Cardiac workup of ischemic stroke: can we improve our diagnostic yield?

Early Cardiac Evaluation, Abnormal Test Results, and Associations with Outcomes in Patients with Acute Brain Injury Admitted to a Neurocritical Care Unit

Background: to examine factors associated with cardiac evaluation and associations between cardiac test abnormalities and clinical outcomes in patients with acute brain injury (ABI) due to acute ischemic stroke (AIS), spontaneous subarachnoid hemorrhage (SAH), spontaneous intracerebral hemorrhage (sICH), and traumatic brain injury (TBI) requiring neurocritical care. Methods: In a cohort of patients ≥18 years, we examined the utilization of electrocardiography (ECG), beta-natriuretic peptide (BNP), cardiac troponin (cTnI), and transthoracic echocardiography (TTE). We investigated the association between cTnI, BNP, sex-adjusted prolonged QTc interval, low ejection fraction (EF < 40%), all-cause mortality, death by neurologic criteria (DNC), transition to comfort measures only (CMO), and hospital discharge to home using univariable and multivariable analysis (adjusted for age, sex, race/ethnicity, insurance carrier, pre-admission cardiac disorder, ABI type, admission Glasgow Coma Scale Score, mechanical ventilation, and intracranial pressure [ICP] monitoring). Results: The final sample comprised 11,822 patients: AIS (46.7%), sICH (18.5%), SAH (14.8%), and TBI (20.0%). A total of 63% (n = 7472) received cardiac workup, which increased over nine years (p < 0.001). A cardiac investigation was associated with increased age, male sex (aOR 1.16 [1.07, 1.27]), non-white ethnicity (aOR), non-commercial insurance (aOR 1.21 [1.09, 1.33]), pre-admission cardiac disorder (aOR 1.21 [1.09, 1.34]), mechanical ventilation (aOR1.78 [1.57, 2.02]) and ICP monitoring (aOR1.68 [1.49, 1.89]). Compared to AIS, sICH (aOR 0.25 [0.22, 0.29]), SAH (aOR 0.36 [0.30, 0.43]), and TBI (aOR 0.19 [0.17, 0.24]) patients were less likely to receive cardiac investigation. Patients with troponin 25th-50th quartile (aOR 1.65 [1.10-2.47]), troponin 50th-75th quartile (aOR 1.79 [1.22-2.63]), troponin >75th quartile (aOR 2.18 [1.49-3.17]), BNP 50th-75th quartile (aOR 2.86 [1.28-6.40]), BNP >75th quartile (aOR 4.54 [2.09-9.85]), prolonged QTc (aOR 3.41 [2.28; 5.30]), and EF < 40% (aOR 2.47 [1.07; 5.14]) were more likely to be DNC. Patients with troponin 50th-75th quartile (aOR 1.77 [1.14-2.73]), troponin >75th quartile (aOR 1.81 [1.18-2.78]), and prolonged QTc (aOR 1.71 [1.39; 2.12]) were more likely to be associated with a transition to CMO. Patients with prolonged QTc (aOR 0.66 [0.58; 0.76]) were less likely to be discharged home. Conclusions: This large, single-center study demonstrates low rates of cardiac evaluations in TBI, SAH, and sICH compared to AIS. However, there are strong associations between electrocardiography, biomarkers of cardiac injury and heart failure, and echocardiography findings on clinical outcomes in patients with ABI. Findings need validation in a multicenter cohort.

Gender Predicts Differences in Acute Ischemic Cardioembolic Stroke Profile: Emphasis on Woman-Specific Clinical Data and Early Outcome-The Experience of Sagrat Cor Hospital of Barcelona Stroke Registry

Background and Objectives: Acute ischemic cardioembolic stroke (CS) is a clinical condition with a high risk of death, and can lead to dependence, recurrence, and dementia. Materials and Methods: In this study, we evaluated gender differences and female-specific clinical data and early outcomes in 602 women diagnosed with CS from a total of 4600 consecutive acute stroke patients in a single-center hospital stroke registry over 24 years. A comparative analysis was performed in women and men in terms of demographics, cerebrovascular risk factors, clinical data, and early outcomes. Results: In a multivariate analysis, age, hypertension, valvular heart disease, obesity, and internal capsule location were independent variables associated with CS in women. The overall in-hospital mortality rate was similar, but the group of women had a greater presence of neurological deficits and a higher percentage of severe limitation at hospital discharge. After the multivariate analysis, age, altered consciousness, limb weakness, and neurological, respiratory, gastrointestinal, renal, cardiac and peripheral vascular complications were independent predictors related to early mortality in women. Conclusions: Women with CS showed a differential demographic and clinical profile and worse early outcomes than men. Advanced age, impaired consciousness, and medical complications were predictors of stroke severity in women with CS.

The Utility of Echocardiogram in the Workup of Ischemic Stroke Patients

BACKGROUND

Cardiac sources of emboli can be identified by transthoracic echocardiogram (TTE). The Canadian Best Practice Guidelines recommend routine use of TTE in the initial workup of ischemic stroke when an embolic source is suspected. However, TTEs are commonly ordered for all patients despite insufficient evidence to justify cost-effectiveness. We aim to evaluate the TTE ordering pattern in the initial workup of ischemic stroke at a regional Stroke Center in Central South Ontario and determine the proportion of studies which led to a change in management and affected length of stay (LOS).

METHODS

Hospital records of 520 patients with a discharge diagnosis of TIA or ischemic stroke between October 2016 and June 2017 were reviewed to gather information.

RESULTS

477 patients admitted for TIA or ischemic stroke met inclusion criteria. 67.9% received TTE, out of which 6.0% had findings of cardiac sources of emboli including left ventricular thrombus, atrial septal aneurysm, PFO, atrial myxoma, and valvular vegetation. 2.5% of all TTE findings led to change in medical management. The median LOS of patients who underwent TTE was 2 days longer (p < 0.00001).

CONCLUSION

TTE in the initial workup of TIA or ischemic stroke remains common practice. The yield of TTEs is low, and the proportion of studies that lead to changes in medical management is minimal. TTE completion was associated with increased LOS and may result in increased healthcare spending; however, additional factors prolonging the LOS could not be excluded.

