Active clinical trials for "Ischemic Attack, Transient"

Patient Registration Study of Acute Ischemic Stroke/transient ischemic attack(TIA) With Atrial Fibrillation (AISWAF) is a single-center prospective, consecutively, observational study, was conducted in patients with acute ischemic stroke/TIA with atrial fibrillation. The aim of this study was to understand the stroke mechanism, the regularity of stroke recurrence and its influencing factors, to establish a risk stratification model for stroke recurrence, and to preliminarily explore the relationship between stroke mechanism, risk stratification and antithrombotic regimen in this population.

Stroke has become the leading cause of death in China. It has been shown that intracranial artery stenosis (ICAS) plays a key role in Chinese stroke patients. Although most of stenotic diseases in intracranial arteries are atherosclerotic, a substantial number of other vascular diseases, such as dissection, arteritis, moyamoya disease, and reversible cerebral vasoconstriction syndrome (RCVS), can also lead to intracranial artery luminal narrowing. It is challenging to differentiate the etiologies of ICAS relying on measuring luminal narrowing by angiographical approaches. In addition, the progression of intracranial atherosclerotic disease (ICAD) has been demonstrated to be highly associated with the risk of ischemic cerebrovascular events. However, the influence factors for ICAD progression remains unclear. High-resolution magnetic resonance imaging (HR-MRI) has been widely used to assess ICAS diseases. The different etiologies of ICAS are differentiable by MR-MRI according to the features of location, shape, signal pattern, remodeling, and contrast enhancement. Investigators have proved that HR-MRI is a reproducible technique that may be reliably utilized to monitor the changes of ICAD during natural follow-up or medical treatment. The ICASMAP (Intracranial Artery Stenosis MR Imaging: Aetiology and Progression) is a prospective, cross-sectional, observational, and multicenter study. The objectives of ICASMAP are to determine: 1) the spectrum of etiology of ICAS in stroke patients; and 2) the influence factors for progression of ICAD. A total of 300 patients with symptomatic stenotic disease in intracranial arteries (stenosis range: 30%-99%) will be recruited within two weeks after symptom onset from 18 different hospitals across Beijing-Tianjin-Hebei region in China within 1 year. All the patients will undergo HR-MRI for intracranial arteries at baseline, one-year, and two-years. The clinical risk factors will be collected and blood draw will be conducted. The ICASMAP study may help to improve the precise diagnosis and intervention of ICAS and stroke prevention.

Study of heterogeneity in associations between social deprivation and the initial presentation of 12 cardiovascular diseases.

Serum uric acid level is a commonly measured biomarker. The association between serum uric acid level and the risk of developing cardiovascular diseases has been observed in some studies, while others showed controversial results. Estimation of this association may help to predict cardiovascular outcomes and may guide new treatment strategies. The hypothesis is that increased serum uric acid level is associated with a range of cardiovascular diseases.

The prevalence of patent foramen ovale (PFO) is about 25% in the general population and approximately 40% in patients who have ischemic stroke of unknown cause (cryptogenic stroke). Given the large number of asymptomatic patients, no primary prevention is currently recommended. On the contrary, secondary prevention is very important. Prospective studies have shown that antithrombotic treatment (ATT) with aspirin or warfarin appears to negate the risk of recurrent stroke associated with a PFO. Patients with spontaneous or large right-to-left shunts (RLS), those with a coinciding atrial septal aneurysm (ASA) or multiple ischemic events prior to the PFO diagnosis may still be at increased risk of stroke recurrence despite ATT. Percutaneous device closure (PDC) is a challenging alternative to ATT. Several studies reported 0% to 3.4% annual recurrence rates of stroke or TIA in patients treated by PDC. To date, there is no data from randomized controlled trials (RCT) comparing the risk of stroke recurrence after PDC with that under ATT only. The results from ongoing RCTs are not to be awaited in the near future, mainly due to low enrolment and event rates. Alternative data-gathering strategies such as multicenter registries are needed to overcome the low recruitment rates. The aim of the present study is to compare the risk of recurrent stroke and TIA in patients with PFO and otherwise unexplained stroke who undergo PDC or receive ATT.

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.

STANDARDIZED PHYSICAL ACTIVITIES MEASURED BY ACCELEROMETERS Background and aims: Physical activity may be assessed by several different methods. However, the use of accelerometers is the most direct method available for real-time measurements. The piezoelectric element of accelerometers records an electric voltage during movement which is then transcribed to Activity Counts (AC). Few studies have used Actical accelerometers to assess standardized physical activities and most of these were not applicable to patients in a hospital setting. No previous studies have applied Actical accelerometers to the wrists or ankles during standardized activities. The aim of this study is to record AC during different standardized activities frequently done by patients hospitalized for acute ischemic stroke. Methods: Patients discharged since February 2012 after a transient ischemic attack have been invited to participate in the study scheduled for June-September 2012 (nexpected=25). All participants wear 5 accelerometers (Actical), one at each wrist and ankle and one over the hip. Standardized physical activities include: treadmill walking (5 minutes, 1 and 4km/h) staircase walking (1 floor, normal pace) cycling with fixed load (5 minutes) standing up from sitting position and sitting down again (x5) standing up from supine position turning from left to right and back while lying in bed raising outstretched arm 90° (x5, standing position) eating (5 minutes, sitting position) drinking a glass of water sleeping (6 hours)

In this protocol, the investigators present methods and preliminary results from the PLATFORM-CVD Study, an EHR-based multicenter cohort. This study will focus on assessing the distribution of major cerebrovascular diseases, determining the risk factors associated with disease incidence and worse in-hospital outcomes, as well as describing the quality of care. Data from this cohort will be used to develop suitable prediction models for cerebrovascular diseases using real-world data and to understand how outcomes for cerebrovascular diseases would change with quality improvement interventions.

The purpose of this study is to determine whether the ABCD2 score can be used in patients with transient ischemic attack, admitted to Beijing anzhen hospital, to evaluate the prognosis, risk factor of those patients.

wide range of diagnoses may present like stroke, called stroke mimics as well as transient ischemic attacks .