Cerebral Autoregulation in Patients With Symptomatic Cerebral Atherosclerotic Stenosis

Study Overview
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Brief Summary
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In this multi-center prospective observational study within a cohort of symptomatic cerebral atherosclerotic stenosis (sCAS) patients, 850 subjects were planed to be enrolled to explore the relationship between cerebral autoregulation (CA) and stroke recurrence, determine the threshold values of CA parameter for predicting stroke recurrence associated with particular stenosis.

Detailed Description
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Ischemic stroke is a tremendous public health burden that seriously endangers the health of Chinese population symptomatic cerebral atherosclerotic stenosis (sCAS) is responsible for about 33-50% of ischemic stroke in China and highly associated with the risk of stroke recurrence. Cerebral autoregulation (CA) is the main protective mechanism that modulates cerebral blood flow to satisfy regional cerebral perfusion demands despite of variations in arterial blood pressure (ABP). Thus, CA supposed to be particularly considered when choosing individual therapeutic strategy in sCAS patients. In clinical practice, applying transcranial Doppler combined with servo-controlled plethysmograph assessing CA has been proved a feasible method in cerebral atherosclerotic stenosis patients. Especially in those severe stenosis patients, CA is probably compromised in varying degrees, whereas whether and to what extent CA parameters have the capability to predict stroke recurrence has not been illustrated. Thus, the aim of the study was to assess CA after acute ischemic stroke or transient ischemic attack within 2 years follow-up to explore the relationship between CA and stroke recurrence and determine the threshold values of CA parameter to predict stroke recurrence. CA measurement will be performed at 0-3 and 10-30 days after ischemic cerebrovascular events. Clinical information, neuroimaging data, biochemical examinations and follow-up information will be collected and recorded in case report form (CRF) once signing of informed consent.

Official Title
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Cerebral Autoregulation in Patients With Symptomatic Cerebral Atherosclerotic Stenosis

Conditions
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Cerebrovascular Stroke, Cerebral Artery Stenosis

Intervention / Treatment
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* Diagnostic Test: Cerebral autoregulation assessment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ranging from 18 to 80, both genders Unilateral internal carotid artery (ICA) or M1 segment of middle cerebral artery (MCA) stenosis (rate of stenosis ranging from 50-99%) Acute ischemic cerebrovascular events (TIA or ischemic stroke) within cerebral stenotic artery supplying area Onset of disease <30 d before enrollment Modified Ranking Scale (mRS) ≤1 before stroke onset National Institutes of Health Stroke Scale (NIHSS) ≤20 Sufficient bilateral temporal bone windows for insonation of the middle cerebral artery Be conscious, and able to cooperate with CA assessment Willing to participate and sign the informed consent Exclusion Criteria: Vertebral artery (VA), basilar artery (BA), anterior cerebral artery (ACA), or posterior cerebral artery (PCA) stenosis; Bilateral internal carotid artery (ICA) or M1 segment of middle cerebral artery (MCA) stenosis(rate of stenosis ranging from 50-99%) Patients who have received or plan to undergo intravascular interventional treatment/endarterectomy Other intracranial diseases, including cerebral hemorrhage (primary or secondary), intracranial neoplasm, aneurysm, arteriovenous malformation, etc. Evidence for embolic stroke, such as atrial fibrillation, prosthetic valve surgery, and suspected endocarditis, etc. Arrhythmia, anemia and hyperthyroidism which may influence the stability of cerebral blood flow diagnosed by two physicians by electrocardiogram and laboratory tests. Dementia, severe anxiety, depression, and other mental diseases Malignant neoplasm and expected lifetime <2 years Enrolled in other clinical trails within 6 months

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| sCAS patients<br>Investigators plan to enroll 850 patients of symptomatic cerebral atherosclerotic stenosis (sCAS) for cerebral autoregulation assessment to explore the relationship between cerebral autoregulation (CA) and stroke recurrence, determine the threshold values of CA parameter for predicting stroke recurrence associated with particular stenosis. | Diagnostic Test: Cerebral autoregulation assessment<br>* Cerebral autoregulation assessment will be conducted by specialized neurovascular ultrasound doctors during 0-3 and 10-30 days after stroke onset.The recorded data will be stored for further cerebral autoregulation analysis.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Stroke recurrence rate | Ischemic cerebrovascular recurrence (TIA or ischemic stroke) within cerebral stenotic artery supplying area diagnosed by symptoms and imaging examinations. | two years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The index of cerebral autoregulation | Phase difference, gain and coherence of symptomatic cerebral atherosclerotic stenosis patients within 30 days ischemic cerebrovascular events onset. | within 30 days ischemic cerebrovascular events onset | 
| ischemic cerebrovascular recurrence rate | All ischemic cerebrovascular recurrence (TIA or ischemic stroke) within two years follow-up diagnosed by symptoms and imaging examinations. | two years | 
| The first onset time of composite endpoint events within 2 years | The composite endpoint events include fatal and nonfatal stroke (ischemic or hemorrhagic stroke), fatal and nonfatal myocardial infarction, transient ischemic attack (TIA) diagnosed by symptoms and imaging examinations. | two years follow-up | 
| mRS and Barthel score | The changes of mRS and Barthel score within 2 years | two years | 
| The first onset time of each individual part of composite endpoint events within 2 years | The first onset time of each individual part of composite endpoint events within 2 years | two years follow-up | 
| the NIHSS score | The changes of NIHSS score from admission to discharge | within 1 month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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cerebral atherosclerotic stenosis, ischemic stroke, transient ischemic attack, cerebral autoregulation