Predictive utility of stress tests in the detection of asymptomatic coronary artery disease in atherosclerotic stroke patients

INTRODUCTION

Whether and how atherosclerotic ischemic stroke patients should be investigated for asymptomatic coronary artery disease (CAD) is controversial. Our aim was to carry out a prospective observational study to determine the frequency and predictors of functionally significant coronary stenosis in these patients as well as the predictors of major adverse cardiovascular events (MACE) during post-stroke follow-up.

MATERIAL AND METHODS

From January 2014 to June 2018, patients with atherosclerotic ischemic stroke were referred from the stroke unit to our cardiovascular department 3+/- 1 months after the acute event where they benefited from evaluation of cardiovascular risk factors, vascular and myocardial disease. Main outcome was defined as the prevalence of myocardial ischemia defined by perfusion stress echography 3 months after stroke. Secondary outcome (MACE) was defined as the incidence of stroke, transient ischemic attack (TIA), acute coronary syndrome, cardiovascular (CV) death or coronary or peripheral revascularization during a 3 year follow-up.

RESULTS

Three hundred and twenty five patients (92% of strokes and 8% TIA) were included and median follow-up was 1075 days. At 3 months post-stroke, myocardial ischemia was found in 17 patients (5.2%). During the 3 year follow-up, 11 MACE occurred (3.4%, all in the non-ischemic group) of which 6 were recurrent strokes. In multivariate analysis, myocardial ischemia was significantly associated with the number of atheromatous vascular beds (OR 4.3; 95% CI, 1.7 to 10.6) and ECG signs of necrosis (OR 6.5; 95% CI, 1.9 to 21.9). MACE were also associated with ECG signs of necrosis (OR 3.5; 95% CI, 1.3 to 9.1), and unrelated to myocardial ischemia.

CONCLUSION

Myocardial ischemia and CV events were infrequent and both strongly associated with ECG signs of necrosis, suggesting a low yield of stress tests and the potential for a more straightforward algorithm in the choice of patients eligible to coronary angiogram or other coronary imaging in post-stroke setting.

Diagnostic Yield of TEE in Patients with Cryptogenic Stroke and TIA with Normal TTE: A Systematic Review and Meta-Analysis

INTRODUCTION

The role of transesophageal echocardiography (TEE) in cryptogenic stroke and transient ischemic attack (TIA) with normal transthoracic echocardiography (TTE) remains controversial in the absence of definite guidelines. We aimed to perform a systematic review and meta-analysis to estimate an additional diagnostic yield and clinical impact of TEE in patients with cryptogenic stroke and TIA with normal TTE.

METHODS

We performed a systematic review of cohort studies on PubMed using the keywords 'cryptogenic stroke', cryptogenic TIA', 'TEE', and 'TTE' with matching MeSH terms. We included studies with patients who had cryptogenic stroke or TIA and had normal TTE findings, where the study intended to obtain TEE on all patients and reported all TEE abnormalities. The studies containing patients with atrial fibrillation were excluded. All studies were evaluated for internal and external validity. Inverse variance random effects models were used to calculate the effect size, the number needed to diagnose, and the 95% confidence interval.

RESULTS

We included 15 studies with 2054 patients and found LA/LAA/aortic thrombus, valvular vegetation, PFO-ASA, valvular abnormalities, and complex aortic plaques on TEE. Of these, 37.5% (29.7%-45.1%) of patients had additional cardiac findings on TEE. Management of 13.6% (8.1%-19.1%) of patients had changed after TEE evaluation. Based on current guidelines, it should change management in 4.1% (2.1%-6.2%) of patients and could potentially change management in 30.4% (21.9%-38.9%) of patients. Sensitivity analysis was also performed with only class II studies to increase internal validity, which showed additional cardiac findings in 38.4% (28.5%-48.3%), changed management in 20.2% (8.7%-31.8%), should change management in 4.7% (1.5%-7.9%), and could potentially change management in 30.4% (17.8%-43.0%) of patients.

CONCLUSIONS

The diagnostic yield of TEE to find any additional cardiac findings in patients with cryptogenic stroke or TIA is not only high, but it can also change management for certain cardiac abnormalities. TTE in cryptogenic stroke or TIA may mitigate future risks by tailoring the management of these patients.

Left Atrial Enlargement on Non-Gated CT Is Associated with Large Vessel Occlusion in Acute Ischaemic Stroke

Background

Recent reports have suggested that atrial fibrillation (AF) is more prevalent in the large vessel occlusion (LVO) subgroup of acute ischaemic stroke patients. Given the association between left atrial enlargement (LAE) and AF, we sought to evaluate the feasibility of assessing LAE on non-gated CT and its association with LVO in the hyperacute stroke setting.

Methods

We analysed our prospectively collected database that included all stroke patients referred for consideration of endovascular treatment between April 14, 2020, and May 21, 2020. During this period, a CT chest was included in our regional stroke protocol to aid triage of patients suspected for COVID-19 from which cardiac measurements were obtained. Patients were dichotomized into LVO and no-LVO groups, and LA measurements were trichotomized into normal, borderline, and enlarged. Univariate analyses were performed between groups.

Results

Of the included 38 patients, 21 were categorized as LVO and 17 as no LVO. There was a statistically significant association between LAE and LVO (p = 0.028). No significant difference was demonstrated between groups for the baseline AF and other clinical characteristics, except for baseline NIHSS (p = 0.0005). There was excellent inter- and intra-rater reliability (ICC = 0.969) for LA measurements.

Conclusion

Our study provides preliminary data to suggest LAE is more prevalent in the LVO stroke subgroup at presentation and can be reliably assessed on non-gated CT in the hyperacute setting. These findings have potential implications for stratifying secondary management and may prompt a more rigorous pursuit of occult AF or other cardiac causes of stroke.

