Arterial stiffness and functional outcome in acute ischemic stroke

Advanced vascular aging and outcomes after acute ischemic stroke: a systematic review and meta-analysis

Pulse wave velocity (PWV) is as a reliable marker of arterial stiffness and vascular aging, surpassing traditional risk factors in predicting detrimental cardiovascular events. The present meta-analysis aims to investigate PWV thresholds and assess its prognostic value in outcomes of acute ischemic stroke (AIS). A search was conducted in PubMed, Cochrane, Web of Science, and Scopus for studies published up to January 2024, focusing on patients admitted with AIS, wherein arterial stiffness was assessed through PWV measurements during hospitalization. Identified studies reported PWV values in individuals with both favorable and unfavorable outcomes at the end of follow-up. Initially, 35 eligible studies provided data for weighted mean baPWV (11,953 AIS patients) and cfPWV (2,197 AIS patients) calculations. The average age was 67 years, with approximately 60% male, 67% hypertensive, 30% diabetic and 30% smoker participants. The weighted mean systolic blood pressure was approximately 150 mmHg. In AIS patients, the mean PWV was 10 m/s for standard cfPWV and 20 m/s for baPWV. Nine cohort studies (6,006 AIS patients) were included in the quantitative analysis of clinical outcomes. Higher PWV levels were associated with poorer functional outcomes (2.3 m/s higher, 95%CI:1.2-3.4, p < 0.001; I2 = 87.4%). AIS patients with arterial stiffness/vascular aging (higher PWV) had approximately 46.2% increased risk of poor functional outcome, 12.7% higher risk of mortality, 13.9% greater risk of major adverse cardiovascular events, and 13.9% greater risk of stroke recurrence over the long term compared to those without arterial stiffness. Advanced vascular aging, as indicated by PWV, significantly predicts adverse outcomes in AIS patients. Integrating the assessment of vascular aging into clinical practice can improve risk perception in these patients.

The Impact of Sex and Arterial Stiffness Interactions on the Outcome after an Acute Ischemic Stroke: A Retrospective Cohort Study

Background/Objectives: Arterial stiffness (AS) is an independent predictor of cardiovascular events and is associated with a poor prognosis. While AS may represent a novel therapeutic target, recent evidence shows that it is sexually dimorphic. The aim of this study was to evaluate relative sex differences in arterial stiffness and their possible impact on the outcome of acute ischemic stroke. Methods: We retrospectively evaluated a cohort of adult patients with the following inclusion criteria: acute ischemic stroke, which occurred within 24 h from the onset of symptoms, confirmed through neuroimaging examinations, additional evaluations including extracranial and transcranial arterial ultrasound examinations, transthoracic echocardiography, a 12-lead resting ECG, and continuous 24 h in-hospital blood pressure monitoring. Based on the 24 h blood pressure monitoring, the following parameters were evaluated: systolic blood pressure, diastolic blood pressure, mean blood pressure, pulse pressure, and arterial stiffness index (ASI). The modified Rankin scale (mRS) was assessed at 90 days to evaluate the 3-month clinical outcome, defining an unfavorable outcome as an mRS score ≥ 3. To assess the factors associated with unfavorable outcomes, a stepwise logistic regression model was performed on the total sample size, and the analyses were replicated after stratifying by sex. Results: A total of 334 patients (176 males, 158 females) were included in the analysis. There was a significant sex-dependent impact of ASI on the 90-day unfavorable Rankin score (mRS score ≥ 3) as only men had a reduced likelihood of favorable outcomes with increasing arterial stiffness (OR:1.54, 95% CI: 1.06-2.23; P-interaction = 0.023). Conclusions: The influence of ASI on the 3-month functional outcome after acute ischemic stroke is at least in part sex-related, suggesting that, in males, higher ASI values are associated with a worse outcome.

