Editorial: Outcomes of stroke: prediction and improvement

Out of the 37 articles none seem to be on getting survivors 100% recovered, but you do have some predicting failure to recover. All in all, TOTALLY FUCKING USELESS!

Editorial: Outcomes of stroke: prediction and improvement

Heling ChSo of the 37 articlesu^1* Longxuan Li² Bin Qiu³ Yuping Tang⁴

• ¹Department of Gerontology, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
• ²Department of Neurology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
• ³School of Medicine, Yale University, New Haven, CT, United States
• ⁴Department of Neurology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China

Editorial on the Research Topic
Outcomes of stroke: prediction and improvement

Stroke remains the second-leading cause of death and the third-leading cause of disability worldwide (1). Of the two types of strokes, ischemic and hemorrhagic, the former accounts for more than 80% of strokes, while the latter is more disabling and fatal. Despite ongoing efforts to explore effective management and prevention strategies, the annual number and burden of stroke continue to grow worldwide, especially in low- and middle-income countries (2).

More and more attention has been paid to strategies that result in favorable outcomes for all types of strokes. Multiple therapies, including thrombolysis, mechanical thrombectomy, and surgical intervention, are used in clinical practice (3, 4). Despite the improvement in predictive ability, the choice of these therapies may be influenced by multiple factors, namely the time windows and may possibly bring out unpredictable adverse effects. Therefore, it will be more helpful if a predictor can rapidly identify the risks that affect the outcome and treatment effectiveness after stroke (5, 6). The management strategies chosen according to the effective prediction may provide more clinical benefits.

This Research Topic, entitled “Outcomes of Stroke: Prediction and Improvement,” aims to investigate the predictors and effective management strategies that can predict and improve stroke outcomes. It consists of 37 articles, and a brief description of the research findings follows.

As ischemic stroke accounts for more than 80% of strokes, most of the articles deal with the predictors and therapeutic strategies of ischemic stroke. Some of the works explore useful predictors of the outcomes of ischemic strokes. Liu et al. demonstrated that the ratio of vascular endothelial growth factor to CBP/P300-interacting transactivator with Glu/Asp-rich C-terminal domain 2 (VEGF/CITED2) from peripheral blood mononuclear cells is an independent protective factor and has a potential predictive value in the collateral circulation of acute ischemic stroke (AIS) evaluated by diffusion-weighted imaging (DWI)-Alberta Stroke Program Early CT Score (ASPECTS). Liu et al. showed that the ratio of serum uric acid to serum creatinine (SUA/SCr) is negatively associated with the risk of early neurological deterioration (END) within 1 week in patients with branch atheromatous disease stroke. Another study also investigated biomarkers of END. Wang Z. et al. detected plasma neurofilament light chain (pNFL) via a novel ultrasensitive single-molecule array and found that pNFL is a promising biomarker of END in minor stroke with large vessel occlusion. Meanwhile, Ag Lamat et al. illustrated how electroencephalogram (EEG) abnormalities are associated with stroke type and imaging characteristics. Additionally, NIHSS score and anterior circulation stroke can be considered predictors of focal EEG slowing.

Recurrent ischemic stroke (RIS) is associated with increased mortality and a poor outcome. Chung et al. investigated gender differences and risk factors for RIS. In their study, they found that hypertension and dyslipidemia were significant risk factors in both genders. Risk factors that differed between genders are smoking and alcohol consumption in men and diabetes in women. Another study by Wang H. et al. from Fudan University developed a radiomics-based DWI prediction model that performed well in terms of predicting 1-year RIS. Another prediction model for RIS was developed by Elhefnawy et al. from real-world data. In this model, incorporating time into predicting the risk of RIS can positively contribute to predicting the prognosis of RIS. The risk of RIS changes with time after the index ischemic stroke. In addition to concomitant diseases, secondary prevention time also plays a vital role in predicting the risk of RIS in the population. The COVID-19 pandemic has had a great impact on the treatment of AIS. Gu et al. demonstrated that the pandemic exacerbates certain time delays and plays a significant role in early adverse outcomes in patients with AIS. Atrial fibrillation (AF) is a common cardiac arrhythmia that is associated with an increased risk of ischemic stroke. Lu M. et al. performed a meta-analysis showing that the neutrophil-to-lymphocyte ratio (NLR), as an important inflammatory indicator, is associated with a higher risk of stroke in AF patients. The incidence of stroke in AF patients with NLR ≥3 was 1.4 times higher than in those with NLR <3. A comparative analysis performed by Bem Junior et al. showed that decompressive craniectomy is currently the most effective measure to control refractory ICH in cases of malignant ischemic stroke. In addition, Kosugi et al. conducted a study to create a cortical infarction using photothrombosis over the motor cortex of non-human primates to establish a reproducible deficit in the reaching and grasping tasks. This research suggests that different recovery speeds for each movement may be influenced by the extent to which cortical control is required to properly execute each movement.

Intravenous thrombolysis using recombinant tissue plasminogen activator (r-tPA) is effective for the treatment of AIS, although uncertainties remain about the balance of benefits and risks in some circumstances. In their study, Yuan et al. demonstrated that the non-standard dose of r-tPA (0.6 mg/kg ≤ dose < 0.9 mg/kg) does not differ in safety and effectiveness compared with the standard dose (0.9 mg/kg). The findings suggest that, according to current evidence and guidelines, the standard dose should be regarded as the first choice, while the above non-standard dose could be an alternative option in the actual diagnosis and treatment process, considering the patient's clinical profile and financial condition. Meanwhile, Xu et al. evaluated the safety and efficacy of low-dose alteplase (0.55–0.65 mg/kg) compared with standard-dose (0.85–0.95 mg/kg) in Chinese patients with AIS using a real-world registry. The results indicate that low-dose alteplase has a significantly higher rate of death or disability at discharge without reducing the risk of symptomatic intracranial hemorrhage. The prediction of outcome after intravenous thrombolytic therapy was also included in our Research Topic. Jiang et al. showed that the difference in red blood cell distribution width from before to after rt-PA thrombolysis is an independent predictor of neurological outcome at 2 years after thrombolysis in patients with AIS. Fekete et al.'s work implies that older age, higher NIHSS, large vessel occlusion, and intra-arterial thrombolysis may correlate with intracranial hemorrhage after thrombolytic therapy, and such patients always have unfavorable outcomes in a prospective single-center study. Norata et al. demonstrated that the liver fibrosis-4 score is associated with poor 3-month outcome and symptomatic intracranial hemorrhage in AIS patients undergoing intravenous thrombolysis.

