics and embolic stroke risk.

Serum bilirubin and ischaemic stroke: a review of literature

Bilirubin, a product of heme metabolism, is the most potent endogenous antioxidant which increases in many oxidative stress conditions such as stroke. It has been widely known to exert neuroprotective effect on stroke through mechanisms involved in development, therefore, it can influence the occurrence and prognosis of ischaemic stroke (IS). In this review, studies were identified by a comprehensive search of Pubmed, Embase, the Cochrane Library (Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Methodology Register) and Web of Science to examine the correlation between serum bilirubin levels and risks of developing IS as well as IS outcomes. Additional studies were identified by reviewing references and contacting authors.

Underlying embolic and pathologic differentiation by cerebral microbleeds in cryptogenic stroke

BACKGROUND

Cryptogenic stroke encompasses diverse emboligenic mechanisms and pathogeneses. Cerebral microbleeds (CMBs) occur differently among stroke subtypes. The association of CMBs with cryptogenic stroke is essentially unknown.

METHODS

CHALLENGE ESUS/CS (Mechanisms of Embolic Stroke Clarified by Transesophageal Echocardiography for ESUS/CS) is a multicenter registry with comprehensive data including gradient-echo T2*-weighted magnetic resonance imaging of cryptogenic stroke patients who underwent transesophageal echocardiography. Patients' clinical characteristics were compared according to the presence and location of CMBs.

RESULTS

A total of 661 patients (68.7 ± 12.7 years; 445 males) were enrolled, and 209 (32%) had CMBs. Age (odds ratio [OR] 1.02, 95% confidence interval [CI] 1.00-1.04, p = 0.020), male sex (OR 1.85, 95% CI 1.18-2.91, p = 0.007), hypertension (OR 1.71, 95% CI 1.03-2.86, p = 0.039), chronic kidney disease (OR 1.64, 95% CI 1.11-2.43, p = 0.013), deep and subcortical white matter hyperintensity (OR 1.82, 95% CI 1.16-2.85, p = 0.009), and periventricular hyperintensity (OR 2.18, 95% CI 1.37-3.46, p = 0.001) were independently associated with the presence of CMBs. Aortic complicated lesions (OR 1.78, 95% CI 1.12-2.84, p = 0.015) were associated with deep and diffuse CMBs, whereas prior anticoagulant therapy (OR 7.88, 95% CI, 1.83-33.9, p = 0.006) was related to lobar CMBs.

CONCLUSIONS

CMBs were common, and age, male sex, hypertension, chronic kidney disease, and cerebral white matter diseases were related to CMBs in cryptogenic stroke. Aortic complicated lesions were associated with deep and diffuse CMBs, while prior anticoagulant therapy was related to lobar CMBs.

Liver Function Indicators Performed Better to Eliminate Cardioembolic Stroke than to Identify It from Stroke Subtypes

BACKGROUND

Identifying the etiology of ischemic stroke is essential to acute management and secondary prevention. The value of liver function indicators in differentiating stroke subtypes remains to be evaluated.

METHODS

A total of 1333 acute ischemic stroke patients were included. Liver function indicators collected within 24 hours from stroke onset, including alanine aminotransferase, aspartate aminotransferase (AST), alkaline phosphatase, gamma-glutamyl transpeptidase (GGT), and bilirubin (BILI), were collapsed into quartiles (Q) and also dichotomized by Q1. Multivariate regression analysis was conducted to identify the independent association between liver function indicators and cardioembolic stroke (SCE). Area under the curve (AUC) of receiver operating characteristic analysis was conducted, and sensitivity (Sen), specificity (Spe), positive prospective value (PPV), and negative prospective value (NPV) were determined to evaluate the predictive value of liver function indicators for SCE.

RESULTS

AST, GGT, and BILI were associated with SCE. After adjustment, only AST was related to SCE independently. The incidence of SCE in the Q1 of AST, GGT, and BILI, particularly in the Q1 of AST, was quite low. The ability of AST, GGT, and BILI to identify SCE was poor, with low AUC, Sen, and PPV. The value of AST, GGT, and BILI in eliminating SCE from stroke subtypes was good, with high Spe and moderate NPV, and was enhanced after combining each liver function indicator.

CONCLUSIONS

Results of present study demonstrated that AST, GGT, and BILI, particularly AST, had a potential to eliminate SCE from stroke subtypes, and the ability of eliminating SCE would be strengthened after combining each liver function indicator together.

Association between Aortic Atheroma and Cerebral Small Vessel Disease in Patients with Ischemic Stroke

BACKGROUND AND PURPOSE

Cerebral small vessel disease (SVDs) are related with large artery atherosclerosis. However, the association between aortic atheroma (AA) and cerebral small vessel disease has rarely been reported. This study evaluated the relationship between presence and burden of AAs and those of SVDs in patients with acute ischemic stroke.

METHODS

We included 737 consecutive patients who underwent transesophageal echocardiography (TEE) and brain magnetic resonance imaging (MRI) for evaluation of acute stroke. AA subtypes were classified as complex aortic plaque (CAP) and simple aortic plaque (SAP). Presence and burden of SVDs including cerebral microbleeds (CMBs), white matter hyperintensities (WMHs), perivascular spaces (PVSs), asymptomatic lacunar infarctions (ALIs), and total SVD score, were investigated.