Ischemic stroke and diabetes: a TLR4-mediated neuroinflammatory perspective

Ischemic stroke is the major contributor to morbidity and mortality in people with diabetes mellitus. In ischemic stroke patients, neuroinflammation is now understood to be one of the main underlying mechanisms for cerebral damage and recovery delay. It has been well-established that toll-like receptor 4 (TLR4) signaling pathway plays a key role in neuroinflammation. Emerging research over the last decade has revealed that, compared to ischemic stroke without diabetes mellitus, ischemic stroke with diabetes mellitus significantly upregulates TLR4-mediated neuroinflammation, increasing the risk of cerebral and neuronal damage as well as neurofunctional recovery delay. This review aims to discuss how ischemic stroke with diabetes mellitus amplifies TLR4-mediated neuroinflammation and its consequences. Additionally covered in this review is the potential application of TLR4 antagonists in the management of diabetic ischemic stroke.

Trimethylamine-N-oxide and cerebral stroke risk: A review

Trimethylamine-N-oxide (TMAO) is a gut microbiota-derived metabolite produced by the action of gut microbiota and the hepatic enzyme Flavin Mono‑oxygenase 3 (FMO3). TMAO level has a positive correlation with the risk of cardiovascular events, including stroke, and their level is influenced mainly by dietary choice and the action of liver enzyme FMO3. TMAO plays a role in the development of atherosclerosis plaque, which is one of the causative factors of the stroke event. Preclinical and clinical investigations on the TMAO and associated stroke risk, severity, and outcomes are summarised in this review. In addition, mechanisms of TMAO-driven vascular dysfunction are also discussed, such as inflammation, oxidative stress, thrombus and foam cell formation, altered cholesterol and bile acid metabolism, etc. Post-stroke inflammatory cascades involving activation of immune cells, i.e., microglia and astrocytes, result in Blood-brain-barrier (BBB) disruption, allowing TMAO to infiltrate the brain and further aggravate inflammation. This event occurs as a result of the activation of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome pathway through the release of inflammatory cytokines and chemokines that further aggravate the BBB and initiate further recruitment of immune cells in the brain. Thus, it's likely that maintaining TMAO levels and associated gut microbiota could be a promising approach for treating and improving stroke complications.

The Value of Serial Measurement of Arterial Stiffness in Cardiovascular Disease

Clinically assessing arterial stiffness is valuable because it aids in predicting future cardiovascular events. There are several methods for measuring arterial stiffness, including pulse wave velocity (PWV), augmentation index, and pulse pressure. Numerous studies have shown that these indicators of arterial stiffness possess prognostic value for various patient groups as well as the general population. In cross-sectional studies, arterial stiffness was also linked to organ damage indices. However, most studies related to arterial stiffness have relied on a single measurement. Taking multiple serial measurements of arterial stiffness offers several advantages. Through repeated assessments, one can confirm the variability of arterial stiffness and observe changes over time, which is beneficial for understanding its pathophysiology. Such repeated measurements are also invaluable in evaluating the efficacy of interventions aimed at improving arterial stiffness. However, caution is needed, as there is no standardized method for measuring arterial stiffness. For instance, with PWV, the values can be influenced by numerous external factors. Therefore, the external conditions during the measurement must be noted. It's essential to recognize the pros and cons of repeated arterial stiffness measurements and integrate them effectively into clinical practice.

Blood pressure undulation of peripheral thrombolysis period in acute ischemic stroke is associated with prognosis

BACKGROUND

Evidence suggests that patients with higher blood pressure variability (BPV) have a higher risk for stroke but the relationship between BPV and stroke outcomes is unknown in those who underwent intravenous thrombolysis (IVT) for acute ischemic stroke (AIS). The objective of this study is to investigate the association among BPV, BP values and stroke outcomes.

METHODS

A retrospective analysis of about 510 consecutive thrombolysis cases for AIS from January 2015 to March 2019 in a single-center database were done. Then, these patients were followed-up for 3 months. We used univariate and multivariable models to evaluate the relationship between mean BP values, BPV and the risk of stroke outcomes from prior IVT to 72 h after IVT. Meanwhile, we also used COX regression to assess the hazard ratios of stroke outcomes with BPV within 3 months. Furthermore, we tested the effect of BP level at various time-points (prior to IVT and at 0, 2, 4, 8, 12, 24, 48 and 72 h after IVT) on development of postthrombolytic stroke outcomes.