Cardiovascular thrombotic complications in acute ischemic stroke assessed by chest spectral computed tomography during COVID-19

During the pandemic context, diagnostic algorithms had to be adapted considering the decimated medical personnel, local technical resources, and the likelihood of contamination. Given the higher probability of thrombotic complications related to COVID-19 and the availability of a dual-layer spectral computed tomography (CT) scanner, we have recently adopted the use of low-dose, non-gated, chest CT scans performed five minutes after contrast administration among patients admitted with acute ischemic stroke (AIS) undergoing cerebrovascular CT angiography. Dual-layer spectral CT comprises a single X-ray source and two-layer detector with different photon-absorption capabilities. In addition to conventional images, the two distinct energy datasets obtained enable multiparametric spectral analysis without need to change the original scanning protocol. The two spectral features that emerge as most useful for patients with AIS are virtual monoenergetic imaging and iodine-based results. Aside from the evaluation of lung parenchyma, this novel strategy enables ruling out cardioembolic sources and simultaneously providing evidence of pulmonary and myocardial injury in a single session and immediately after CT cerebrovascular angiography. Furthermore, it involves a non-invasive, seemingly accurate, unsophisticated, safer (very low radiation dose and no contrast administration), and cheaper tool for ruling out cardioembolic sources compared to transesophageal echocardiogram and cardiac CT. Accordingly, we sought to standardize the technical aspects and overview the usefulness of delayed-phase, low-dose chest spectral CT in patients admitted with AIS.

The Impact of Covariates in Voxel-Wise Lesion-Symptom Mapping

Background: Voxel-wise lesion-symptom mapping (VLSM) is a statistical technique to infer the structure-function relationship in patients with cerebral strokes. Previous VLSM research suggests that it is important to adjust for various confounders such as lesion size to minimize the inflation of true effects. The aim of this work is to investigate the regional impact of covariates on true effects in VLSM. Methods: A total of 222 follow-up datasets of acute ischemic stroke patients with known NIH Stroke Scale (NIHSS) score at 48-h post-stroke were available for this study. Patient age, lesion volume, and follow-up imaging time were tested for multicollinearity using variance inflation factor analysis and used as covariates in VLSM analyses. Covariate importance maps were computed from the VLSM results by standardizing the beta coefficients of general linear models. Results: Covariates were found to have distinct regional importance with respect to lesion eloquence in the brain. Age has a relatively higher importance in the superior temporal gyrus, inferior parietal lobule, and in the pre- and post-central gyri. Volume explains more variability in the opercular area of the insula, inferior frontal gyrus, and caudate. Follow-up imaging time accounts for most of the variance in the globus pallidus, ventromedial- and dorsolateral putamen, dorsal caudate, pre-motor thalamus, and the dorsal insula. Conclusions: This is the first study investigating and revealing distinctive regional patterns of importance for covariates typically used in VLSM. These covariate importance maps can improve our understanding of the lesion-deficit relationships in patients and could prove valuable for patient-specific treatment and rehabilitation planning.

Atrial fibrillation trial to evaluate real-world procedures for their utility in helping to lower stroke events: A randomized clinical trial

Background

Enhancing detection of unrecognized atrial fibrillation among acute ischemic stroke patients is crucial for secondary stroke prevention.

Aim

To evaluate whether the detection rate of new atrial fibrillation in acute ischemic stroke patients without known atrial fibrillation could be improved by doing serial 12-lead electrocardiograms once daily for five days, compared with conventional 24-h Holter monitoring (24-h Holter).

Methods

We conducted a randomized clinical trial to compare the detection rates of paroxysmal atrial fibrillation between serial electrocardiograms versus 24-h Holter from October 2015 to October 2018 at six hospitals. Eligible participants were acute ischemic stroke patients with aged ≥65 years, with neither atrial fibrillation history nor any presence of atrial fibrillation on baseline electrocardiogram at admission. The primary outcome was newly detected electrocardiogram in the serial electrocardiograms and 24-h Holter group.

Results

Among 826 patients, baseline characteristics were similar between both groups. In the intention-to-treat analysis, there was no statistical difference between serial electrocardiograms versus 24-Holter to detect atrial fibrillation (8.4% vs. 6.9%; adjusted odds ratio 1.17, 95% confidence interval 0.69–2.01). Stepwise multivariate logistic regression revealed age ≥80 years and history of heart failure were associated with detection of paroxysmal atrial fibrillation whereas patients with lacunar infarction had lower odds for detection of paroxysmal atrial fibrillation.

Conclusions

Serial electrocardiograms had comparable detection rate of paroxysmal atrial fibrillation compared with 24-h Holter and might be a viable alternative to 24-h Holter as a first-line approach to survey for potential paroxysmal atrial fibrillation among elderly patients with acute ischemic stroke.

Clinical Trial Registration: URL https://clinicaltrials.gov/ct2/show/NCT02578979

Unique Identifiers: NCT02578979

Value of routine echocardiography in the management of stroke

BACKGROUND

Transthoracic echocardiography is routinely performed in patients with stroke or transient ischemic attack (TIA) to help plan secondary stroke management, but recent data evaluating its usefulness in this context are lacking. We sought to evaluate the value of echocardiography for identifying clinically actionable findings for secondary stroke prevention.

METHODS

We conducted a multicentre cohort study of patients admitted to hospital with stroke or TIA between 2010 and 2015 at 2 academic hospitals in Toronto, Ontario, Canada. Clinically actionable echocardiographic findings for secondary stroke prevention included cardiac thrombus, patent foramen ovale, atrial myxoma or valvular vegetation. We identified patient characteristics associated with clinically actionable findings using logistic regression.

RESULTS

Of the 1862 patients with stroke or TIA we identified, 1272 (68%) had at least 1 echocardiogram. Nearly all echocardiograms were transthoracic; 1097 (86%) were normal, 1 (0.08%) had an atrial myxoma, 2 (0.2%) had a valvular vegetation, 11 (0.9%) had a cardiac thrombus and 66 (5.2%) had a PFO. Patent foramen ovale was less likely among patients older than 60 years (adjusted odds ratio [OR] 0.34, 95% confidence interval [CI] 0.20-0.57), with prior stroke or TIA (adjusted OR 0.31, 95% CI 0.09-0.76) or with dyslipidemia (adjusted OR 0.39, 95% CI 0.15-0.84). Among the 130 patients with cryptogenic stroke who had an echocardiogram (n = 110), a PFO was detected in 19 (17%) on transthoracic echocardiogram.

INTERPRETATION

Most patients with stroke or TIA had a normal echocardiogram, with few having clinically actionable findings for secondary stroke prevention. Clinically actionable findings, specifically PFO, were more common in patients with cryptogenic stroke.