Endovascular thrombectomy has been shown to be effective in the treatment of acute ischemic stroke in patients with large vessel occlusion (7). Prediction of prognosis, especially in patients with successful revascularization, is critical. Shao et al. demonstrated that acidosis, including decreased HCO−3

and pH levels detected by arterial blood gas (ABG) testing, is associated with clinical outcomes after endovascular therapy. Post-thrombectomy intracranial hemorrhage (PTIH) is a serious complication of AIS following mechanical thrombectomy. Rossi et al. analyzed 122 thrombi from 80 AIS patients and detected S100b expression by immunohistochemistry. The results show that S100b is co-localized with neutrophils, macrophages, and T-lymphocytes in clots and that higher S100b expression is associated with PTIH. In the study by Wagner et al., 714 AIS patients received intravenous thrombolysis followed by endovascular thrombectomy. Their results suggest that shorter intervals between intravenous thrombolysis and endovascular thrombectomy are associated with better 3-month functional outcomes. To reduce in-hospital workflow time, Zhou T. et al. developed a one-stop stroke management (OSSM) platform, and in their study, the OSSM transfer model significantly reduced the in-hospital delay in AIS patients compared to the traditional transfer model. Acute basilar artery occlusion (BAO) is one of the most fatal diseases, with a high risk of mortality and disability. Luo et al. aimed to determine the most effective rescue measure for acute BAO after the failure of mechanical thrombectomy. They found that balloon angioplasty, Wingspan stenting, and Apollo stenting rather than Solitaire stenting could be considered successful and safe rescue options. Lu Y. et al. investigated the optimal type of anesthesia management for acute vertebrobasilar artery occlusion (VBAO). Their findings reveal that similar effectiveness and safety were observed between general anesthesia (GA) and non-GA during endovascular treatment for VBAO, and GA may provide better successful reperfusion for a worse presenting GCS score (≤8). Another study by Lee et al. also examined the effects of anesthesia management for endovascular thrombectomy on outcomes through a meta-analysis of randomized clinical trials and trial sequence analysis. The conclusion is that patients with acute anterior circulation ischemic stroke who receive GA are associated with a higher rate of successful recanalization and a better 3-month neurological outcome compared to those who receive conscious sedation. A systematic review and meta-analysis conducted by Duan et al. aims to evaluate the current evidence on the feasibility, efficacy, and safety of endovascular thrombectomy in patients with active cancer. They found that such patients are likely to have an unfavorable outcome and that active cancer may increase the risk of mortality after endovascular thrombectomy. Another meta-analysis by Wu et al. revealed that the above-mentioned inflammatory marker NLR tested at admission and post-treatment can be used as a cost-effective and readily available biomarker to predict 3-month poor functional outcome, symptomatic intracerebral hemorrhage (sICH), and 3-month mortality in AIS patients undergoing reperfusion therapy. Hemorrhagic transformation is one of the most devastating complications of reperfusion therapy in AIS patients. A meta-analysis by Sun et al. identified several predictors of hemorrhagic transformation, including atrial fibrillation, a higher NIHSS score, older age, higher serum glucose levels, the number of thrombectomy procedures, and lower ASPECTS.

ICH accounts for ~10%−20% of all stroke subtypes with high mortality, and the survivors always have a high degree of residual disability. Hematoma expansion (HE) is often observed in the early stages of ICH, which independently predicts poor outcomes, namely death and disability (8). Qin et al. investigated the association between leukocyte subpopulations and HE according to two definitions (Definition 1: volume increase ≥6 ml or 33%; Definition 2: volume increase ≥12.5 ml or 33%). The findings revealed that a higher monocyte count is associated with a higher risk of HE regardless of the two definitions, whereas an increased neutrophil count is associated with a decreased risk of HE according to Definition 1. Shi et al. retrospectively analyzed 105 patients with severe basal ganglia ICH and demonstrated that NLR was a better predictor of 30-day mortality than other risk factors. In addition, a systematic review and meta-analysis by Li J. et al. showed that higher low-density lipoprotein cholesterol (LDL-C) levels may reduce the risk of mortality in ICH patients. Elevated LDL-C levels are only inversely associated with 3-month mortality risks, not in-hospital mortality risks in these patients. The study by Coleman et al. enrolled 2,449 patients from the ERICH trial to reveal that the SAVED2 score, which is composed of several common predictors, is associated with unfavorable outcomes in patients with ICH. Finally, Li Z. et al. presented a review summarizing recent advances in therapeutic strategies and directions for ICH and discussing the barriers and issues that need to be overcome to improve the prognosis of ICH. Subarachnoid hemorrhage (SAH) is another devastating type of hemorrhagic stroke with high mortality and disability rates. Neuroinflammation is an important mechanism of injury after ICH (9). Zhang et al. included 3,173 aneurysmal SAH (aSAH) patients and compared the predictive effects of multiple inflammatory markers. The results indicated that one of these inflammatory markers, the neutrophil-to-albumin ratio (NAR) could improve the SAFIRE and SAHIT models for 3-month mortality. Furthermore, Ji et al. demonstrated that increased serum anion gap (AG) is an independent, significant, and robust predictor of all-cause in-hospital mortality. Venous thrombosis is another rare form of stroke. Zhou et al. contributed a review that provided a reference for a comprehensive understanding of venous thrombosis and a scientific understanding of various pathophysiological mechanisms and clinical features related to this condition.

Several articles in our Research Topic concern both ischemic and hemorrhagic stroke. Zhao et al. analyzed the data of 1,601 stroke patients and found that inflammatory biomarkers such as NLR, NAR, and the ratio of red cell distribution width to albumin (RA) were able to predict 30-day mortality in hemorrhagic stroke but not in ischemic stroke. Matuja et al. investigated the predictors of 30-day mortality in patients with stroke in northwestern Tanzania. Their findings suggested that NIHSS and mRS on admission, aspiration pneumonia, and electrocardiogram abnormalities were associated with 30-day mortality. Importantly, Zhu et al. used several highly interpretable machine learning models to predict stroke prognosis with the highest accuracy to date and to identify heterogeneous treatment effects of warfarin and human albumin in stroke patients.

Overall, the current Research Topic of 37 articles provides a comprehensive overview of the latest advances in this field. It includes neuroimaging and body fluid markers that predict stroke outcomes. Moreover, the articles also include the latest developments in medical and surgical therapies that improve stroke outcomes(NOT DELIVER RECOVERY! Don't you think that, just maybe, survivors want to recover? Not just improve?). These findings may provide new insights for clinical practice. Further efforts are needed to investigate more beneficial therapeutic strategies, perhaps with the help of effective predictors.

TAS Test: Online Motor-cognitive Tests for Early Detection of Alzheimer's Disease (TASTest)

Does your doctor have enough brains and competence to be following this closely?

