scholarly journals Physiologically Based Model of Acute Ischemic Stroke

2002 ◽  
Vol 22 (8) ◽  
pp. 1010-1018 ◽  
Author(s):  
Vincent Duval ◽  
Sylvie Chabaud ◽  
Pascal Girard ◽  
Michel Cucherat ◽  
Marc Hommel ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Cerebral Metabolism ◽  
Internal Validity ◽  
Metabolism Rate ◽  
Positron Emission ◽  
Apparent Diffusion ◽  
Mathematical Equations ◽  
Definition Of ◽  
Key Steps

In the treatment of acute ischemic stroke most of the clinical trials have failed, contrasting with promising results in the preclinical stages. This continuing discrepancy suggests some misconceptions in the understanding of acute ischemic stroke. One possible method for identifying the shortcomings of present-day approaches is to integrate all the available knowledge into a single mathematical model and to subject that model to challenges via simulations with available experimental data. As a first stage, then, the authors developed a simplified model, defining the structure and the different parameters that represent the phenomena that occur during the hyperacute phase of ischemic stroke. First, the different critical points of the evolution of ischemic stroke, based on the available evidence on the pathophysiology of stroke, were identified. Those key steps were then related to the quantitative data obtained by magnetic resonance imaging and positron emission tomography scan. These two techniques allow the measurement of diverse key markers of cerebral metabolism: cerebral blood flow (CBF), oxygen extraction factor, cerebral metabolism rate of oxygen, and the apparent diffusion coefficient of water, among others. Those markers were organized together through mathematical equations, and changed over time in order to describe the evolution of an acute ischemic stroke. At each time during the evolution of stroke those parameters are summarized in a parameter called survival delay. This parameter made possible the definition of three different states for tissues—functional, infarcted, salvageable—as end point. Once the model was designed, simulations were performed to explore its internal validity. Simulation results were consistent with the reality of acute ischemic stroke and did not reveal any major drawbacks in the use of the model. The more rapid the decrease in CBF, the larger is the final infarcted area. The model also allowed for the characterization of two types of tissue in the penumbra: tissues with an initial metabolic impairment and tissues altered owing to the closeness of the ischemic area. The results of this experiment were consistent with what is known of acute ischemic stroke. The model integrated different markers of acute ischemic stroke into a single entity in order to mimic acute ischemic stroke, and has been shown to have a reasonable degree of internal validity.

Association of SLCO1B1 and ABCB1 Genetic Variants with Atorvastatin-induced Myopathy in Patients with Acute Ischemic Stroke

2019 ◽  
Vol 25 (14) ◽  
pp. 1663-1670 ◽  
Author(s):  
Limin Zhang ◽  
Hong Lv ◽  
Qian Zhang ◽  
Dongzhi Wang ◽  
Xixiong Kang ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Genetic Variants ◽  
Reference Laboratory ◽  
Nucleotide Polymorphisms ◽  
Significant Difference ◽  
Definition Of ◽  
Patients Experience ◽  
And Control ◽  
Mutant Frequency

Background:Certain patients experience muscle-related adverse effects after taking atorvastatin. Genetic factors play an important role in the occurrence of statin-induced myopathy.Aim:We aimed to identify genetic variants associated with statin-induced myotoxicity.Methods:We prospectively enrolled 1,102 acute ischemic stroke patients who underwent atorvastatin treatment for the first time after admission. Patients were separated into case and control groups after a follow-up of 3 months. We used a biochemical definition of myopathy consisting of serum creatine kinase values more than ten times the upper limit of normal for the reference laboratory (150 U/L). Fifty single nucleotide polymorphisms (SNPs) from seven genes of ABCB1, CoQ2, HTR3B, RYR2, CYP3A5, HTR7 and SLCO1B1 were selected and genotyped. The effects of genetic polymorphisms on myopathy were observed.Results:61 cases and 110 controls were recruited in the study. Compared with the controls, the cases had a significant higher mutant frequency of the allele A (ABCB1, rs2373588) (OR = 2.01, 95%CI = 1.10-3.67, P = 0.001) and a significant lower mutant frequency of the allele A (SLCO1B1, rs976754) (OR = 1.85, 95%CI = 1.12-3.03, P = 0.042). Genotypes or alleles of the other SNPs had no significant difference between the two groups (P > 0.05).Conclusion:Our findings reveal that SLCO1B1 and ABCB1 genetic variants are associated with statin-induced myopathy. These are valuable biomarkers for the evaluation of atorvastatin safety.