RESULTS

Higher BPV from prior IVT to 72 h after IVT was associated with higher risk of stroke outcomes within 3 months [SBPV of recurrent stroke: odds ratios (OR) = 5.298, 95% confidence interval (CI) 1.339-10.968, P = 0.018; DBPV of recurrent stroke: OR = 6.397, 95% CI 1.576-25.958, P = 0.009, respectively]. In addition, patients with recurrent stroke had significantly higher mean SBP (OR=1.037, 95% CI 1.006-1.069, P = 0.019). Furthermore, higher BP at different time points were associated with greater risk of recurrent stroke from prior IVT to 72 h after IVT.

CONCLUSION

Higher BPV and SBP from prior IVT to 72 h after IVT was associated with higher risk of stroke outcomes within 3 months.

Adipocyte fatty acid-binding protein exacerbates cerebral ischaemia injury by disrupting the blood-brain barrier

Aims

Adipocyte fatty acid-binding protein (A-FABP) is an adipokine implicating in various metabolic diseases. Elevated circulating levels of A-FABP correlate positively with poor prognosis in ischaemic stroke (IS) patients. No information is available concerning the role of A-FABP in the pathogenesis of IS. Experiments were designed to determine whether or not A-FABP mediates blood–brain barrier (BBB) disruption, and if so, to explore the molecular mechanisms underlying this deleterious effects.

Methods and results

Circulating A-FABP and its cerebral expression were increased in mice after middle cerebral artery occlusion. Genetic deletion and pharmacological inhibition of A-FABP alleviated cerebral ischaemia injury with reduced infarction volume, cerebral oedema, neurological deficits, and neuronal apoptosis; BBB disruption was attenuated and accompanied by reduced degradation of tight junction proteins and induction of matrix metalloproteinases-9 (MMP-9). In patients with acute IS, elevated circulating A-FABP levels positively correlated with those of MMP-9 and cerebral infarct volume. Mechanistically, ischaemia-induced elevation of A-FABP selectively in peripheral blood monocyte-derived macrophages and cerebral resident microglia promoted MMP-9 transactivation by potentiating JNK/c-Jun signalling, enhancing degradation of tight junction proteins and BBB leakage. The detrimental effects of A-FABP were prevented by pharmacological inhibition of MMP-9.

Conclusion

A-FABP is a key mediator of cerebral ischaemia injury promoting MMP-9-mediated BBB disruption. Inhibition of A-FABP is a potential strategy to improve IS outcome.

Exosomes and Exosomal MicroRNAs in Age-Associated Stroke

Aging has been considered to be the most important non-modifiable risk factor for stroke and death. Changes in circulation factors in the systemic environment, cellular senescence and artery hypertension during human ageing have been investigated. Exosomes are nanosize membrane vesicles that can regulate target cell functions via delivering their carried bioactive molecules (e.g. protein, mRNA, and microRNAs). In the central nervous system, exosomes and exosomal microRNAs play a critical role in regulating neurovascular function, and are implicated in the initiation and progression of stroke. MicroRNAs are small non-coding RNAs that have been reported to play critical roles in various biological processes. Recently, evidence has shown that microRNAs are packaged into exosomes and can be secreted into the systemic and tissue environment. Circulating microRNAs participate in cellular senescence and contribute to age-associated stroke. Here, we provide an overview of current knowledge on exosomes and their carried microRNAs in the regulation of cellular and organismal ageing processes, demonstrating the potential role of exosomes and their carried microRNAs in age-associated stroke.

Blood Pressure Management in Acute Ischemic Stroke

PURPOSE OF REVIEW

Abrupt blood pressure (BP) rise is the most common clinical symptom of acute ischemic stroke (AIS). However, BP alterations during AIS reflect many diverse mechanisms, both stroke-related and nonspecific epiphenomena, which change over time and across patients. While extremes of BP as well as high BP variability have been related with worse outcomes in observational studies, optimal BP management after AIS remains challenging.