TAS Test: Online Motor-cognitive Tests for Early Detection of Alzheimer's Disease (TASTest)

Sponsor:

University of Tasmania

Collaborators:

National Health and Medical Research Council, Australia

University of Sydney

University of Leeds

Information provided by (Responsible Party):

Jane Alty, University of Tasmania

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Study Description

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Brief Summary:

Global dementia prevalence is rising. Alzheimer's disease (AD), the most common cause, has devastating effects on people's quality of life. AD has a preclinical (pre-AD) period of 10-20 years when brain pathology silently progresses before any cognitive symptoms appear. Current tests for pre-AD are invasive, costly and unsuitable for screening at population level. Similar to screening for pre-diabetes and carcinoma in situ, it is important to detect AD at the preclinical stage in order to offer early interventions before the pathology progresses to the irrerversible degenerative stage. In the study, research will develop a new scalable test (TAS Test) by combining two innovative ideas: hand-movement tests to detect pre-AD >10 years before cognitive symptoms begin; and computer vision so people can "self-test" online using home computers. This unique approach builds on recent discoveries that hand-movement patterns change in pre-AD. The research team will use exquisitely precise computer vision methods to automatically analyse movement data from thousands of participants, and combine this with machine learning of overall motor-cognitive performance. The project team has access to 3 well-phenotyped cohorts, >10,000 existing participants and a cutting-edge assay for a blood AD biomarker, ptau181. The research team will develop a TAS Test algorithm to classify hand-movement and cognitive test data for pre-AD risk (p-taua181 levels) and determine TAS Test's precision to prospectively predict 5-year risks of cognitive decline and AD.

Condition or disease	Intervention/treatment
Alzheimer Disease Dementia Age-related Cognitive Decline	Diagnostic Test: Cognitive test scores, clinical diagnosis and blood biomarkers

Detailed Description:

Sub-study 1: Cross-sectional study design: From two established cohorts with pre-existing datasets of up to 10 years of longitudinal cognitive, genetic and demographic data, the team will recruit 500 participants over 50 years old who are confirmed to have normal cognition. At baseline and months 3 and 6, the participants will be invited to complete TAS Test online at home, or in the research centre if preferred. The participants will also have a baseline blood test for ptau181 levels (and APOE4 if required). The research team will integrate movement data to develop a multivariable model that discriminates between pre-AD (positive p-tau181) and normal cognitive ageing (negative p-tau181).

Sub-study 2: Prospective 5-year cohort study design: The researchers will invite 10,000 adults from an established long-term (ISLAND Project) cohort to complete online tests at home: (i) TAS Test every 6 months, and (ii) Cambridge Neuropsychological Test Automated Battery (CANTAB) cognitive tests every 24 months. The prospective 'high risk' predictions of TAS Test at baseline will be validated against CANTAB scores, and also clinically (face to face gold standard consensus diagnosis of AD vs MCI vs normal) in a subsample of 300.

Study Design

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Study Type :	Observational
Estimated Enrollment :	3000 participants
Observational Model:	Cohort
Time Perspective:	Prospective
Official Title:	TAS Test: Determining the Feasibility and Validity of Online Motor-cognitive Testing for Early Detection of Alzheimer's Disease
Actual Study Start Date :	March 5, 2021
Estimated Primary Completion Date :	December 2025
Estimated Study Completion Date :	December 2030

The TAS Test project: a prospective longitudinal validation of new online motor-cognitive tests to detect preclinical Alzheimer’s disease and estimate 5-year risks of cognitive decline and dementia

Ask your doctor if this is a valid test for stoke survivors. WHY DOES YOUR DOCTOR KNOW NOTHING ABOUT THIS? Maybe because they're incompetent?

The TAS Test project: a prospective longitudinal validation of new online motor-cognitive tests to detect preclinical Alzheimer’s disease and estimate 5-year risks of cognitive decline and dementia

• Jane Alty,
• Quan Bai,
• Renjie Li,
• Katherine Lawler,
• Rebecca J. St George,
• Edward Hill,
• Aidan Bindoff,
• Saurabh Garg,
• Xinyi Wang,
• Guan Huang,
• Kaining Zhang,
• Kaylee D. Rudd,
• Larissa Bartlett,
• Lynette R. Goldberg,
• Jessica M. Collins,
• Mark R. Hinder,
• Sharon L. Naismith,
• David C. Hogg,
• Anna E. King &
• James C. Vickers 

BMC Neurology volume 22, Article number: 266 (2022) Cite this article

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Abstract

Background

The worldwide prevalence of dementia is rapidly rising. Alzheimer’s disease (AD), accounts for 70% of cases and has a 10–20-year preclinical period, when brain pathology covertly progresses before cognitive symptoms appear. The 2020 Lancet Commission estimates that 40% of dementia cases could be prevented by modifying lifestyle/medical risk factors. To optimise dementia prevention effectiveness, there is urgent need to identify individuals with preclinical AD for targeted risk reduction. Current preclinical AD tests are too invasive, specialist or costly for population-level assessments. We have developed a new online test, TAS Test, that assesses a range of motor-cognitive functions and has capacity to be delivered at significant scale. TAS Test combines two innovations: using hand movement analysis to detect preclinical AD, and computer-human interface technologies to enable robust ‘self-testing’ data collection. The aims are to validate TAS Test to [1] identify preclinical AD, and [2] predict risk of cognitive decline and AD dementia.

Methods

Aim 1 will be addressed through a cross-sectional study of 500 cognitively healthy older adults, who will complete TAS Test items comprising measures of motor control, processing speed, attention, visuospatial ability, memory and language. TAS Test measures will be compared to a blood-based AD biomarker, phosphorylated tau 181 (p-tau181). Aim 2 will be addressed through a 5-year prospective cohort study of 10,000 older adults. Participants will complete TAS Test annually and subtests of the Cambridge Neuropsychological Test Battery (CANTAB) biennially. 300 participants will undergo in-person clinical assessments. We will use machine learning of motor-cognitive performance on TAS Test to develop an algorithm that classifies preclinical AD risk (p-tau181-defined) and determine the precision to prospectively estimate 5-year risks of cognitive decline and AD.

Discussion

This study will establish the precision of TAS Test to identify preclinical AD and estimate risk of cognitive decline and AD. If accurate, TAS Test will provide a low-cost, accessible enrichment strategy to pre-screen individuals for their likelihood of AD pathology prior to more expensive tests such as blood or imaging biomarkers. This would have wide applications in public health initiatives and clinical trials.

Trial registration

ClinicalTrials.gov Identifier: NCT05194787, 18 January 2022. Retrospectively registered.

