Letter by Mulder et al Regarding Article, "2015 AHA/ASA Focused Update of the 2013 Guidelines for the Early Management of Patients With Acute Ischemic Stroke Regarding Endovascular Treatment: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association"

Increased incidence of napkin-ring sign plaques on cervicocerebral computed tomography angiography associated with the risk of acute ischemic stroke occurrence

OBJECTIVES

Carotid atherosclerosis plays an essential role in the occurrence of ischemic stroke. This study aimed to investigate whether a larger burden of napkin-ring sign (NRS) plaques on cervicocerebral computed tomography angiography (CTA) increased the risk of acute ischemic stroke (AIS).

METHODS

This retrospective, single-center, cross-sectional study enrolled patients with NRS plaques identified in the subclavian arteries, brachiocephalic trunk, carotid arterial system, and vertebrobasilar circulation on contrast-enhanced cervicocerebral CTA. Patients were divided into AIS and non-AIS groups based on imaging within 12 h of symptom onset. Univariate and multivariate logistic regression analyses were performed to determine the risk factor of AIS occurrence.

RESULTS

A total of 202 patients (66.72 years ± 8.97, 157 men) were evaluated. Plaques with NRS in each subject of the AIS group (N = 98) were significantly more prevalent than that in the control group (N = 104) (1.96 ± 1.17 vs 1.41 ± 0.62). In the AIS group, there were substantially more NRS plaques on the ipsilateral side than contralateral side (1.55 ± 0.90 vs. 0.41 ± 0.66). NRS located on the ipsilateral side of the AIS showed an area under the receiver curve (AUC) of 0.86 to identify ischemic stroke. NRS plaque amounts were an independent risk factor for AIS occurrence (odds ratio, 1.86) after adjusting for other factors.

CONCLUSIONS

Increased incidence of napkin-ring sign plaques on cervicocerebral CTA was positively associated with AIS occurrence, which could aid in detecting asymptomatic atherosclerotic patients at high risk of AIS in routine screening or emergency settings.

CLINICAL RELEVANCE STATEMENT

Napkin-ring sign plaque provides an important imaging target for estimating acute ischemic stroke risk and identifying high-risk patients in routine screening or emergency settings, so that timely anti-atherosclerotic therapy can be used for prevention.

KEY POINTS

• This cross-sectional study investigated the association between high-risk carotid artery plaques and acute ischemic stroke. • Increased incidence of napkin-ring sign plaques on cervicocerebral computed tomography angiography is positively associated with acute ischemic stroke occurrence. • Napkin-ring signs help identify risky patients prone to acute ischemic stroke to facilitate prevention.

Efficacy of Solitaire AB stent-release angioplasty in acute middle cerebral artery atherosclerosis obliterative cerebral infarction

BACKGROUND

In both national and international studies, the safety and effectiveness of treatment with the Solitaire stent in patients with ischemic stroke caused by acute large vessel occlusion were good, and the disability rate was significantly reduced. However, there are currently only a few reports on the differences in endovascular treatment for different etiological classifications, especially in the anterior cranial circulation, aorta atherosclerotic stenosis, and acute thrombosis.

AIM

To investigate the efficacy of Solitaire AB stent-release angioplasty in patients with acute middle cerebral artery atherosclerosis obliterative cerebral infarction.

METHODS

Twenty-five patients with acute middle cerebral atherosclerosis obliterative cerebral infarction were retrospectively enrolled in this study from January 2017 to December 2019. The Solitaire AB stent was used to improve anterior blood flow to maintain modified cerebral infarction thrombolysis [modified thrombolysis in cerebral infarction (mTICI)] at the 2b/3 level or above, the stent was then unfolded and released.

RESULTS

All 25 patients underwent successful surgery, with an average recanalization time of 23 min. One patient died of cerebral hemorrhage and cerebral herniation after the operation. The National Institutes of Health Stroke Scale (NIHSS) scores immediately after surgery (7.5 ± 5.6), at 24 h (5.5 ± 5.6) and at 1 wk (3.6 ± 6.7) compared with the preoperative NIHSS score (15.9 ± 4.4), were significantly different (P < 0.01). One case of restenosis was observed 3 mo after surgery (the stenosis rate was 50% without clinical symptoms), the modified Rankin scale scores were 0 points in 14 cases (56%), 1 point in 4 cases (16%), 2 points in 2 cases (8%), 3 points in 3 cases (12%), 4 points in 1 case (4%), and 6 points in 1 case (4%).