RECENT FINDINGS

This review discusses the complexity of the factors linking BP changes to the clinical outcomes of patients with AIS, depending on the treatment strategy and local vessel status and, in particular, the degree of reperfusion achieved. The evidence for possible additional clinical markers, including the presence of arterial hypertension, and comorbid organ dysfunction in individuals with AIS, as informative and helpful factors in therapeutic decision-making concerning BP will be reviewed, as well as recent data on neurovascular monitoring targeting person-specific local cerebral perfusion and metabolic demand, instead of the global traditional parameters (BP among others) alone. The individualization of BP management protocols based on a complex evaluation of the homeostatic response to focal cerebral ischemia, including but not limited to BP changes, may be a valuable novel goal proposed in AIS, but further trials are warranted.

Decrease in Pulse Wave Velocity is Associated with Clinical Improvement in Patients with Ischemic Stroke

BACKGROUND

Arterial stiffness is an independent determinant of cardiovascular and cerebrovascular risks. The relationship between the increase in arterial stiffness parameters and the severity of stroke has been shown in previous studies. We aimed to investigate the association between clinical improvement and changes in arterial stiffness parameters in patients presenting acute ischemic stroke.

METHODS

A total of 107 patients were enrolled in this study. On the first and seventh day of the hospitalization, 24 h non-invasive blood pressure was monitored and arterial stiffness parameters were measured. The National Institutes of Health Stroke Scale (NIHSS) was used to determine the severity of stroke, and the Modified Rankin Scale was used to determine dependency and to evaluate functional improvements.

RESULTS

Arterial stiffness parameters of augmentation index (AIx@75) and pulse wave velocity (PWV) were significantly higher in patients who died during hospitalization than patients who were discharged (respectively p <0.001, p = 0.04). In the group with clinical improvement, PWV values measured on the seventh day were significantly lower than PWV values measured on the first day (p = 0.032). When the changes in PWV value measured on the first and seventh day for both groups were analyzed using mixed ANOVA test, p value were significant (p = 0.033). Multivariate binary logistic regression analyses showed that negatively change in PWV and CDBP independently predicts the clinical improvement.

CONCLUSIONS

Increased AIx@75 and PWV appear to be associated with higher in-hospital mortality rates in patients with acute ischemic stroke. Additionally, clinical improvement in patients with ischemic stroke is associated with a decrease in PWV .

Brachial-Ankle Pulse Wave Velocity Versus Its Stiffness Index β-Transformed Value as Risk Marker for Cardiovascular Disease

Background

The difference in the predictive ability of the brachial‐ankle pulse wave velocity (baPWV) and its stiffness index β‐transformed value (β‐baPWV, ie, baPWV adjusted for the pulse pressure) for the development of pathophysiological abnormalities related to cardiovascular disease or future occurrence of cardiovascular disease was examined.

Methods and Results

In study 1, a 7‐year prospective observational study in cohorts of 3274 men and 3490 men, the area under the curve in the receiver operator characteristic curve analysis was higher for baPWV than for β‐baPWV for predicting the development of hypertension (0.73, 95% CI=0.70 to 0.75 versus 0.59, 95% CI=0.56 to 0.62; P<0.01) and/or the development of retinopathy (0.78, 95% CI=0.73 to 0.82 versus 0.66, 95% CI=0.60 to 0.71; P<0.01) by the end of the study period. During study 2, a 3‐year observation period on 511 patients with coronary artery disease, 72 cardiovascular events were confirmed. The C statistics of both markers for predicting the development of cardiovascular events were similar.

Conclusions

Stiffness index β transformation of the baPWV may attenuate the significance of the baPWV as a risk marker for development of pathophysiological abnormalities related to cardiovascular disease in male subjects.