Estimating presymptomatic episodic memory impairment using simple hand movement tests: A cross-sectional study of a large sample of older adults

Ask your doctor if this is a valid test for stoke survivors.

Estimating presymptomatic episodic memory impairment using simple hand movement tests: A cross-sectional study of a large sample of older adults

Xinyi Wang, Rebecca J. St George, Aidan D. Bindoff, Alastair J. Noyce, Katherine Lawler, Eddy Roccati, Larissa Bartlett, Son N. Tran, James C. Vickers, Quan Bai, Jane Alty

First published: 30 July 2023

https://doi.org/10.1002/alz.13401

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Abstract

INTRODUCTION

Finding low-cost methods to detect early-stage Alzheimer's disease (AD) is a research priority for neuroprotective drug development. Presymptomatic Alzheimer's is associated with gait impairment but hand motor tests, which are more accessible, have hardly been investigated. This study evaluated how home-based Tasmanian (TAS) Test keyboard tapping tests predict episodic memory performance.

METHODS

1169 community participants (65.8 ± 7.4 years old; 73% female) without cognitive symptoms completed online single-key and alternate-key tapping tests and episodic memory, working memory, and executive function cognitive tests.

RESULTS

All single-key (R²_adj = 8.8%, ΔAIC = 5.2) and alternate-key (R²_adj = 9.1%, ΔAIC = 8.8) motor features predicted episodic memory performance relative to demographic and mood confounders only (R²_adj = 8.1%). No tapping features improved estimation of working memory.

DISCUSSION

Brief self-administered online hand movement tests predict asymptomatic episodic memory impairment. This provides a potential low-cost home-based method for stratification of enriched cohorts.

Highlights

• We devised two brief online keyboard tapping tests to assess hand motor function.
• 1169 cognitively asymptomatic adults completed motor- and cognitive tests online.
• Impaired hand motor function predicted reduced episodic memory performance.
• This brief self-administered test may aid stratification of community cohorts.

1 BACKGROUND

Dementia prevalence is predicted to triple to more than 150 million globally by 2050.^{1, 2} Most cases are caused by Alzheimer's disease (AD), which has a 10- to 20-year presymptomatic period of “silent” brain pathology (amyloid beta and tau deposition) before episodic memory symptoms emerge.³ To reduce dementia prevalence, there is an urgent need to identify at-risk individuals for early interventions. Up to 40% of dementia cases are attributable to modifiable risk factors,⁴ and the recent emergence of monoclonal therapies for AD may be most efficacious earlier in the disease course.^{5, 6} Dementia prevention and drug development are hindered by the lack of accessible, cost-effective tests to identify “at-risk” cohorts for specialist assessments, early recruitment to clinical trials, and targeted interventions. Current methods, such as neuropsychological assessments, blood- and cerebrospinal fluid (CSF)-based biomarkers, and positron emission tomography (PET) scans are too expensive, time-consuming, or invasive.³

Motor analysis holds strong potential to identify people at risk of AD. Gait slows down, with less rhythmic stepping, about 10 years before dementia diagnosis,⁷ but the need for specialist movement-sensing equipment and fall risk are barriers for translation to a population-level test. Though less explored than gait, hand motor function also declines in presymptomatic AD and has the advantage of accessible assessments through computer keyboards.⁸ Two recent studies found slower and less rhythmic tapping features in mild cognitive impairment (MCI) and AD, but both required laboratory-based equipment.^{9, 10} In 2019, Mollica et al. evaluated hand motor function in 72 older adults and found the speed and rhythm of repeatedly tapping a single computer key discriminated those with presymptomatic AD (n = 20, CSF Aβ-positive) from those with negative CSF biomarkers (n = 37).⁸ These promising findings have not yet been replicated in other at-risk groups or in larger samples.

This study builds upon Mollica et al.’s study by designing a self-administered keyboard tapping test to measure hand motor function at home. We aimed to evaluate (i) whether a single-key tapping test would help identify subtly impaired cognitive performance in episodic memory in a large community cohort of older cognitively asymptomatic adults, over and above a model that includes age, education, sex, level of education, anxiety, and depression; (ii) how a single-key motor performance test would compare with a more challenging alternate-key tapping test (based on the Bradykinesia Akinesia Incoordination [BRAIN] tap test¹¹); and (iii) which combination of motor features would best predict cognitive performance.

We hypothesized that impaired hand motor performance (defined as slower tapping frequency, arrhythmia, inaccurate target, or prolonged dwell time on each key) would associate with impairments in episodic memory but not in cognitive domains less sensitive to early AD (working memory, executive dysfunction)¹² and that the alternate-key test would have a stronger association due to greater cognitive loads required for key switching.

 

More at link.

Calculated plasma volume status is associated with poor outcomes in acute ischemic stroke treated with endovascular treatment

You described a problem, offered NO solution. YOU'RE FIRED!

Calculated plasma volume status is associated with poor outcomes in acute ischemic stroke treated with endovascular treatment

Dixia Zhang Qiuru Li Jun Liu Lijuan Ma Jing Ye Guifen Hu Guangzong Li^*

• Department of Neurology, The Sixth People's Hospital of Chengdu, Chengdu, China

Background and purpose: The impact of calculated plasma volume status (PVS) on the prognosis of acute ischemic stroke treated with endovascular treatment (EVT) remains undetermined. This study aimed to investigate the association between PVS and 90 days functional outcomes after EVT.

Methods: We enrolled patients treated with EVT in the anterior circulation from a prospective registry. The endpoint was a modified Rankin scale score of ≥3 points at 90 days after EVT. We used multivariable logistic regression models to investigate the association between PVS and poor outcomes. We used the restricted cubic spline to present the linearity between PVS and poor outcomes.

Results: Among the 187 enrolled patients (median age, 65 years; 35.8% women), a total of 81 patients (43.3%) experienced poor outcomes at 90 days. In multivariable analyses, PVS was associated with poor outcomes despite increasing confounding factors (odds ratio, 3.157; 95% confidence interval, 1.942–5.534; P < 0.001). The restricted cubic spline revealed a positive correlation between PVS and the risk of poor outcomes after EVT (P for nonlinearity = 0.021).

Conclusion: Our study found that an elevated PVS value was associated with poor outcomes after EVT. Further prospective cohorts were warranted to evaluate the utility of PVS in AIS treated with EVT.

AdventHealth Gordon is nationally recognized for its commitment to providing high-quality stroke care

Anytime I see 'care' in any press release I know the hospital is not willing to disclose actual results because they are so fucking bad, it wouldn't look good, so misdirection is used. Don't fall for that misdirection!