CONCLUSION

In acute middle cerebral artery atherosclerosis obliterative cerebral infarction, when the Solitaire AB stent is unfolded and the forward blood flow is maintained at mTICI level 2b/3 or higher, stent release may be a safe and effective treatment method; however, long-term observation and a larger sample size are required to verify these findings.

Flat Panel CT Scanning Is Helpful in Predicting Hemorrhagic Transformation in Acute Ischemic Stroke Patients Undergoing Endovascular Thrombectomy

Purpose

Hyperdense lesions are frequently revealed on flat panel CT (FP-CT) immediately after endovascular thrombectomy in patients with acute ischemic stroke. This study is aimed at discriminating hyperdense lesions caused by extravasation plus hemorrhage from those caused by contrast extravasation alone.

Methods

We retrospectively analyzed clinical and radiological data of patients who underwent an immediate postprocedure FP-CT scan and a follow-up noncontrast CT 24 hours after thrombectomy. We especially focused on the Maximum Hounsfield Units (HU_max) of each hyperdense lesion. A hyperdense lesion was judged to be hemorrhagic when it persisted on noncontrast CT and/or developed a mass effect.

Results

Of 81 patients included in this study, 32 (39.5%) patients presented 41 hyperdense lesions on FP-CT. The chance of hemorrhagic transformation is higher in patients with hyperdense lesions on FP-CT than that in patients without hyperdense lesions (23/32 vs. 1/49, p < 0.001). The HU_max of hyperdensity on FP-CT can predict hemorrhagic transformation with an area under the curve of 0.805 (95% CI: 0.67-0.94, p = 0.02). The sensitivity, specificity, positive, and negative predictive values of hyperdensity on FP-CT for hemorrhagic transformation were 96%, 84%, 72%, and 98%, respectively. A HU_max of >600 predicted hemorrhagic transformation with a sensitivity of 50% and a specificity of 100%.

Conclusions

The presence of hyperdensity on FP-CT can predict hemorrhagic transformation with a high sensitivity and negative predictive value. The measurement of HU_max of hyperdense lesion on FP-CT can be applied to the management of patients undergoing endovascular recanalization.

Mechanical Thrombectomy in Acute Ischemic Stroke Patients Performed Within and Outside Clinical Trials in the United States

BACKGROUND

A better understanding of differences in outcomes of mechanical thrombectomy performed within and outside clinical trials will assist in optimal implementation of the procedure for acute ischemic stroke patients in general practice.

OBJECTIVE

To identify differences in demographic and clinical characteristics and outcomes related to mechanical thrombectomy in patients treated within clinical trials and those treated outside clinical trials in a large national cohort.

METHODS

We compared the patient characteristics and associated in-hospital outcomes of mechanical thrombectomy in acute ischemic stroke patients performed within and outside clinical trials using the Nationwide Inpatient Sample from 2013 to 2015. We analyzed in-hospital mortality (primary outcome) and moderate to severe disability (secondary outcome) based on discharge disposition after adjusting for potential confounders.

RESULTS

Of 23 375 patients who underwent mechanical thrombectomy, 430 (1.8%) underwent the procedure as part of a clinical trial. After adjusting for age, gender, and the teaching status of the hospital, patients treated within a clinical trial had lower rates of in-hospital mortality (odds ratio [OR] 0.14; 95% CI .03 to .71; P < .001). Among patients discharged alive, the rate of moderate to severe disability (OR .43; 95% CI .26 to .71; P < .001) was lower among those patients treated within a clinical trial. There was no difference in odds of post-thrombectomy intracerebral or subarachnoid hemorrhage between the two groups.

CONCLUSION

Mechanical thrombectomy performed as part of clinical trials was associated with lower rates of in-hospital mortality and lower rates of moderate to severe disability compared with those performed outside clinical trials.