Distinct proteomic profiles in monozygotic twins discordant for ischaemic stroke

Stroke is a common disorder with significant morbidity and mortality, and complex aetiology involving both environmental and genetic risk factors. Although some of the major risk factors for stoke, such as smoking and hypertension, are well-documented, the underlying genetic and detailed molecular mechanisms remain elusive. Exploring the relevant biochemical pathways may contribute to the clinical diagnosis of stroke and shed light on its aetiology. A comparative proteomic analysis of blood serum of a pair of monozygotic (MZ) twins discordant for ischaemic stroke (IS) was performed using a label-free quantitative proteomics approach. To overcome the limit of reproducibility in the serum preparation, two separate runs were performed, each consisting of three technical replicates per sample. Biological processes associated with proteins differentially expressed between the twins were explored with gene ontology (GO) classification using the functional analysis tool g:Profiler. ANOVA test performed in Progenesis LC-MS identified 179 (run 1) and 209 (run 2) proteins as differentially expressed between the affected and unaffected twin (p < 0.05). Furthermore, the level of serum fibulin 1, an extracellular matrix protein associated with arterial stiffness, was on average 13.37-fold higher in the affected twin. Each dataset was then analysed independently, and the proteins were classified according to GO terms. The categories overrepresented in the affected twin predominantly corresponded to stroke-relevant processes, including wound healing, blood coagulation and haemostasis, with a high proportion of the proteins overexpressed in the affected twin associated with these terms. By contrast, in the unaffected twin diagnosed with atopic dermatitis, there were increased levels of keratin proteins and GO terms associated with skin development. The identification of cellular pathways enriched in IS as well as the upregulation of fibulin 1 sheds new light on the underlying disease-causing mechanisms at the molecular level. Our findings of distinct proteomic signatures associated with IS and atopic dermatitis suggest proteomic profiling could be used as a general approach for improved diagnostic, prognostic and therapeutic strategies.

Plasma Klotho concentrations predict functional outcome at three months after acute ischemic stroke patients

Background: The Klotho protects the cardiovascular system by protecting against cell apoptosis, inhibiting the production of reactive oxygen species, and modulating inflammation. We aimed to investigate relationship of plasma Klotho concentrations with functional outcome at 3 months after acute cerebral infarction. Methods: We prospectively enrolled 262 first-ever acute cerebral infarction patients from whom a blood sample was acquired within 24 h of admission. An enzyme-linked immunosorbent assay was used for evaluating plasma Klotho concentration. Functional outcome on admission and three months was evaluated. Results: Of the 262 patients, 152 (58.0%) were men. The mean age of these patients was 64.7 years. The mean ± standard deviation of plasma Klotho concentrations was 312.7 ± 153.3 pg/mL. As opposed to patients with good outcome, plasma Klotho levels were lower in the poor outcome group (207.8 ± 96.2 vs. 342.5 ± 153.5 pg/mL, p = .001). In multivariate analysis, increased plasma Klotho concentrations were independently associated with good functional outcome (Odds ratio: 2.42, 95% confidence interval: 1.45-4.04, p < .001). Conclusions: Increased plasma Klotho concentrations were associated with good functional outcome in patients with acute ischemic stroke. We attribute these associations to the pleiotropic effects of Klotho in stroke and vascular diseases. Key message Increased plasma Klotho concentrations were associated with good functional outcome in patients with acute ischemic stroke.

Cerebral Haemodynamics: Effects of Systemic Arterial Pulsatile Function and Hypertension

PURPOSE OF REVIEW

Concepts of pulsatile arterial haemodynamics, including relationships between oscillatory blood pressure and flow in systemic arteries, arterial stiffness and wave propagation phenomena have provided basic understanding of underlying haemodynamic mechanisms associated with elevated arterial blood pressure as a major factor of cardiovascular risk, particularly the deleterious effects of isolated systolic hypertension in the elderly. This topical review assesses the effects of pulsatility of blood pressure and flow in the systemic arteries on the brain. The review builds on the emerging notion of the "pulsating brain", taking into account the high throughput of blood flow in the cerebral circulation in the presence of mechanisms involved in ensuring efficient and regulated cerebral perfusion.

RECENT FINDINGS

Recent studies have provided evidence of the relevance of pulsatility and hypertension in the following areas: (i) pressure and flow pulsatility and regulation of cerebral blood flow, (ii) cerebral and systemic haemodynamics, hypertension and brain pathologies (cognitive impairment, dementia, Alzheimer's disease), (iii) stroke and cerebral small vessel disease, (iv) cerebral haemodynamics and noninvasive estimation of cerebral vascular impedance, (v) cerebral and systemic pulsatile haemodynamics and intracranial pressure, (iv) response of brain endothelial cells to cyclic mechanical stretch and increase in amyloid burden. Studies to date, producing increasing epidemiological, clinical and experimental evidence, suggest a potentially significant role of systemic haemodynamic pulsatility on structure and function of the brain.