Big fucking whoopee.

 

 But you tell us NOTHING ABOUT RESULTS. They remind us they 'care' about us multiple times but never tell us how many 100% recovered.  You have to ask yourself why they are hiding their incompetency by not disclosing recovery results.  ARE THEY THAT FUCKING BAD?

Three measurements will tell me if the stroke hospital is possibly not completely incompetent; DO YOU MEASURE ANYTHING?  I would start cleaning the hospital by firing the board of directors, you can't let incompetency continue for years at a time.

There is no quality here if you don't measure the right things.

1. tPA full recovery? Better than 12%?
2. 30 day deaths? Better than competitors?

3. rehab full recovery? Better than 10%?

 

You'll want to know results so call that hospital president(whomever that is) RESULTS are; tPA efficacy, 30 day deaths, 100% recovery. Because there is no point in going to that hospital if they are not willing to publish results.

In my opinion this cert allows stroke hospitals to continue with their tyranny of low expectations and justify their complete failure to get survivors 100% recovered. Prove me wrong, I dare you in my stroke addled mind. If your stroke hospital goal is not 100% recovery you don't have a functioning stroke hospital.

All you ever get from hospitals are that they are following guidelines; these are way too static to be of any use. With thousands of pieces of stroke research yearly it would take a Ph.D. level research analyst to keep up, create protocols, and train the doctors and therapists in their use. 

If your stroke hospital doesn't have that, you don't have a well functioning stroke hospital, you have a dinosaur. 

Read up on the guidelines yourself.

“What's measured, improves.” So said management legend and author Peter F. Drucker 

 The latest invalid chest thumping here:

 

AdventHealth Gordon is nationally recognized for its commitment to providing high-quality stroke care

Advent Health Gordon has received the American Heart Association’s Get With The Guidelines^® – Stroke Gold Plusquality achievement award for its commitment to ensuring stroke patients receive the most appropriate treatment according to nationally recognized, research-based guidelines, ultimately leading to more lives saved and reduced disability.

Stroke is the No. 5 cause of death and a leading cause of disability in the U.S. A stroke occurs when a blood vessel that carries oxygen and nutrients to the brain is either blocked by a clot or bursts. When that happens, part of the brain cannot get the blood and oxygen it needs, so brain cells die. Early stroke detection and treatment are key to improving survival, minimizing disability and accelerating recovery times.

Get With The Guidelines puts the expertise of the American Heart Association and American Stroke Association to work for hospitals nationwide, helping ensure patient care is aligned with the latest research- and evidence-based guidelines. Get With The Guidelines – Stroke is an in-hospital program for improving stroke care by promoting consistent adherence to these guidelines, which can minimize the long-term effects of a stroke and even prevent death.

AdventHealth Gordon also received the American Heart Association’s Target: Stroke^SM Honor RollElite Plusaward. To qualify for this recognition, hospitals must meet specific criteria that reduce the time between an eligible patient’s arrival at the hospital and treatment with the clot-buster alteplase. 

In addition, AdventHealth Gordon was awarded the American Heart Association’s Target: Type 2 Diabetes Honor Roll award. Target: Type 2 Diabetes Honor Roll aims to ensure patients with Type 2 diabetes, who might be at higher risk for complications, receive the most up-to-date, evidence-based care when hospitalized due to stroke.

“AdventHealth Gordon is committed to providing the best patient care by adhering to the latest treatment guidelines,” said Chris Self, president and CEO of AdventHealth Gordon. “This award makes it easier for our teams to put proven knowledge and guidelines to work on a daily basis, which studies show can help patients recover better. Our goal is to ensure members of our community can experience longer, healthier lives and feel whole.”

“We are incredibly pleased to recognize AdventHealth Gordon for its commitment to caring for patients with stroke,” said Steven Messe, MD, volunteer chairperson of the American Heart Association Stroke System of Care Advisory Group and professor of neurology and director of fellowships of neurology at the Hospital of the University of Pennsylvania. “Participation in Get With The Guidelines is associated with improved patient outcomes, fewer readmissions and lower mortality rates – a win for health care systems, families and communities.”

###

About Get With The Guidelines^®Get With The Guidelines^® is the American Heart Association/American Stroke Association’s hospital-based quality improvement program that provides hospitals with the latest research-based guidelines. Developed with the goal of saving lives and hastening recovery, Get With The Guidelines has touched the lives of more than 12 million patients since 2001. For more information, visit heart.org.

University Hospitals nationally recognized for commitment to high-quality stroke care

Anytime I see 'care' in any press release I know the hospital is not willing to disclose actual results because they are so fucking bad, it wouldn't look good, so misdirection is used. Don't fall for that misdirection!

Big fucking whoopee.

 

 But you tell us NOTHING ABOUT RESULTS. They remind us they 'care' about us multiple times but never tell us how many 100% recovered.  You have to ask yourself why they are hiding their incompetency by not disclosing recovery results.  ARE THEY THAT FUCKING BAD?

Three measurements will tell me if the stroke hospital is possibly not completely incompetent; DO YOU MEASURE ANYTHING?  I would start cleaning the hospital by firing the board of directors, you can't let incompetency continue for years at a time.

There is no quality here if you don't measure the right things.

1. tPA full recovery? Better than 12%?
2. 30 day deaths? Better than competitors?

3. rehab full recovery? Better than 10%?

 

You'll want to know results so call that hospital president(whomever that is) RESULTS are; tPA efficacy, 30 day deaths, 100% recovery. Because there is no point in going to that hospital if they are not willing to publish results.

In my opinion this cert allows stroke hospitals to continue with their tyranny of low expectations and justify their complete failure to get survivors 100% recovered. Prove me wrong, I dare you in my stroke addled mind. If your stroke hospital goal is not 100% recovery you don't have a functioning stroke hospital.

All you ever get from hospitals are that they are following guidelines; these are way too static to be of any use. With thousands of pieces of stroke research yearly it would take a Ph.D. level research analyst to keep up, create protocols, and train the doctors and therapists in their use. 

If your stroke hospital doesn't have that, you don't have a well functioning stroke hospital, you have a dinosaur. 

Read up on the guidelines yourself.

“What's measured, improves.” So said management legend and author Peter F. Drucker 

 The latest invalid chest thumping here:

 

University Hospitals nationally recognized for commitment to high-quality stroke care

CLEVELAND — University Hospitals has received numerous American Heart Association/American Stroke Association Get With The Guidelines Stroke awards.

The awards demonstrate commitment to the latest, research-based guidelines for the treatment of stroke, ultimately leading to more lives saved, shorter recovery times and fewer readmissions to the hospital.