Limitations of transoesophageal echocardiogram in acute ischaemic stroke

Objective

The role of transoesophageal echocardiography (TOE) in identifying ischaemic stroke aetiology is debated. In 2018, the American Heart Association/American Stroke Association (AHA/ASA) issued class IIa recommendation for echocardiography, with the qualifying statement of use in cases where it will alter management. Hence, we sought to determine the rate at which TOE findings altered management in cases of confirmed ischaemic stroke.

Methods

We retrospectively analysed TOE cases with confirmed ischaemic stroke at our centre between April 2015 and February 2017. We defined a change in management as the initiation of anticoagulation therapy, antibiotic therapy or patent foramen ovale closure as a direct result of TOE findings.

Results

There were 185 patients included in this analysis; 19 (10%) experienced a change in management. However, only 7 of the 19 (4% of all subjects) experienced a change in management due to TOE findings. The remaining 12 were initiated on oral antigoagulation as a result of discoveries during routine workup, mainly atrial fibrillation on telemetry monitoring.

Conclusions

This work suggests an overuse of TOE and provides support for the 2018 AHA/ASA stroke guidelines, which recommend against the routine use of echocardiography in the work up of cerebrovascular accident due to a cardioembolic source.

Left atrial cross-sectional area is a novel measure of atrial shape associated with cardioembolic strokes

OBJECTIVE

Cardioembolic (CE) stroke carries significant morbidity and mortality. Left atrial (LA) size has been associated with CE risk. We hypothesised that differential LA remodelling impacts on pathophysiological mechanism of major CE strokes.

METHODS

A cohort of consecutive patients hospitalised with ischaemic stroke, classified into CE versus non-CE strokes using the Causative Classification System for Ischaemic Stroke were enrolled. LA shape and remodelling was characterised by assessing differences in maximal LA cross-sectional area (LA-CSA) in a cohort of 40 prospectively recruited patients with ischaemic stroke using three-dimensional (3D) echocardiography. Flow velocity profiles were measured in spherical versus ellipsoidal in vitro models to determine if LA shape influences flow dynamics. Two-dimensional (2D) LA-CSA was subsequently derived from standard echocardiographic views and compared with 3D LA-CSA.

RESULTS

A total of 1023 patients with ischaemic stroke were included, 230 (22.5%) of them were classified as major CE. The mean age was 68±16 years, and 464 (45%) were women. The 2D calculated LA-CSA correlated strongly with the LA-CSA measured by 3D in both end-systole and end-diastole. In vitro flow models showed shape-related differences in mid-level flow velocity profiles. Increased LA-CSA was associated with major CE stroke (adjusted relative risk 1.10, 95% CI 1.04 to 1.16; p<0.001), independent of age, gender, atrial fibrillation, left ventricular ejection fraction and CHA₂DS₂-VASc score. Specifically, the inclusion of LA-CSA in a model with traditional risk factors for CE stroke resulted in significant improvement in model performance with the net reclassification improvement of 0.346 (95% CI 0.189 to 0.501; p=0.00001) and the integrated discrimination improvement of 0.013 (95% CI 0.003 to 0.024; p=0.0119).

CONCLUSIONS

LA-CSA is a marker of adverse LA shape associated with CE stroke, reflecting importance of differential LA remodelling, not simply LA size, in the mechanism of CE risk.

Emergency management of stroke in the era of mechanical thrombectomy

Emergency management of stroke has been directed at the delivery of recombinant tissue plasminogen activator (tPA) in a timely fashion. Because of the many limitations attached to the delivery of tPA and the perceived benefits accrued to tPA, its use has been limited. Mechanical thrombectomy, a far superior therapy for the largest and most disabling strokes, large vessel occlusions (LVOs), has changed the way acute strokes are managed. Aside from the rush to deliver tPA, there is now a need to identify LVO and refer those patients with LVO to physicians and facilities capable of delivering urgent thrombectomy. Other parts of emergency department management of stroke are directed at identifying and mitigating risk factors for future strokes and at preventing further damage from occurring. We review here the most recent literature supporting these advances in stroke care and present a framework for understanding the role that emergency physicians play in acute stroke care.

Stroke in the elderly

Stroke remains the second leading cause of death in the world, and its prevalence is projected to rise in the United States and globally. The main driver for increased stroke prevalence is aging of the population; however, best evidenced-based strategies for stroke treatment and prevention are not always followed for older patients. Furthermore, considerable gaps in knowledge exist for stroke prevention and treatment in elderly and very elderly patients. In this chapter, we discuss various aspects of stroke care in the elderly, including the evidence that guides stroke prevention and treatment. We focus on the challenges in managing stroke in the very elderly including the paucity of data to guide management. The sections span the continuum of stroke care, from primary prevention to management of stroke complications. Finally, we highlight the most significant unanswered questions regarding stroke care in the elderly.

Evaluation and Acute Management of Ischemic Stroke in Infants and Children

PURPOSE OF REVIEW

This article provides an overview of stroke in neonates, infants, and children.

RECENT FINDINGS

Arterial ischemic stroke and cerebral venous sinus thrombosis are increasingly recognized in childhood as important causes of lifelong morbidity and mortality. Diagnosis of arterial ischemic stroke is frequently delayed, as acute neurologic deficits can be challenging to detect in the young child, and stroke is often not considered in the differential diagnosis. Neurologic sequelae following stroke are common, and strategies to minimize stroke size and optimize recovery are being developed. Recurrent arterial ischemic stroke is not uncommon, particularly in children with cerebral arteriopathy. Cerebral venous sinus thrombosis causes obstruction of venous outflow leading to venous infarcts. Complications include hemorrhagic conversion of infarcts and increased intracranial pressure. Without treatment, thrombus extension with increased symptoms is common. Robust guidelines of care that exist for adults do not exist for children, particularly for children with arterial ischemic stroke.

SUMMARY

The approach to stroke in infants and children can be informed by clinical experience in pediatric stroke and cerebral venous sinus thrombosis, the extensive literature on pediatric thrombosis, and extrapolation from data from adult patients.

Is transesophageal echocardiography needed for evaluating tissue-based transient ischemic attack?