Defining Minor Symptoms in Acute Ischemic Stroke

2015 ◽  
Vol 39 (3-4) ◽  
pp. 209-215 ◽  
Author(s):  
Davide Strambo ◽  
Alberto A. Zambon ◽  
Luisa Roveri ◽  
Giacomo Giacalone ◽  
Giovanni Di Maggio ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Motor Impairment ◽  
Epidemiological Data ◽  
Minor Stroke ◽  
Predictors Of Outcome ◽  
Stroke Patients ◽  
Nihss Score ◽  
Poor Outcome ◽  
Definition Of

Background: Thrombolysis is often withheld from acute ischemic stroke patients presenting with mild symptoms; however, up to 40% of these patients end up with a poor outcome when left untreated. Since there is lack of consensus on the definition of minor symptoms, we aimed at addressing this issue by looking for features that would better predict functional outcomes at 3 months. Methods: Among all acute ischemic stroke patients admitted to our Stroke Unit (n = 1,229), we selected a cohort of patients who arrived within 24 hours from symptoms onset, with baseline NIHSS ≤6, not treated with thrombolysis (n = 304). Epidemiological data, comorbidities, radiological features and clinical presentation (NIHSS items) were collected to identify predictors of outcome. Our cohort was tested against minor stroke definitions selected from the literature and a newly proposed one. Results: Three months after stroke onset, 97 patients (31.9%) had mRS ≥2. Independent predictors of poor outcome were age (OR 0.97 [95% CI 0.95-9.99]) and baseline NIHSS score (OR 0.79 [95% CI 0.67-0.94]), while cardioembolic aetiology was negatively associated (OR 3.29 [95% CI 1.51-7.14]). Items of NIHSS associated with poor outcome were impairment of right motor arm (OR 0.49 [95% CI 0.27-0.91]) or the involvement of any of the motor items (OR 0.69 [95% CI 0.48-0.99]). The definition of minor stroke as NIHSS ≤3 and the new proposed definition had the highest sensitivity and accuracy and were independent predictors of outcome. Conclusions: Our study confirmed that in spite of a low NIHSS score, one third of patients had poor outcome. As already described, age and NIHSS score remained independent predictors of poor outcome even in mild stroke. Also, motor impairment appeared a major determinant of poor outcome. The new proposed definition of minor stroke featured the NIHSS score and the NIHSS items that better predicted functional outcome. Awareness that even minor stroke can yield to poor outcome should sensitize patients to arrive early to the ED and neurologists to administer rt-PA.

Abstract WP60: Evaluation of Tissue Reversibility by Relative Apparent Diffusion Coefficient Value in Acute Ischemic Stroke Patients Treated With Successful Thrombectomy

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Toshihiro Ueda ◽  
Tatsuro Takada ◽  
Shinji Nogoshi ◽  
Satoshi Takaishi ◽  
Tomohide Yoshie ◽  
...  
Keyword(s):  
Diffusion Coefficient ◽  
Ischemic Stroke ◽  
Apparent Diffusion Coefficient ◽  
Acute Ischemic Stroke ◽  
Stroke Patients ◽  
Infarcted Area ◽  
Apparent Diffusion Coefficient Value ◽  
Apparent Diffusion ◽  
The Mean ◽  
The Relationship

Background: By recent advance of endovascular thrombectomy, we have often experienced acute ischemic patients who have diffusion weighted imaging (DWI) reversal lesions after earlier successful recanalization. We retrospectively investigated the relationship between apparent diffusion coefficient (ADC) thresholds of tissue infarction and time from onset to recanalization in acute ischemic stroke patients. Methods: We assessed 24 patients who have occlusion of internal carotid artery (n=11) and the main trunk of middle cerebral artery (n=13) and obtained recanalization of TICI2b (n=12) and TICI3 (n=12) by thrombectomy and performed MRI before and after treatment. Relative ADC (rADC) value were calculated for initial DWI lesions and around hypoperfused regions. We evaluated rADC values in infarcted and non-infarcted area and analyzed the relationship between rADC thresholds of tissue infarction and time. Results: The mean time from onset to recanalization was 209 minutes and mean initial NIHSS was 15.4. The mean rADC value was 0.633 in infarcted lesions and 0.905 in non-infarcted area (p<0.001). The thresholds for rADC value for infarction by the area under the curve derived from receiver operating characteristic curve analysis were 0.769 in the area which recanalized under 180 minutes form the onset, 0.792 in that from 180 to 240 minutes, and 0.798 in that over 240 minutes. Conclusion: The estimation of rADC value may be useful in predicting the likelihood of DWI lesion reversal. Marked decreasing of rADC value which is under thresholds of infarction indicated irreversible damage of ischemic tissue regardless of early successful recanalization.

scholarly journals Correlation of Apparent Diffusion Coefficient and Computed Tomography Density in Acute Ischemic Stroke

Stroke ◽  
2002 ◽  
Vol 33 (7) ◽  
pp. 1786-1791 ◽  
Author(s):  
Thomas Kucinski ◽  
Ole Väterlein ◽  
Volkmar Glauche ◽  
Jens Fiehler ◽  
Ernst Klotz ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Diffusion Coefficient ◽  
Ischemic Stroke ◽  
Apparent Diffusion Coefficient ◽  
Acute Ischemic Stroke ◽  
Apparent Diffusion

scholarly journals Elevated ESRS, serum FIB, Hcy and stroke history were independent risk factors to PAIS

Pteridines ◽  
2018 ◽  
Vol 29 (1) ◽  
pp. 165-171
Author(s):  
Tao Zhang ◽  
Huiyun Li ◽  
Ling Li ◽  
Faying Zhou
Keyword(s):  
Risk Factors ◽  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Pearson Correlation ◽  
Statistical Significance ◽  
Pearson Correlation Test ◽  
Independent Risk Factors ◽  
Definition Of ◽  
Sensitivity Specificity ◽  
Medical University