“University Hospitals is committed to improving care by adhering to the latest treatment guidelines and streamlining processes to ensure timely and proper care for patients with stroke,” said Dr. Cathy Sila, chair of the Department of Neurology at University Hospitals and Case Western Reserve University School of Medicine, and the Gilbert W. Humphrey Endowed Professor of Neurology.

“The Get With The Guidelines program makes it easier for our teams to put proven knowledge and guidelines to work daily, which helps us ensure more people in Cleveland and surrounding areas can live longer, healthier lives,” she said. “We are proud to be recognized for our efforts this year, and are especially proud of our rural hospitals who have made it a goal to ensure certain hurdles, like transportation times and staffing, do not affect the standard of care our patients receive.”

The awards recognize hospitals that demonstrate at least 85 percent compliance in each of the seven Get With The Guidelines- Stroke Achievement Measures. Tier levels are determined by the length of demonstrated performance.

The following local UH hospitals received these American Heart Association levels of achievement this year:

• Get With The Guidelines – Stroke Gold Plus and Target: Stroke Honor Roll

75 percent of applicable patients experiencing door to needle times of 60 minutes or less

· UH Geauga Medical Center, a campus of UH Regional Hospitals

· Western Reserve Hospital (a joint-venture hospital)

• Get With The Guidelines – Stroke Gold Plus

· UH Elyria Medical Center

· UH Geneva Medical Center

• Get with The Guidelines – Stroke Silver Plus

Silver recognizes performance of 12 consecutive months or more. Silver Plus awards are advanced levels of recognition acknowledging hospitals for consistent compliance with quality measures.

· UH Conneaut Medical Center

• Get With The Guidelines – Rural Stroke Bronze (new award category this year)

This award recognizes hospitals for their efforts toward acute stroke care excellence demonstrated by composite score compliance to guideline-directed care for intravenous thrombolytic therapy, timely hospital inter-facility transfer, dysphagia screening, symptom timeline and deficit assessment documentation, emergency medical services communication, brain imaging and stroke expert consultation.

· UH Conneaut Medical Center

· UH Geneva Medical Center

· UH Samaritan Medical Center

UH Ahuja, Cleveland, Elyria, Geauga, Geneva, Parma, Portage, Samaritan, and St. John medical centers, as well as Southwest General Health Center and Western Reserve Hospital received Target: Type 2 Diabetes℠ Honor Roll awards.

These awards recognize hospitals for providing the most up-to-date, evidence-based care for patients with type 2 diabetes who are hospitalized with heart failure, heart attack or stroke.

Las Palmas Del Sol Healthcare facilities receive national recognition for prioritizing quality care for stroke patients

Anytime I see 'care' in any press release I know the hospital is not willing to disclose actual results because they are so fucking bad, it wouldn't look good, so misdirection is used. Don't fall for that misdirection!

Big fucking whoopee.

 

 But you tell us NOTHING ABOUT RESULTS. They remind us they 'care' about us multiple times but never tell us how many 100% recovered.  You have to ask yourself why they are hiding their incompetency by not disclosing recovery results.  ARE THEY THAT FUCKING BAD?

Three measurements will tell me if the stroke hospital is possibly not completely incompetent; DO YOU MEASURE ANYTHING?  I would start cleaning the hospital by firing the board of directors, you can't let incompetency continue for years at a time.

There is no quality here if you don't measure the right things.

1. tPA full recovery? Better than 12%?
2. 30 day deaths? Better than competitors?

3. rehab full recovery? Better than 10%?

 

You'll want to know results so call that hospital president(whomever that is) RESULTS are; tPA efficacy, 30 day deaths, 100% recovery. Because there is no point in going to that hospital if they are not willing to publish results.

In my opinion this cert allows stroke hospitals to continue with their tyranny of low expectations and justify their complete failure to get survivors 100% recovered. Prove me wrong, I dare you in my stroke addled mind. If your stroke hospital goal is not 100% recovery you don't have a functioning stroke hospital.

All you ever get from hospitals are that they are following guidelines; these are way too static to be of any use. With thousands of pieces of stroke research yearly it would take a Ph.D. level research analyst to keep up, create protocols, and train the doctors and therapists in their use. 

If your stroke hospital doesn't have that, you don't have a well functioning stroke hospital, you have a dinosaur. 

Read up on the guidelines yourself.

“What's measured, improves.” So said management legend and author Peter F. Drucker 

 The latest invalid chest thumping here:

 

Las Palmas Del Sol Healthcare facilities receive national recognition for prioritizing quality care for stroke patients

Las Palmas Del Sol Healthcare facilities are being recognized by the American Heart Association and American Stroke Association for providing quality care to stroke patients.

Del Sol Medical Center and Las Palmas Medical Center received the associations’ Get With The Guidelines® – Stroke Gold Plus quality achievement award for their commitment to ensuring stroke patients receive the most appropriate treatment according to nationally recognized, research-based guidelines. Both facilities also received the Association’s Target: Stroke℠ Honor Roll Elite Plus award and Target: Type 2 Diabetes℠ Honor Roll award.

 

Stroke is the No. 5 cause of death and a leading cause of disability in the U.S. On average, someone in the U.S. suffers a stroke every 40 seconds, and nearly 795,000 people suffer a new or recurrent stroke each year. Early stroke detection and treatment are key to improving survival, minimizing disability and speeding recovery times.

 

Get With The Guidelines – Stroke was developed to assist healthcare professionals in providing the most up-to-date, research-based guidelines for treating stroke patients.

 

“We are committed to providing excellent care to all of our patients, including stroke patients, and we are proud to receive recognition for our efforts through the Get With The Guidelines program,” Don Karl, chief executive officer of Las Palmas Medical Center, said. “This achievement would not be possible without the extraordinary efforts of our doctors, nurses and staff.”

 

To earn the Get With The Guidelines Gold Plus award, Las Palmas Medical Center and Del Sol Medical Center achieved two or more consecutive calendar years of 85 percent or higher adherence to all guidelines. The hospital also achieved 75 percent or higher compliance with additional select quality measures in stroke.

 

“We are pleased to be recognized with multiple national awards for the care that we provide our stroke patients,” Art Garza, chief executive officer of Del Sol Medical Center, said. “We are grateful for the dedication our team provides to patients and for their ongoing commitment to improving the quality of care for all El Pasoans.”

 

To qualify for Target: Stroke Honor Roll Elite Plus recognition, hospitals must meet specific criteria developed to reduce the time between the patient’s arrival at the hospital and treatment with a clot-buster drug to treat ischemic stroke.

 

For the Target: Type Two Diabetes Honor Roll award, hospitals must aim to ensure patients with type two diabetes receive the most up-to-date, evidence-based care when hospitalized due to stroke.