RESULTS

AA was found by TEE in 360 (48.8%) patients including 11.6% with CAP and 37.2% with SAP. One or more types of SVDs was found in 269 (36.4%) patients. In multivariable analysis, presence of CMBs (odds ratio [OR] 4.68), high-grade WMHs (OR 3.13), high-grade PVSs (OR 3.35), and ALIs (OR 4.24) were frequent in patients with AA than those without AA. Each 1-point increase in total SVD score increased the odds of presence of CAP (OR 1.94, 95% confidence interval (CI) 1.44-1.85) and SAP (OR 1.54, 95% CI 1.35-1.75).

CONCLUSIONS

In this study, patients with AA frequently had cerebral SVDs. Larger burden of AA was associated with advanced cerebral SVDs. Our findings give an additional information for positive relationship with systemic atherosclerosis and coexisting cerebral SVDs in acute ischemic stroke patients.

Age dependency of ischaemic stroke subtypes and vascular risk factors in western Norway: the Bergen Norwegian Stroke Cooperation Study

OBJECTIVES

Age dependency of acute ischaemic stroke aetiology and vascular risk factors have not been adequately evaluated in stroke patients in Norway. Aims of this study were to evaluate how stroke subtypes and vascular risk factors vary with age in a western Norway stroke population.

MATERIALS AND METHODS

Patients aged 15-100 years consecutively admitted to our neurovascular centre with acute ischaemic stroke between 2006 and 2012 were included. The study population was categorized as young (15-49 years), middle-aged (50-74 years) or elderly (≥ 75 years). Stroke aetiology was defined by TOAST criteria. Risk factors and history of cardiovascular disease were recorded.

RESULTS

In total, 2484 patients with acute cerebral infarction were included: 1418 were males (57.3%). Mean age was 70.8 years (SD ± 14.9), 228 patients were young, 1126 middle-aged, and 1130 were elderly. The proportion of large-artery atherosclerosis and of small-vessel occlusion was highest among middle-aged patients. The proportion of cardioembolism was high at all ages, especially among the elderly. The proportion of stroke of other determined cause was highest among young patients. Some risk factors (diabetes mellitus, active smoking, angina pectoris, prior stroke and peripheral artery disease) decreased among the elderly. The proportions of several potential causes increased with age.

CONCLUSION

The proportion of stroke subtypes and vascular risk factors are age dependent. Age 50-74 years constitutes the period in life where cardiovascular risk factors become manifest and stroke subtypes change.

Atherosclerosis in intracranial, extracranial, and coronary arteries with aortic plaques in patients with ischemic stroke of undetermined etiology

OBJECTIVE

We investigated the association of cerebral and coronary artery atherosclerosis with the presence, burden and type of atherosclerotic plaques of the aorta (AP) in patients with ischemic stroke of undetermined etiology.

METHODS

48 consecutive patients (32 males, mean age 68 ± 11 years) with acute ischemic stroke of unknown etiology after thorough stroke workup were investigated using ECG-gated CT-Angiography (CTA) for the detection of embolic AP. Intima media thickness (IMT), presence of carotid plaques and stenosis ≥ 50% and intracranial stenosis were assessed as parameters of cerebral atherosclerosis, the Agatston score (AS) and coronary artery stenosis ≥ 50% (CAS) in CTA as parameters of coronary atherosclerosis. Plaque burden was classified as mild or severe and plaque types were classified according to their morphology in calcified, non-calcified or mixed.

RESULTS

APs were found in 36 patients (75%). AP presence was associated with higher IMT values (p = 0.029), intracranial stenosis (p = 0.047), CAS (p = 0.033) and AS (p = 0.026). Twenty-three of 31 (74.2%) patients with both carotid atherosclerosis and AP revealed plaque calcification (p = 0.041). Ten of 14 (71.4%) patients with AP and intracranial stenosis had calcified plaques (p = 0.030). AP in more than one aortic segment was found in patients with bilateral carotid stenosis ≥ 50% (p = 0.038), intracranial stenosis (p = 0.042), high IMT (p = 0.040) and higher AS (p = 0.019).

CONCLUSIONS

Aortic atherosclerotic plaques are common in patients with ischemic stroke of undetermined etiology and in particular those with carotid, intracranial and coronary atherosclerosis or high IMT values. In these patients, CTA of aorta should be seriously considered.

Correlation between aortic/carotid atherosclerotic plaques and cerebral infarction

The aim of this study was to investigate the correlation between aortic/carotid atherosclerotic plaques and cerebral infarction. We examined 116 cases of cerebral infarction using transcranial Doppler ultrasound in order to exclude cerebrovascular stenosis. Transesophageal echocardiography and color Doppler ultrasound were used to detect aortic atherosclerotic plaques (AAPs) and carotid atherosclerotic plaques (CAPs). AAPs were detected in a total of 70 of the 116 cases (60.3%), including 56 with moderate/severe atherosclerotic changes (48.3%). The difference in the incidence of various types of infarction between APP severity levels was significant (P<0.01). Of the 116 cases, 64 had CAPs (55.2%), including 46 with unstable plaque (39.7%). The difference in the incidence of various types of infarction between CAP stability levels was significant (P<0.01). The results indicate that moderate/severe AAP and unstable CAP are significant causes of embolic infarction without stenosis in the internal carotid arteries.