Transient ischemic attack (TIA) is a warning signal for stroke. A comprehensive evaluation of TIA may reduce the risk for subsequent stroke. Data on the findings of cardiac evaluation with transesophageal echocardiography (TEE) in patients with TIA are sparse. Our aims were to determine the frequency of TEE performance and to investigate the findings of TEE in patients with TIA based on the new definition of TIA (i.e., transient neurological symptoms without evidence of infarction). During a 4-year period (2011-2014), 1071 patients (mean age, 70 ± 13 years; female, 49.7%) with TIA were included in a prospective study and evaluated. Of 1071 consecutive patients suffering from TIA, 288 patients (27%) underwent TEE. The median time between admission and TEE was 6 days. Patients with TIA who were evaluated by TEE were younger (67 vs. 71 years, P < 0.001) than those who were not evaluated by TEE. They had a higher rate of sensibility disturbance as a TIA symptom (39% vs. 31%, P = 0.012) but a lower rate of previous stroke (15% vs. 25%, P = 0.001) and atrial fibrillation (2% vs. 21%, P < 0.001) than those who did not. Foramen ovale was detected in 71 patients (25.7%), atrial septal aneurysm in 13 patients (4.6%), and severe atherosclerotic plaques (grade 4 and 5) in the aortic arch in 25 patients (8.7%). One patient (0.3%) had a fibroma detected by TEE. In 17 of the 288 patients (6%) who underwent TEE, the indication for anticoagulation therapy was based on the TEE results, and 1 patient with fibroma underwent heart surgery. During hospitalization, 7 patients experienced a subsequent stroke, and 27 patients had a recurrent TIA. At 3 months following discharge, the rates of readmission, stroke, recurrent TIA, and death were 19%, 2.7%, 4.2%, and 1.6%, respectively. The rates of mortality (0.9% vs. 1.8%, P = 0.7), stroke risk (1.9% vs. 3.0%, P = 0.8), and recurrent TIA (5.0% vs. 3.9%, P = 0.8) were similar in patients who underwent TEE and in those who did not. Performing TEE in patients with tissue-based TIA is helpful in detecting cardiac sources for embolism and may indicate for anticoagulation.

Recent advances in the management of transient ischemic attacks

Significant advances in our understanding of transient ischemic attack (TIA) have taken place since it was first recognized as a major risk factor for stroke during the late 1950's. Recently, numerous studies have consistently shown that patients who have experienced a TIA constitute a heterogeneous population, with multiple causative factors as well as an average 5–10% risk of suffering a stroke during the 30 days that follow the index event. These two attributes have driven the most important changes in the management of TIA patients over the last decade, with particular attention paid to effective stroke risk stratification, efficient and comprehensive diagnostic assessment, and a sound therapeutic approach, destined to reduce the risk of subsequent ischemic stroke. This review is an outline of these changes, including a discussion of their advantages and disadvantages, and references to how new trends are likely to influence the future care of these patients.

Atrial fibrillation trial to evaluate real-world procedures for their utility in helping to lower stroke events (AFTER-PULSE): Study protocol for a randomized controlled trial

Background

Enhancing detection of undiagnosed atrial fibrillation (AF) in hospitalized patients with a recent ischemic stroke is important because of the treatment implications; especially since presence of paroxysmal AF may not be picked up in a single 12-lead electrocardiogram (ECG) test. While several trials have shown improved detection of AF with prolonged ECG monitoring, this strategy is associated with relatively high cost, labor intensity, and patient inconvenience, thereby making it challenging to routinely implement in all hospitals. Fortunately, conventional 24-h Holter monitoring and repeated 12-lead ECGs are readily available to detect paroxysmal AF in all hospitals, but is unclear which is the better strategy for evaluating undiagnosed AF. The objective of his study is to conduct a randomized trial of serial 12-lead ECGs vs. 24-hour Holter monitoring in the detection of AF in ischemic stroke patients without known AF.

Methods and analysis

We plan to enroll 1200 participants from six hospitals in Taiwan. Patients will be eligible for enrollment if they are admitted for an acute ischemic stroke within 2 days, are ≥65 years of age, and have no known AF by history or on baseline ECG at admission. We will randomly assign participants in a 1:1 ratio to undergo daily 12-lead ECG once daily for 5 days (intervention group) or 24-h Holter monitoring (control group). Primary outcome is newly detected AF on a 12-lead ECG or AF lasting ≥30 s on Holter monitoring.

Trial registration number

ClinicalTrials.gov Identifier: NCT02578979.

Revision of Echocardiographic Indications and Findings in Neurologically Ill Patients

Background and Objective:

Little is known about the general indications for echocardiography and the prevalence of abnormalities detected by echocardiography in patients who are referred from a neurological department. Left ventricular hypertrabeculation/noncompaction (LVHT) is associated with neuromuscular disorders and embolism. The aim of the study was to assess the indications for echocardiography in patients from a neurological department and to review the cine-loops of the examinations in order to assess the frequency of abnormal echocardiographic findings with special regard to LVHT.

Methods and Results:

Included were 126 patients, 58 females (mean age 65 years). Indications were stroke (84%), heart failure (6%), endocarditis (6%) and arrhythmia (3%). The most frequent abnormalities were impaired relaxation (71%) and left ventricular wall thickening (63%). Females were older (68 vs. 62 years, p = 0.0214) and more frequently had normally sized left ventricles than males (98 vs. 88%, p = 0.0376). Patients ≥66 years more frequently had stroke as an indication (91 vs. 77%, p = 0.05), showed a thickened myocardium (72 vs. 53%, p = 0.0272), valvular abnormalities (52 vs. 13%, p = 0.0000) and impaired relaxation (86 vs. 54%, p = 0.0001) than patients <66 years.

LVHT was diagnosed in 3 patients; in one of them the diagnosis was already known. In 45% LVHT and in 38% left ventricular thrombus could neither be excluded nor established since the image quality was poor.

Conclusion:

Care should be taken to visualize the left ventricular apical regions when investigating patients referred from a neurologic department in order not to overlook LVHT and thrombi within the left ventricular apex.