 

To learn more about Get With The Guidelines – Stroke and its recognition criteria, please visit the American Heart Association’s website.

Cottage Health Nationally Recognized for Its Commitment to High-Quality Stroke Care

Anytime I see 'care' in any press release I know the hospital is not willing to disclose actual results because they are so fucking bad, it wouldn't look good, so misdirection is used. Don't fall for that misdirection!

Big fucking whoopee.

 

 But you tell us NOTHING ABOUT RESULTS. They remind us they 'care' about us multiple times but never tell us how many 100% recovered.  You have to ask yourself why they are hiding their incompetency by not disclosing recovery results.  ARE THEY THAT FUCKING BAD?

Three measurements will tell me if the stroke hospital is possibly not completely incompetent; DO YOU MEASURE ANYTHING?  I would start cleaning the hospital by firing the board of directors, you can't let incompetency continue for years at a time.

There is no quality here if you don't measure the right things.

1. tPA full recovery? Better than 12%?
2. 30 day deaths? Better than competitors?

3. rehab full recovery? Better than 10%?

 

You'll want to know results so call that hospital president(whomever that is) RESULTS are; tPA efficacy, 30 day deaths, 100% recovery. Because there is no point in going to that hospital if they are not willing to publish results.

In my opinion this cert allows stroke hospitals to continue with their tyranny of low expectations and justify their complete failure to get survivors 100% recovered. Prove me wrong, I dare you in my stroke addled mind. If your stroke hospital goal is not 100% recovery you don't have a functioning stroke hospital.

All you ever get from hospitals are that they are following guidelines; these are way too static to be of any use. With thousands of pieces of stroke research yearly it would take a Ph.D. level research analyst to keep up, create protocols, and train the doctors and therapists in their use. 

If your stroke hospital doesn't have that, you don't have a well functioning stroke hospital, you have a dinosaur. 

Read up on the guidelines yourself.

“What's measured, improves.” So said management legend and author Peter F. Drucker 

 The latest invalid chest thumping here:

 

Cottage Health Nationally Recognized for Its Commitment to High-Quality Stroke Care

SANTA BARBARA – Cottage Health has received two American Heart Association Get With The Guidelines® achievement awards for demonstrating a commitment to research-based guidelines for the treatment of stroke, leading to more lives saved, shorter recovery times and fewer readmissions to the hospital.

• Get With The Guidelines® – Stroke Gold Plus award with Target: Stroke Elite Honor Roll – Santa Barbara Cottage Hospital, recognized for ensuring stroke patients have access to best practices and life-saving care.
• Get With The Guidelines® – Stroke Rural Bronze recognition – Santa Ynez Valley Cottage Hospital, recognized for efforts to optimize stroke care and strive to eliminate rural health care outcome disparities.“We are proud our team is being recognized for the important work we do every day to improve the lives of people in Santa Barbara County and along the Central Coast who are affected by stroke, giving them the best possible chance of recovery and survival,” said Dr. Philip Delio, Medical Director of the Stroke Program at Cottage Health.Every 40 seconds, someone in the U.S. has a stroke or heart attack, and heart disease and stroke are the No. 1 and No. 5 causes of death in the United States, respectively. Studies show patients can improve recovery by consistently following treatment guidelines.Get With The Guidelines put the expertise of the American Heart Association and American Stroke Association to work for hospitals nationwide, helping ensure patient care is aligned with the latest evidence- and research-based guidelines. As Get with the Guideline participants, SBCH and SYCH qualified for the awards by demonstrating commitment to improving quality care.“We are pleased to recognize Cottage Health for its commitment to caring for those in their community who need cardiovascular care,” said John Warner, M.D., FAHA, past president of the American Heart Association and CEO of The Ohio State University Wexner Medical Center. “Hospitals that follow the American Heart Association’s quality improvement protocols often see improved patient outcomes, fewer readmissions and lower mortality rates – a win for health care systems, families and communities.”

Prescribe exercise for ‘dramatic impact’ on mortality, heart disease risk

Before your doctor can prescribe exercise they need to get you 100% recovered. So ask your doctor 'WHERE ARE THE 100% RECOVERY PROTOCOLS?' No answer, you don't have a functioning stroke doctor!

Prescribe exercise for ‘dramatic impact’ on mortality, heart disease risk

Key takeaways:

• The benefits of exercise occur at levels well below federal recommendations.
• Physical activity impacts mortality risk across ages, races and genders.

ARLINGTON, Texas — Physical fitness is a vital sign for overall health, and prescribing even small amounts of exercise to increase cardiorespiratory fitness can reduce mortality and CVD risk, according to a speaker.

The 2018 federal physical activity guidelines suggest 150 to 300 minutes per week of moderate physical activity or 75 minutes per week of vigorous physical activity, Carl “Chip” Lavie Jr., MD, FACC, FACP, FCCP, professor of medicine, medical director of cardiac rehabilitation and preventive cardiology, director of the Exercise Testing Laboratory and staff cardiologist in the Echocardiographic Laboratory at the John Ochsner Heart and Vascular Institute, Ochsner Clinical School–The University of Queensland School of Medicine, said during a presentation at the American Society for Preventive Cardiology Congress on CVD Prevention.

The benefits of exercise occur at levels well below federal recommendations.
Image: Adobe Stock

However, evidence suggests that exercise benefits occur even at levels far below those federal recommendations. Maximal health benefits occur at about 40 to 60 minutes per week of physical activity for “almost everyone;” with activities like running, maximal benefits occur at very low levels, Lavie said.

Carl “Chip” Lavie Jr.

“Regardless of whether you have a low or higher level of fitness, [data show] changes in your fitness over time had a dramatic impact on all-cause mortality,” Lavie said. “If you are fit, increasing your fitness more can have benefits long term.”

Heart benefits with increased fitness

Exercise and improved cardiorespiratory fitness provide many physiological benefits, Lavie said, including improved heart rate variability, reduced BP and systemic inflammation, improved insulin sensitivity and endothelial function and decreased myocardial oxygen demand. Exercise is also associated with reduced risk for development of hypertension, metabolic syndrome, type 2 diabetes, dementia and Alzheimer’s disease. There are also mental health benefits that have a downstream effect on CV and overall health, Lavie said.

“Physical activity and fitness have a tremendous impact on psychosocial stress,” Lavie said. “We have shown that improving this in the cardiac rehab setting is associated with reductions in mortality.”

In a retrospective analysis published in May 2022 in European Heart Journal – Quality of Care & Clinical Outcomes, Lavie and colleagues found that, among 853 patients with CHD referred to cardiac rehab who completed a maximal cardiopulmonary exercise test, peak VO₂ at the end of cardiac rehab was an independent predictor of long-term survival.

