Active clinical trials for "Ischemic Stroke"

Stroke is the first and the fourth leading cause of death in the United States and China, respectively. Disruption of cerebrovascular vulnerable atherosclerotic plaque is the major etiology of ischemic stroke. Therefore, early detection and treatment of vulnerable plaques occurring at the feeding arteries to brain (cerebral arteries) will be helpful for prevention of stroke. Atherosclerosis is a systemic disease that usually affects multiple vascular beds. Previous studies have shown that these high risk lesions in different segments of cerebral arteries (intracranial and extracranial arteries) might be racially specific. It is reported that, in stroke patients, intracranial vulnerable plaques are prevalent in Asian populations whereas atherosclerosis more frequently involves extracranial carotid arteries in American subjects. However, these findings are based on angiographic imaging approaches via measuring arterial luminal stenosis. Because the atherosclerotic plaque often appears as outward expansion, namely positive remodeling during progression, measuring luminal stenosis will underestimate the disease severity. Hence, directly viewing the plaque in the vessel wall is strongly suggested in order to objectively evaluate the cerebrovascular vulnerable plaque. High resolution, black-blood magnetic resonance (MR) imaging has been widely used to accurately characterize carotid vulnerable plaque in the last two decades. The aim of using MR black-blood techniques is to suppress the blood signal (black) to enhance the signal contrast between the vessel wall and blood in the arterial lumen. Excellent agreement has been achieved between MR imaging and histology in identification of plaque components, such as intraplaque hemorrhage and lipid core. For assessing carotid plaque, MR imaging is superior to computed tomography and ultrasound imaging techniques due to its advantages including noninvasive imaging, lack of ionizing radiation, excellent soft tissue resolution, and multi-parametric image acquisition. The Investigators hypothesize that there are specific characteristics in carotid vulnerable plaques in Chinese patients with ischemic cerebrovascular events such as ischemic stroke and transient ischemic attack (TIA). This study seeks to investigate the characteristics of vulnerable plaque in carotid arteries using high resolution, black-blood MR imaging in patients with recent TIA or ischemic stroke. This is a cross-sectional, multicenter study. A total of 1000 patients will be recruited from more than 10 different hospitals across China within 3 years. All patients will undergo MR imaging for brain and carotid arteries within two weeks after symptom onset. The prevalence of carotid vulnerable plaque and its correlations with brain ischemic lesions, traditional risk factors, and regional distribution of China will be determined.

The cerebrovascular diseases can be approximately divided as two types, namely ischemic and hemorrhagic stroke. Intravenous thrombolysis within 3-4.5 hours is highly recommended for acute ischemic stroke patients. But it's difficult to diagnose the ischemic stroke with the hemorrhagic stroke from the early symptoms and signs. It's with high risk of enlarging the hematoma if the patients with hemorrhagic stroke received the thrombolytic drugs. And time cost by CT or MRI examination is likely to responsible for missing the narrow time window and poor prognosis of stroke patients. Consequently, seeking for a noninvasive, rapid, portable and inexpensive diagnosis method which can sensitively distinguish the stroke type before CT or MRI examination would be very helpful in treating the ischemic stroke patients. Because of the blockage in the cerebral supply artery, the heat from circulatory system will sharply decrease in infracted hemisphere among the ischemic stroke patients. The reduced brain temperature influenced the temperature on the ipsilateral forehead according to the data of our animal and preliminary clinical trial. In contrast, the temperature of the ipsilateral hemisphere showed a mild increase among the ischemic stroke patients in our preliminary experiment. The difference of the temperature tendency on the ipsilateral forehead has a great chance to be an early physical mark. In our study, 30 ischemic stroke patients and 30 hemorrhagic stroke patients will be recruited. In the process of recruitment, the patients with acute stroke attack in no more than 4.5 hours will be collected the temperature at the five point without head coverage, including ipsilateral tempora, ipsilateral forehead, galbella, contralateral forehead, and contralateral tempora. Then the stroke would be recruited into the ischemic and hemorrhagic group according to the later CT or MRI results in the hospital. The accuracy and sensibility of early brain temperature in distinguishing stroke type would be tested in comparison with the diagnosis of imaging examination.

This is a new vessel wall imaging-based stroke registry which will investigate the clinical utility of the whole-brain intracranial vessel wall Magnetic Resonance Imaging (MRI) technique in assessing the etiologies in patients with ischemic stroke.

A prospective, multicenter, cohort study to explore the stroke mechanisms of symptomatic intracranial atherosclerosis, the dynamic changes under aggressive medical treatment and their associations with clinical events using conventional MRI sequences plus high-resolution magnetic resonance (HR-MRI).

Title: Conduct of anaesthesia during acute ischaemic stroke: a retrospective case series of patients undergoing mechanical thrombectomy. Design: This study will be a retrospective consecutive observational case series

Previous research has shown there wasn't inevitable relationship between mismatch area and infarct growth according to Volumetric-subtraction mismatch volume.The recently published on Stroke paper has proposed Coregistration mismatch to calculate the mismatch to replace ischaemic penumbra, and it reignites hope for clinical application of the PWI/DWI mismatch. But the correlation between the mismatch, calculated by Coregistration mismatch method,and the clinical outcome of the patients with acute ischemic stroke is still unknown. so the investigators plan to conduct a prospective observational cohort study.

Multi-centre prospective study evaluating computed tomography angiography studies performed for stroke patients as a diagnostic and prognostic imaging biomarker.

Rationale: Over 20.000 people suffer an ischemic stroke in the Netherlands each year. Large artery occlusions are easy to identify and can be treated with endovascular clot removal. 70% of patient will however suffer from a more distal occlusion resulting in small volume stroke or a transient ischemic attack (TIA). Small ischemic lesions are hard to detect with current acute stroke protocols. TIA and small volume stroke patients, are at an increased risk for recurrent stroke, making immediate diagnosis critical. Because thrombo-embolic sources often cause these strokes, identifying and treating the underlying aetiology has the potential to radically lower the risk of recurrence and improve the outcome of these patients. Objectives: 1) To identify clinical and imaging predictors of recurrent stroke; 2) To improve early detection of small volume stroke with admission computed tomography perfusion (CTP) in patients with suspected acute ischemic stroke with small volume stroke or no ischemia on admission imaging. Study design: Prospective, multicenter cohort study. Study population: All patients who visited the University Medical Center (UMC) Utrecht, the Amsterdam University Medical Centers (Amsterdam UMC), location Academic Medical Center (AMC) or the St. Antonius Hospital and who underwent a CT-scan of the brain within 9 hours after onset of stroke symptoms with an age ≥18 years. Within 36 months, 720 patients will be enrolled in the study. Of these patients, 300 patients will be included for the follow-up magnetic resonance imaging (MRI). Main study parameters/endpoints: The main study endpoints are: 1) Stroke recurrence rate at 2 years; 2) Presence and volume of acute ischemic lesions on follow-up diffusion weighted imaging MRI.

stroke's risk is increased in patients with pulmonary embolism and PFO compared to patients without PFO. Does this increased risk persist years after pulmonary embolism ?

The main purpose of this trial is to observe whether Xingnaojing, intravenously administered within 24 hours of symptom onset on pre-hospital emergency ambulance, improves the Early neurological deterioration of acute stroke at 3 days.