Factors affecting in-hospital delay of intravenous thrombolysis for acute ischemic stroke: A retrospective cohort study

This study was designed to investigate the factors affecting the in-hospital delay of intravenous thrombolysis (IVT) for acute ischemic stroke (AIS).Two hundred and forty-eight consecutive AIS patients treated with intravenous administration of alteplase in Gansu Provincial Hospital from December 2014 to August 2018 were enrolled retrospectively in this study. According to door-to-needle (DTN) time, the patients were divided into either a delay group (DTN time > 60 minutes; n = 184) or a non-delay group (DTN time ≤60 minutes; n = 64). The baseline data, laboratory tests, onset-to-door (OTD) time, door-to-accepting time (DTA), door-to-imaging time (DTI), and decision-making time in both groups were recorded. Multivariate logistic analysis was performed to analyze the data.There were significant differences in previous history of cerebral ischemic attack, emergency system admission, education degree of decision makers, annual income, admission National Institutes of Health Stroke Scale (NIHSS), OTD time, DTA time, decision-making time between the 2 groups (all P < .05). Other baseline data and clinical features showed no significant difference between 2 groups (P > .05). Multivariate logistic regression analysis revealed that the risk of in-hospital delay was lower for the higher NIHSS score (OR = 0.775, 95% CI: 0.644-0.933, P = .007), the longer OTD time (OR = 0.963, 95% CI: 0.937-0.991, P = .010), the shorter decision-making time (OR = 1.224, 95% CI: 1.004-1.492, P = .045).This study suggested that NIHSS score, OTD time and decision-making time are the independent factors affecting the in-hospital delay of IVT for AIS.

Efficacy of Sonothrombolysis Using Microbubbles Produced by a Catheter-Based Microfluidic Device in a Rat Model of Ischemic Stroke

Limitations of existing thrombolytic therapies for acute ischemic stroke have motivated the development of catheter-based approaches that utilize no or low doses of thrombolytic drugs combined with a mechanical action to either dissolve or extract the thrombus. Sonothrombolysis accelerates thrombus dissolution via the application of ultrasound combined with microbubble contrast agents and low doses of thrombolytics to mechanically disrupt the fibrin mesh. In this work, we studied the efficacy of catheter-directed sonothrombolysis in a rat model of ischemic stroke. Microbubbles of 10-20 µm diameter with a nitrogen gas core and a non-crosslinked albumin shell were produced by a flow-focusing microfluidic device in real time. The microbubbles were dispensed from a catheter located in the internal carotid artery for direct delivery to the thrombus-occluded middle cerebral artery, while ultrasound was administered through the skull and recombinant tissue plasminogen activator (rtPA) was infused via a tail vein catheter. The results of this study demonstrate that flow focusing microfluidic devices can be miniaturized to dimensions compatible with human catheterization and that large-diameter microbubbles comprised of high solubility gases can be safely administered intraarterially to deliver a sonothrombolytic therapy. Further, sonothrombolysis using intraarterial delivery of large microbubbles reduced cerebral infarct volumes by approximately 50% vs. no therapy, significantly improved functional neurological outcomes at 24 h, and permitted rtPA dose reduction of 3.3 (95% CI 1.8-3.8) fold when compared to therapy with intravenous rtPA alone.

Targeted homing of CCR2-overexpressing mesenchymal stromal cells to ischemic brain enhances post-stroke recovery partially through PRDX4-mediated blood-brain barrier preservation

Rationale: Mesenchymal stromal cells (MSCs) are emerging as a novel therapeutic strategy for the acute ischemic stroke (AIS). However, the poor targeted migration and low engraftment in ischemic lesions restrict their treatment efficacy. The ischemic brain lesions express a specific chemokine profile, while cultured MSCs lack the set of corresponding receptors. Thus, we hypothesize that overexpression of certain chemokine receptor might help in MSCs homing and improve therapeutic efficacy. Methods: Using the middle cerebral artery occlusion (MCAO) model of ischemic stroke, we identified that CCL2 is one of the most highly expressed chemokines in the ipsilateral hemisphere. Then, we genetically transduced the corresponding receptor, CCR2 to the MSCs and quantified the cell retention of MSC^CCR2 compared to the MSC^dtomato control. Results: MSC^CCR2 exhibited significantly enhanced migration to the ischemic lesions and improved the neurological outcomes. Brain edema and blood-brain barrier (BBB) leakage levels were also found to be much lower in the MSC^CCR2-treated rats than the MSC^dtomato group. Moreover, this BBB protection led to reduced inflammation infiltration and reactive oxygen species (ROS) generation. Similar results were also confirmed using the in vitro BBB model. Furthermore, genome-wide RNA sequencing (RNA-seq) analysis revealed that peroxiredoxin4 (PRDX4) was highly expressed in MSCs, which mainly contributed to their antioxidant impacts on MCAO rats and oxygen-glucose deprivation (OGD)-treated endothelium. Conclusion: Taken together, this study suggests that overexpression of CCR2 on MSCs enhances their targeted migration to the ischemic hemisphere and improves the therapeutic outcomes, which is attributed to the PRDX4-mediated BBB preservation.