Arterial stiffness and stroke: de-stiffening strategy, a therapeutic target for stroke

Stroke is the second leading cause of mortality and morbidity worldwide. Early intervention is of great importance in reducing disease burden. Since the conventional risk factors cannot fully account for the pathogenesis of stroke, it is extremely important to detect useful biomarkers of the vascular disorder for appropriate intervention. Arterial stiffness, a newly recognised reliable feature of arterial structure and function, is demonstrated to be associated with stroke onset and serve as an independent predictor of stroke incidence and poststroke functional outcomes. In this review article, different measurements of arterial stiffness, especially pressure wave velocity, were discussed. We explained the association between arterial stiffness and stroke occurrence by discussing the secondary haemodynamic changes. We reviewed clinical data that support the prediction role of arterial stiffness on stroke. Despite the lack of long-term randomised double-blind controlled therapeutic trials, it is high potential to reduce stroke prevalence through a significant reduction of arterial stiffness (which is called de-stiffening therapy). Pharmacological interventions or lifestyle modification that can influence blood pressure, arterial function or structure in either the short or long term are promising de-stiffening therapies. Here, we summarised different de-stiffening strategies including antihypertension drugs, antihyperlipidaemic agents, chemicals that target arterial remodelling and exercise training. Large and well-designed clinical trials on de-stiffening strategy are needed to testify the prevention effect for stroke. Novel techniques such as modern microscopic imaging and reliable animal models would facilitate the mechanistic analyses in pathophysiology, pharmacology and therapeutics.

Prognostic Impact of Cerebral Small Vessel Disease on Stroke Outcome

Cerebral small vessel disease (SVD), which includes white matter hyperintensities (WMHs), silent brain infarction (SBI), and cerebral microbleeds (CMBs), develops in a conjunction of cumulated injuries to cerebral microvascular beds, increased permeability of blood-brain barriers, and chronic oligemia. SVD is easily detected by routine neuroimaging modalities such as brain computed tomography or magnetic resonance imaging. Research has revealed that the presence of SVD markers may increase the risk of future vascular events as well as deteriorate functional recovery and neurocognitive trajectories after stroke, and such an association could also be applied to hemorrhagic stroke survivors. Currently, the specific mechanistic processes leading to the development and manifestation of SVD risk factors are unknown, and further studies with novel methodological tools are warranted. In this review, recent studies regarding the prognostic impact of WMHs, SBI, and CMBs on stroke survivors and briefly summarize the pathophysiological concepts underlying the manifestation of cerebral SVD.

Plasma soluble vascular adhesion protein-1 concentration correlates with arterial stiffness: A cross-sectional study

BACKGROUND

Arterial stiffness is related to inflammation, oxidative stress, advanced glycation end products (AGEs), and endothelial dysfunction. Vascular adhesion protein-1 (VAP-1) is both as an adhesion molecule involving in inflammation and as an amine oxidase producing aldehyde and hydrogen peroxide involved in protein cross-linking, oxidative stress and endothelial injury.

OBJECTIVE

We explored the associations of plasma soluble VAP-1 (sVAP-1) with arterial stiffness.

DESIGN

Cross-sectional study.

SETTING

Health Examination Center at the General Hospital of the Air Force in Beijing, China.

SUBJECTS

568 Han Chinese healthy persons living in Beijing (aged 50.7 ± 8.0 years).

METHODS

sVAP-1 concentration was assessed by enzyme-linked immunosorbent assay. Arterial stiffness was measured as brachial-ankle pulse wave velocity (baPWV) on both left and right sides of the examinees, and the larger and the mean values were recorded. Cardiovascular risk factors were investigated.

RESULTS

sVAP-1 was significantly associated with maximal or mean baPWV in subjects of age ≥ 60 years after adjusting for baPWV-related confounders (β=36.922, p<0.05 or β=32.512, p<0.05) or after adjusting for all the variables (β=37.924, p<0.05 or β=33.193, p<0.05), but not in subjects of age <60 years. sVAP-1 had an independent and positive correlation with age (r=0.222, p<0.001).

CONCLUSIONS

Plasma sVAP-1, increased with age, is associated with arterial stiffness in older individuals. VAP-1 may be important mechanism for vascular aging.