Diagnostic Impact of Transesophageal Echocardiography in Patients with Acute Cerebral Ischemia

OBJECTIVES

Transesophageal echocardiography (TEE) is the diagnostic gold standard for the detection of structural heart diseases as potential sources of cardiac emboli in patients with acute cerebral ischemia. We sought to determine the diagnostic yield of TEE in patients with acute ischemic stroke or transient ischemic attack (TIA).

METHODS

We retrospectively analyzed consecutive patients with acute cerebral ischemia who were admitted to our hospital between October 2008 and December 2011. TEE reports were screened for detection of cardiac source of embolism judged by the recommendation to change medical management. We performed univariate and multivariate analyses to identify predictors of clinically relevant TEE findings among baseline characteristics.

RESULTS

Of 3314 patients with ischemic stroke or TIA, TEE was performed in 791 (24%) patients (mean age 64 ± 13 years, 589 [74%] ischemic stroke, 202 [26%] TIA). A potential cardioembolic source was found in 71 (9%) patients with patent foramen ovale with atrial septal aneurysm being the most common finding (24/71 patients, 34%). In multivariate analysis, peripheral vascular disease (OR 2.57; 95%CI 1.00-6.61), imaging evidence of infarction in multiple locations (OR 4.13; 95%CI 1.36-12.58), and infarction in the posterior circulation (OR 2.11; 95%CI 1.01-4.42) were associated with the identification of a potential cardioembolic source with TEE.

CONCLUSION

TEE identified a potential structural cardioembolic source in nearly 10% of our selected patient population with acute ischemic stroke or TIA, thus underlining its diagnostic value. Our data suggest that patients with hitherto unknown stroke etiology should be considered for additional TEE.

Patent foramen ovale

Patent foramen ovale (PFO) is the most common congenital heart abnormality of fetal origin and is present in approximately ∼25% of the worldwide adult population. PFO is the consequence of failed closure of the foramen ovale, a normal structure that exists in the fetus to direct blood flow directly from the right to the left atrium, bypassing the pulmonary circulation. PFO has historically been associated with an increased risk of stroke, the mechanism of which has been attributed to the paradoxical embolism of venous thrombi that shunt through the PFO directly to the left atrium. However, several studies have failed to show an increased risk of stroke in asymptomatic patients with a PFO, and the risk of stroke recurrence is low in patients who have had a stroke that may be attributed to a PFO. With the advent of transoesophageal and transthoracic echocardiography, as well as transcranial Doppler, a PFO can be routinely detected in clinical practice. Medical treatment with either antiplatelet or anticoagulation therapy is recommended. At the current time, closure of the PFO by percutaneous interventional techniques does not appear to reduce the risk of stroke compared to conventional medical treatment, as shown by three large clinical trials. Considerable controversy remains regarding the optimal treatment strategy for patients with both cryptogenic stroke and PFO. This Primer discusses the epidemiology, mechanisms, pathophysiology, diagnosis, screening, management and effects on quality of life of PFO.

The value of transesophageal echocardiography in the investigation and management of cryptogenic cerebral ischemia: a single-center experience

The diagnostic utility of transesophageal echocardiography (TEE) has often been challenged in patients with cryptogenic stroke (CS). We estimated the prevalence of different findings on TEE examination of CS patients, their impact on secondary stroke prevention and the presence of potential age or gender disparities. We reviewed all TEE examinations that were performed in a single echocardiography laboratory during a 7-year-old period to identify CS patients that underwent investigation with TEE. Of the 518 total TEE examinations, we identified 88 CS patients. TEE revealed abnormal findings in 69.3 % of them. Patent foramen ovale (PFO) and atrial septal aneurysm (ASA) were identified in 30.6 and 22.7 % of the patients. Ascending aorta and aortic arch atheromatosis was present in 26.1 % of the patients, with complex atheromatosis diagnosed in 14.7 % of them. Cardiac myxomas were uncovered in 2.3 %. Thrombi in the left atrium and in cardiac valves were reported in 3.4 and 2.3 % of the patients, respectively. Based on TEE findings, the therapeutic management would be very likely modified in 9.1 % of the patients. Subgroup analysis revealed no gender disparities on the prevalence of TEE findings and in secondary stroke prevention, while linear regression analyses revealed significant associations of age with the prevalence of PFO, ASA, aorta atheromatosis and complex aorta atheromatosis. TEE examination should be included in the diagnostic work-up of all CS patients, irrespective of age and gender status, since it can reveal potential sources of embolism and has a significant impact for secondary stroke prevention.

Diagnostic yield of emergency department arch-to-vertex CT angiography in patients with suspected acute stroke

BACKGROUND AND PURPOSE

Our aim was to investigate how often relevant diagnostic findings in an arch-to-vertex CTA scan, obtained specifically as part of the acute stroke CT protocol, are located in the head, neck, and upper chest regions.

MATERIALS AND METHODS

Radiology reports were reviewed in 302 consecutive patients (170 men, 132 women; median ages, 66 and 73 years, respectively) who underwent emergency department investigation of suspected acute stroke between January and July 2010. Diagnostic CTA findings relevant to patient management were recorded for the head, neck, and chest regions individually. Additionally, the contributions to the total CTA scan effective dose were estimated from each of the 3 anatomic regions by using the ImPACT CT Dose Calculator.

RESULTS

Of the 302 patients, 161 (54%) had relevant diagnostic findings in the head; 94 (31%), in the neck; and 4 (1%), in the chest. The estimated contributions to the total CTA scan dose from each body region, head, neck, and upper chest, were 14 ± 2%, 33 ± 5%, and 53 ± 6%, respectively.

CONCLUSIONS

Most clinically relevant findings are in the head and neck, supporting inclusion of these regions in arch-to-vertex CTA performed specifically in patients with acute stroke in the emergency department. Further studies are required to investigate extending the scan to the upper chest because only 1% of patients in our study had clinically relevant findings in the mediastinum, yet half the CTA effective dose was due to scanning in this region.