A Retrospective Study of Clinical Outcomes After Endovascular Treatment in Acute Ischemic Stroke Patients with Complete Anterior Circulation Infarction in the Absence of Multimodal Computed Tomography

OBJECTIVE

To analyze the positive predictive value of large artery occlusion and clinical prognosis in acute ischemic stroke patients with total anterior circulation infarct (TACI) who underwent endovascular treatment in the absence of multimodal CT angiography or CT perfusion.

METHODS

The inclusion criteria for the acute ischemic stroke patients to receive endovascular treatment were as the follows: the Oxfordshire Community Stroke Project classification was TACI, Alberta Stroke Program Early Computed Tomography Score (ASPECTS) ≥ 6, National Institutes of Health stroke scale (NIHSS) score ≥8, and less than 4.5 hours since stroke onset. The endovascular treatment was performed on patients who met the inclusion criteria. The endovascular treatment included intra-arterial thrombolysis, mechanical treatments, or both. A retrospective analysis was performed on all eligible acute ischemic stroke patients who underwent endovascular treatment from January 1, 2015 to December 31, 2015.

RESULTS

A total of 17 patients met the inclusion criteria and underwent endovascular treatment. The median age was 76 years (range, 59-88 years). 12 patients (70.6%) were diagnosed with atrial fibrillation. 16 patients were diagnosed with large artery occlusion by digital subtraction angiography, and the positive predictive value was 94.1%. 16 patients (94.1%) had recanalization (TICI Grade 3); 12 patients (70.6%) had a modified Rankin Scale score of 0-2, and 1 patient (5.9%) died 90 days after treatment.

CONCLUSIONS

In the absence of multimodal CT, endovascular treatment might be beneficial to patients with TACI acute ischemic stroke within 4.5 hours of stroke onset, who had NIHSS score of 8 or greater and ASPECTS of 6 or greater. These inclusion criteria have a high positive predictive value for anterior circulation large artery occlusion.

Neurons Over Nephrons: Systematic Review and Meta-Analysis of Contrast-Induced Nephropathy in Patients With Acute Stroke

BACKGROUND AND PURPOSE

Because of the perceived risk of contrast-induced acute kidney injury (AKI), many centers require pre-imaging serum creatinine levels, potentially delaying care. We performed a systematic review and meta-analysis evaluating AKI rates in patients with acute ischemic stroke receiving computed tomographic angiography (CTA) and computed tomographic perfusion (CTP).

METHODS

We searched MEDLINE, EMBASE, and the Web of Science through December 2016 for studies reporting on AKI in patients with acute ischemic stroke receiving CTA/CTP. Using a random-effects model, estimates were pooled across studies. Outcomes of interest were (1) the odds of AKI in patients receiving CTA/CTP versus noncontrast computed tomography, (2) overall rate of AKI and hemodialysis in patients with acute ischemic stroke undergoing CTA/CTP, and (3) the odds of CTA/CTP-associated AKI among patients with and without chronic kidney disease.

RESULTS

Fourteen studies were included (6 case-control studies and 8 single-arm studies) with 5727 CTA/CTP and 981 noncontrast computed tomography patients. In case-control studies, AKI was significantly lower among CTA/CTP patients compared with noncontrast computed tomography patients (odds ratio=0.47; 95% confidence interval=0.33-0.68; P<0.01). Adjusting for baseline creatinine, there was no difference in AKI rates between groups (odds ratio=0.34; 95% confidence interval=0.10-1.21). The overall rate of AKI in CTA/CTP patients was 3% (95% confidence interval=2%-4%). The overall rate of hemodialysis in the CTA/CTP group was 0.07% (3 of 4373). There was no difference in AKI among CTA/CTP patients with and without chronic kidney disease (odds ratio=0.63; 95% confidence interval=0.34-1.12).