“The most important thing that predicted survival in our coronary patients was getting a higher end of cardiac rehab peak VO₂,” Lavie said. “Exercise capacity at the end of rehab was the strongest predictor of subsequent survival.”

Exercise ‘dose,’ frequency matter

Small, incremental changes can lead to health benefits for patients, Lavie said. For the biggest “bang for the buck,” clinicians should work to move patients out of a “low fitness” category — when they are at highest risk for CV events — into a mid-level fitness regimen by encouraging about 150 minutes per week of moderate levels of regular exercise, Lavie said.

“An exercise prescription involves information on intensity, frequency, duration and mode of exercise,” Lavie said. “The main mode recommended is aerobic exercise: walking or jogging on the treadmill or outside, bicycle, aerobic dance and swimming. Certainly, resistance exercises is needed as well, at least once or twice per week.”

To improve fitness, patients should aim to achieve about 65% to 85% of their maximum heart rate for a duration of about 15 to 20 minutes at a frequency of four to five times per week, Lavie said. Clinicians should caution patients to monitor the intensity level of any exercise regimen.

“Patients should be able to talk while they are exercising,” Lavie said. “If they can chat the entire time, they are probably not exercising hard enough. If they can’t talk at all, they are probably exercising too hard.”

Lavie said the promotion of physical activity and exercise training is needed throughout the health care system, particularly during the COVID-19 era.

“Every clinician that sees a patient should be telling them something about physical activity and documenting that in the medical record,” Lavie said.

References:

• Carbone S, et al. Eur Heart J Qual Care Clin Outcomes. 2022;doi:10.1093/ehjqcco/qcab032.
• Wen CP, et al. Lancet. 2011;doi:10.1016/S0140-6736(11)60749-6.

Hypercapnia increases brain viscoelasticity

 A cerebral blood flow increase of  36 ± 15% sounds like it could be very important immediately post stroke! It's been almost 4 years, has ANYTHING AT ALL been done in the stroke world on this? Or do we have fucking failures of stroke associations  doing nothing once again?

No clue, so ask your doctor what this means.

Viscoelasticity is defined as the time-dependent response of a material subjected to a constant load or deformation (Cohen, Foster, & Mow, 1998). From: Human Orthopaedic Biomechanics, 2022.

What is Hypercapnia?

 

Hypercapnia increases brain viscoelasticity

J Cereb Blood Flow Metab. 2019 Dec; 39(12): 2445–2455.

Published online 2018 Sep 5. doi: 10.1177/0271678X18799241

PMCID: PMC6893988

PMID: 30182788

Stefan Hetzer,^1,2 Florian Dittmann,³ Karl Bormann,^1,2 Sebastian Hirsch,^1,2 Axel Lipp,⁴ Danny JJ Wang,⁵ Jürgen Braun,⁶ and Ingolf Sack³

Author information Article notes Copyright and License information Disclaimer

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Abstract

Brain function, the brain’s metabolic activity, cerebral blood flow (CBF), and intracranial pressure are intimately linked within the tightly autoregulated regime of intracranial physiology in which the role of tissue viscoelasticity remains elusive. We applied multifrequency magnetic resonance elastography (MRE) paired with CBF measurements in 14 healthy subjects exposed to 5-min carbon dioxide-enriched breathing air to induce cerebral vasodilatation by hypercapnia. Stiffness and viscosity as quantified by the magnitude and phase angle of the complex shear modulus, |G*| and ϕ, as well as CBF of the whole brain and 25 gray matter sub-regions were analyzed prior to, during, and after hypercapnia. In all subjects, whole-brain stiffness and viscosity increased due to hypercapnia by 3.3 ± 1.9% and 2.0 ± 1.1% which was accompanied by a CBF increase of 36 ± 15%. Post-hypercapnia, |G*| and ϕ reduced to normal values while CBF decreased by 13 ± 15% below baseline. Hypercapnia-induced viscosity changes correlated with CBF changes, whereas stiffness changes did not. The MRE-measured viscosity changes correlated with blood viscosity changes predicted by the Fåhræus–Lindqvist model and microvessel diameter changes from the literature. Our results suggest that brain viscoelastic properties are influenced by microvessel blood flow and blood viscosity: vasodilatation and increased blood viscosity due to hypercapnia result in an increase in MRE values related to viscosity.

Results

Figure 3 shows group-averaged perfusion and stiffness maps of one representative image slice for the three phases of the hypercapnia challenge. Figure 4 shows the group-averaged values of whole-brain perfusion, stiffness, and viscosity next to the average values of BP and HR. All of them follow a similar pattern: (i) highly significant increase from normocapnia to hypercapnia: Δ|G*| = +3.3 ± 1.9% (p = 1.1 × 10⁻⁵), Δϕ = +2.0 ± 1.1% (p = 1.8 × 10⁻⁶), ΔCBF = + 36 ± 15% (p = 1.7 × 10⁻⁷), ΔBP = +3.4 ± 3.0% (p = 4.3 × 10⁻³), ΔHR = +5.1 ± 6.0% (p = 5.2 × 10⁻³); (ii) decrease after hypercapnia with significant differences for stiffness, viscosity, and perfusion only: Δ|G*| = −2.4 ± 1.9% (p = 3.9 × 10⁻⁴), ΔBP = −0.8 ± 3.7% (p = 4.5 × 10⁻¹), Δϕ = −2.0 ± 0.7% (p = 1.2 × 10⁻⁶), ΔHR = −2.3 ± 6.4% (p = 9.6 × 10⁻²), and ΔCBF = −36 ± 11% (p = 1.6 × 10⁻⁷). For an overview of all group-averaged whole-brain MRE and CBF values, see Table 1.

Figure 3.

Group-averaged perfusion, stiffness, and viscosity maps of one exemplary slice in Montreal Neurological Institute space for the three phases of the hypercapnia challenge. See Figure 2(b) for the corresponding map of analyzed AAL atlas regions in the same slice. Note the pronounced CBF offset in the auditory cortex activated by the scanner noise (Heschl’s gyrus—ROI #23, white arrow). CBF: cerebral blood flow.

Figure 4.

Highly significant increase in all parameters between normocapnia and hypercapnia (red). Decrease in all measured parameters after hypercapnia (blue) with significant differences for whole-brain perfusion, stiffness, and viscosity only (*p < 0.05; **p < 0.01; ***p < 0.001). Note the significant CBF drop under baseline (dashed line) after hypercapnia. For detailed values, see Table 1. CBF: cerebral blood flow.