Controversies in cardioembolic stroke

OPINION STATEMENT

Cardioembolic (CE) stroke mechanisms account for a significant number of ischemic strokes; however, the true burden is likely underestimated. It is critically important to identify patients with CE strokes because these individuals have high recurrence rates and represent a subgroup of patients who may benefit from targeted therapy in the form of anticoagulation or device based treatments. Current guidelines offer recommendations for diagnosis and treatment of these patients; however, important questions remain. First, appropriate cardiac testing in the setting of CE must be individualized and the optimal duration of electrocardiographic monitoring to rule out atrial fibrillation (AF) is unclear. Second, risk stratification tools for AF remain understudied, and there is controversy about which anticoagulant agents are most appropriate. Lastly, important potential CE sources of stroke such as patent foramen ovale have garnered significant attention recently, and debate regarding how to manage these patients persists. In this review, we discuss some of the important controversies in diagnosing and treating patients with possible CE stroke, pointing to areas where future research might be particularly valuable.

A role for human brain pericytes in neuroinflammation

BACKGROUND

Brain inflammation plays a key role in neurological disease. Although much research has been conducted investigating inflammatory events in animal models, potential differences in human brain versus rodent models makes it imperative that we also study these phenomena in human cells and tissue.

METHODS

Primary human brain cell cultures were generated from biopsy tissue of patients undergoing surgery for drug-resistant epilepsy. Cells were treated with pro-inflammatory compounds IFNγ, TNFα, IL-1β, and LPS, and chemokines IP-10 and MCP-1 were measured by immunocytochemistry, western blot, and qRT-PCR. Microarray analysis was also performed on late passage cultures treated with vehicle or IFNγ and IL-1β.

RESULTS

Early passage human brain cell cultures were a mixture of microglia, astrocytes, fibroblasts and pericytes. Later passage cultures contained proliferating fibroblasts and pericytes only. Under basal culture conditions all cell types showed cytoplasmic NFκB indicating that they were in a non-activated state. Expression of IP-10 and MCP-1 were significantly increased in response to pro-inflammatory stimuli. The two chemokines were expressed in mixed cultures as well as cultures of fibroblasts and pericytes only. The expression of IP-10 and MCP-1 were regulated at the mRNA and protein level, and both were secreted into cell culture media. NFκB nuclear translocation was also detected in response to pro-inflammatory cues (except IFNγ) in all cell types. Microarray analysis of brain pericytes also revealed widespread changes in gene expression in response to the combination of IFNγ and IL-1β treatment including interleukins, chemokines, cellular adhesion molecules and much more.

CONCLUSIONS

Adult human brain cells are sensitive to cytokine challenge. As expected 'classical' brain immune cells, such as microglia and astrocytes, responded to cytokine challenge but of even more interest, brain pericytes also responded to such challenge with a rich repertoire of gene expression. Immune activation of brain pericytes may play an important role in communicating inflammatory signals to and within the brain interior and may also be involved in blood brain barrier (BBB) disruption . Targeting brain pericytes, as well as microglia and astrocytes, may provide novel opportunities for reducing brain inflammation and maintaining BBB function and brain homeostasis in human brain disease.

How predictors and patterns of stroke recurrence after a TIA differ during the first year of follow-up

The highest risk of subsequent stroke after a TIA occurs within the first week after the index event. However, the risk of stroke recurrence (SR) remains high during the first year of follow-up. We studied the temporal pattern and predictors of SR (at 7 days and from 7 days to 1-year follow-up). Between April 2008 and December 2009, we included 1,255 consecutive TIA patients from 30 Spanish stroke centers (PROMAPA study). We determined the short-term (at 7 days) and long-term (from 8 days to 1 year) risk of SR. Patients who underwent short-term recurrence and long-term recurrence were compared with regard to clinical findings, vascular territories, and etiology. Enough information (clinical variables and extracranial vascular imaging) was assessed in 1,137 (90.6 %) patients. The 7-day stroke risk was 2.6 %. 32 (3.0 %) patients had an SR after 7-day follow-up. Multiple TIA (HR 3.50, 1.67-7.35, p = 0.001) and large artery atherosclerosis (HR 2.51, 1.17-5.37, p = 0.018) were independent predictors of early SR, whereas previous stroke (HR 1.40, 1.03-1.92, p = 0.034) and coronary heart disease (2.65, 1.28-5.50, p = 0.009) were independent predictors of late SR. Notoriously, 80 % of SR happened in the same territory of the index TIA at 7-day follow-up, whereas only 38 % during the long-term follow-up (p < 0.001). Different predictors of SR were identified throughout the follow-up period. Moreover, the ischemic mechanism differed in early and late stroke recurrences.

Approach to acute ischemic stroke in childhood

OPINION STATEMENT

Acute ischemic stroke in childhood is a medical emergency. Prompt recognition and intervention is necessary to rescue potentially viable brain tissue, prevent complications, and minimize the risk of recurrent stroke. Conditions that could result in recurrent stroke such as cardiac thrombus or cervical artery dissection need to be identified and treated promptly. Although the care of childhood stroke is based largely on extrapolation from adults, an organized approach to the care of these children is critical to optimize outcome.

Acute cardioembolic cerebral infarction: answers to clinical questions

Cardioembolic cerebral infarction (CI) is the most severe subtype of ischaemic stroke but some clinical aspects of this condition are still unclear. This article provides the reader with an overview and up-date of relevant aspects related to clinical features, specific cardiac disorders and prognosis of CI. CI accounts for 14-30% of ischemic strokes; patients with CI are prone to early and long-term stroke recurrence, although recurrences may be preventable by appropriate treatment during the acute phase and strict control at follow-up. Certain clinical features are suggestive of CI, including sudden onset to maximal deficit, decreased level of consciousness at onset, Wernicke's aphasia or global aphasia without hemiparesis, a Valsalva manoeuvre at the time of stroke onset, and co-occurrence of cerebral and systemic emboli. Lacunar clinical presentations, a lacunar infarct and especially multiple lacunar infarcts, make cardioembolic origin unlikely. The most common disorders associated with a high risk of cardioembolism include atrial fibrillation, recent myocardial infarction, mechanical prosthetic valve, dilated myocardiopathy and mitral rheumatic stenosis. Patent foramen ovale and complex atheromatosis of the aortic arch are potentially emerging sources of cardioembolic infarction. Mitral annular calcification can be a marker of complex aortic atheroma in stroke patients of unkown etiology. Transthoracic and transesophageal echocardiogram can disclose structural heart diseases. Paroxysmal atrial dysrhythmia can be detected by Holter monitoring. Magnetic resonance imaging, transcranial Doppler, and electrophysiological studies are useful to document the source of cardioembolism. In-hospital mortality in cardioembolic stroke (27.3%, in our series) is the highest as compared with other subtypes of cerebral infarction. Secondary prevention with anticoagulants should be started immediately if possible in patients at high risk for recurrent cardioembolic stroke in which contraindications, such as falls, poor compliance, uncontrolled epilepsy or gastrointestinal bleeding are absent. Dabigatran has been shown to be non-inferior to warfarin in the prevention of stroke or systemic embolism. All significant structural defects, such as atrial septal defects, vegetations on valve or severe aortic disease should be treated. Aspirin is recommended in stroke patients with a patent foramen ovale and indications of closure should be individualized. CI is an important topic in the frontier between cardiology and vascular neurology, occurs frequently in daily practice, has a high impact for patients, and health care systems and merits an update review of current clinical issues, advances and controversies.