CONCLUSIONS

Nonrandomized evidence suggests that CTA/CTP are not associated with statistically significant increase in risk of AKI in patients with stroke, even those with known chronic kidney disease.

Treatment in patients who are not eligible for intravenous alteplase: MR CLEAN subgroup analysis

Background and purpose

Patients with acute ischemic stroke due to intracranial large vessel occlusion benefit from intra-arterial therapy. Uncertainty exists about the effect of intra-arterial therapy in patients with contraindications for treatment with intravenous alteplase treatment. Our aim was to describe the clinical characteristics of this subgroup of patients and whether intra-arterial therapy is as safe and effective as it is after intravenous alteplase treatment.

Methods

All 500 MR CLEAN patients were included and we distinguished between patients who were and were not treated with intravenous alteplase treatment. We estimated the effect of intra-arterial therapy on the shift on the modified Rankin Scale score with ordinal logistic regression analysis and tested for interaction of intravenous alteplase treatment with intra-arterial therapy on outcome. Furthermore, safety parameters and serious adverse events were analyzed.

Results

Fifty-five patients (11%) were not treated with intravenous alteplase treatment, mostly because of prolonged coagulation time tests or recent surgery. These patients were older and more often had atrial fibrillation or other vascular comorbidity. There was no interaction between intravenous alteplase treatment and intervention effect ( p =  0.927). Intra-arterial therapy effect size in patients without intravenous alteplase treatment was 2.06 [95% CI: 0.69–6.13] and in patients with intravenous alteplase treatment 1.71 [95% CI: 1.22–2.40]. There were no safety issues.

Conclusions

For patients with acute ischemic anterior circulation stroke caused by intracranial large vessel occlusion, who have contraindications for intravenous alteplase, intra-arterial treatment is not less effective or less safe than in patients who receive the treatment after intravenous alteplase.

Clinical trial registration

Clinical trial registration-URL: http://www.trialregister.nl . Unique identifier: (NTR)1804. Clinical trial registration-URL: http://www.controlled-trials.com . Unique identifier: ISRCTN10888758.

Beliefs of Health Care Providers, Lay Health Care Providers and Lay Persons in Nigeria Regarding Hypertension. A Systematic Mixed Studies Review

BACKGROUND

Hypertension is a major health risk factor for mortality globally, resulting in about 13% of deaths worldwide. In Nigeria, the high burden of hypertension remains an issue for urgent attention. The control of hypertension, among other factors, is strongly determined by personal beliefs about the illness and recommended treatment.

OBJECTIVE

The aim of this review is to systematically synthesize available data from all types of studies on beliefs of the Nigerian populace about hypertension.

METHODS

We searched the following electronic databases; Medline, EMBase, PsycInfo, AMED from their inception till date for all relevant articles. A modified Kleinman's explanatory model for hypertension was used as a framework for extraction of data on beliefs about hypertension.

RESULTS

The search yielded a total of 3,794 hits from which 16 relevant studies (2 qualitative, 11 quantitative and 3 mixed methods studies) met the inclusion criteria for the review. Overall, most health care providers (HCPs) believe that stress is a major cause of hypertension. Furthermore, reported cut-off point for uncomplicated hypertension differed widely among HCPs. Lay Health Care Providers such as Patent Medicine Vendors' beliefs about hypertension seem to be relatively similar to health care professionals in areas of risk factors for hypertension, course of hypertension and methods of treatment. Among Lay persons, misconception about hypertension was quite high. Although some Nigerians believed that life style habits such as alcohol intake, exercise levels, cigarette smoking were risk factors for developing hypertension, there was discordance between belief and practice of control of risk factors. However, beliefs across numerous ethnic groups and settings (urban/rural) in Nigeria have not been explored.

CONCLUSION

In order to achieve control of hypertension in Nigeria, interventions should be informed, among other factors, by adequate knowledge of beliefs regarding hypertension across the numerous ethnic groups in Nigeria, settings (rural/urban), age and sex.