Abstract Background: The aim of this study was to investigate the diagnostic performance of serum homocysteine (Hcy) and Essen stroke risk score (ESRS) in prediction of progressing acute ischemic stroke (PAIS).Methods One hundred and thirty two acute ischemic stroke (AIS) patients were retrospectively recruited from Daping Hospital, Third Military Medical University from February 2016 to January 2018. The 132 AIS patients were divided into PAIS and non-progressing AIS (NPAIS) groups according to the definition of PAIS. The clinical characteristics, serum Hcy concentration, and ESRS were compared between the PAIS and NPAIS groups. The independent risk factors for PAIS were evaluated by logistic regression analysis. The prediction sensitivity, specificity and area under the ROC curve (AUC) of serum Hcy and ESRS for PAIS were calculated using STATA11.0 software.Results: The elevated ESRS (OR=1.82, p<0.05), serum fibrinogen (FIB) (OR=1.18, p<0.05), Hcy (OR=1.21, p<0.05) and personal stroke history (OR=1.74, p<0.05) were independent risk factors for PAIS. The serum Hcy of the PAIS and NPAIS groups were 24.59±9.24 (μmol/L) and 18.20±8.29 (μmol/L) respectively with a statistical significance of p<0.05. The ESRS were 3.43±1.09 and 2.60±0.92 for the PAIS and NPAIS groups respectively, with a significance of p<0.05. The prediction sensitivity, specificity and AUC were 76.24%, 67.74% and 0.73 (95%CI:0.63-0.83), respectively, for serum Hcy. For ESRS, the prediction sensitivity, specificity and AUC were 69.99%, 64.52% and 0.74 (95%CI:0.63-0.84) respectively. Correlation between serum Hcy and ESRS was evaluated by a Pearson correlation test. Significant positive correlation between serum Hcy and ESRS was found in PAIS (r=0.54, p<0.05), and NPAIS patients (r=0.78, p<0.01).Conclusion: Patients with elevated ESRS, serum FIB, Hcy and stroke history had an elevated risk of developing PAIS.

Time to Reset the Definition of Successful Revascularization in Endovascular Treatment of Acute Ischemic Stroke

2018 ◽  
Vol 46 (1-2) ◽  
pp. 40-45 ◽  
Author(s):  
Andreia Carvalho ◽  
Mariana Rocha ◽  
Marta Rodrigues ◽  
Tiago Gregório ◽  
Henrique Costa ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Endovascular Treatment ◽  
Acute Ischemic Stroke ◽  
Functional Independence ◽  
Anterior Circulation ◽  
Vessel Occlusion ◽  
Study Population ◽  
Large Heterogeneity ◽  
Definition Of ◽  
Better Than

Background: A 2013 consensus statement recommended the use of the modified Treatment In Cerebral Ischemia (mTICI) scale to evaluate angiographic revascularization after endovascular treatment (EVT) of acute ischemic stroke due to its higher inter-rater agreement and capacity of clinical outcome prediction. The current definition of successful revascularization includes the achievement of grades mTICI 2b or 3. However, mTICI 2b grade encompasses a large heterogeneity of revascularization states, and prior studies suggested that the magnitude of benefit derived from mTICI 2b and mTICI 3 does not seem to be equivalent. In a way to restrain the referred heterogeneity, Goyal et al. [J Neurointerv Surg 2014; 6: 83–86] proposed a revised mTICI scale that includes a 2c grade (rTICI). Methods: Retrospective analysis of prospectively collected data from consecutive cases of EVT for anterior circulation large-vessel occlusion, performed between January 2015 and July 2017. Patients with mTICI 2b or 3 grades were reclassified according to the rTICI scale, and the outcomes between the 3 revascularization grades (rTICI 2b, 2c, 3) compared. Results: Our study population of 226 patients (64 rTICI 2b, 30 rTICI 2c, 132 rTICI 3) has a mean age of 71 years, 48.2% males, median baseline NIHSS of 16 (13–19) and ASPECTS of 8 (7–9). The 3 revascularization grades are represented by homogeneous populations. Logistic regression analysis showed statistically significant higher rates of functional independence at 3 months (65.9 vs. 50.0%; adjusted OR 0.39, 95% CI 0.18–0.86), with lower rates of mortality (8.3 vs. 15.6%; adjusted OR 3.54, 95% CI 1.14–10.97) and intracranial hemorrhage (ICH) in rTICI 3 than 2b groups. When comparing rTICI 3 with 2c groups, there were only statistically significant differences in the total ICH rate (8.3 vs. 26.7%; adjusted OR 7.08, 95% CI 1.80–27.82) but not in symptomatic ICH. Conclusions: These results corroborate the scarce prior findings suggesting that patients with rTICI 2c grade should be reported separately, since they have similar outcomes to rTICI 3, and better than rTICI 2b patients. Therefore, we suggest resetting the angiographic revascularization endpoint to perfect revascularization (rTICI 2c or 3 grades), a target that neurointerventionalists should strive to achieve.

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