Cardiovascular MRI in Detection and Measurement of Aortic Atheroma in Stroke/TIA patients

Background

Aortic Atheroma (AoA) is an independent risk factor for new and recurrent stroke. AoA ulceration and mobility are associated with an increased risk for brain embolism. Transesophageal echocardiography (TEE) is the gold standard for detection and measurement of AoA in stroke/TIA patients. Cardiovascular MRI (cMRI) could be an alternative, non-invasive imaging modality for stroke/TIA patients. The objective of this study was to assess the accuracy and correlation of AoA detected and measured by cMRI versus TEE in patients with recent stroke/TIA.

Methods and results

Twenty-two stroke/TIA patients undergoing TEE as a part of their stroke workup consented to a protocol-mandated cMRI performed on a 1.5 T magnet. The protocol included an axial non-breathhold EKG-gated dual-echo spin echo MRI of the thoracic aorta (TR/TE1/TE2=900/29/69) and a contrast-enhanced breathhold 3D gradient-echo image of the thorax (flip/TR/TE=12/4.0/1.71). Maximum plaque thickness, ulceration (≥ 2 mm) and mobility of AoA were assessed in the proximal (ascending and proximal arch) and distal (distal arch and descending) segments of thoracic aorta by a cardiologist to interpret the TEE and a radiologist to interpret the cMRI. There was good correlation between cMRI and TEE in measurement of plaque thickness in the proximal segments (R=0.73, p<0.0001) and the distal segments (R=0.81, p<0.0001) of the aortic arch (AA). cMRI had a high degree of accuracy in detecting measurable AoA (≥ 1 mm) in the proximal segments (sensitivity 90%, specificity 100%), as well as the distal segments (sensitivity 67%, specificity 100%). cMRI also had a high degree of accuracy in detecting significant AoA (≥ 4 mm) in proximal segments (sensitivity 71%, specificity 93%), as well as distal segments (sensitivity 71%, specificity 100%).

Conclusion

The study showed a high degree of accuracy and correlation of AoA detected and measured by cMRI as compared to TEE in patients with recent stroke/TIA. This technique has limitations in detection of AoA ulceration, and protocols assessing AoA mobility need to be developed.

Cardiac workup of ischemic stroke

Stroke is the leading cause of disability in developed countries and the third cause of mortality. Up to 15-30% of ischemic strokes are caused by cardiac sources of emboli being associated with poor prognosis and high index of fatal recurrence. In order to establish an adequate preventive strategy it is crucial to identify the cause of the embolism. After a complete diagnostic workup up to 30% of strokes remain with an undetermined cause, and most of them are attributed to an embolic mechanism suggesting a cardiac origin.There is no consensus in the extent and optimal approach of cardiac workup of ischemic stroke. Clinical features along with brain imaging and the study of the cerebral vessels with ultrasonography or MRI/CT based angiography can identify other causes or lead to think about a possible cardioembolic origin.Atrial fibrillation is the most common cause of cardioembolic stroke. Identification of occult atrial fibrillation is essential. Baseline ECG, serial ECG('s), cardiac monitoring during the first 48 hours, and Holter monitoring have detection rates varying from 4 to 8% each separately. Extended cardiac monitoring with event loop recorders has shown higher rates of detection of paroxysmal atrial fibrillation.Cardiac imaging with echocardiography is necessary to identify structural sources of emboli. There is insufficient data to determine which is the optimal approach. Transthoracic echocardiography has an acceptable diagnostic yield in patients with heart disease but transesophageal echocardiography has a higher diagnostic yield and is necessary if no cardiac sources have been identified in patients with cryptogenic stroke with embolic mechanism.

Echocardiographic assessment of hypertensive left ventricular hypertrophy in patients with acute ischemic stroke or transient ischemic attack

BACKGROUND

Hypertensive left ventricular hypertrophy (HLVH) is a major risk factor for cardiovascular morbidity, mortality, and stroke. However, little is known about the importance of transthoracic echocardiography (TTE) in the assessment of HLVH in patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA).

METHODS

We studied 203 consecutive patients admitted to our hospital with AIS or TIA and who were referred for TTE over the last 4 years. We included 102 (50.2%) lacunar strokes, 76 (37.1%) nonlacunar strokes, and 25 (12.3%) TIAs. The mean age was 68.9 years (standard deviation ± 11) and 128 patients were male (63.1%).

RESULTS

Hypertension was the most common risk factor (131 patients; 64.5%). HLVH was seen in 86 cases (42.3%), in 51.9% of patients with previous hypertension, and in 25% of patients without known hypertension. We found that neither stroke subtype nor any previous risk factor, with the exception of hypertension (P = .0001), were associated with HLVH. Patients with HLVH were younger (67 v 71 yrs; P = .013) and more frequently women (50.6% v 37.5%; P = .078). At discharge, patients with HLVH were more likely to receive antihypertensive treatment (97% v 80%; P = .009) and a higher average number of antihypertensive drugs (2.2 v 1.4; P = .0001).

CONCLUSIONS

HLVH was common in patients with AIS or TIA. These individuals had an increased risk of stroke and needed a more intensive therapy. TTE should be carried out in all AIS and TIA patients in order to optimize the management of these patients.