Clinical Research Directory

Stroke Cerebral Reorganization Pathways (SPECTRE)

SPECTRE is a prospective longitudinal study in order to identify whether patients with different degrees of motor recovery are distinguished by distinct brain post-stroke plasticity patterns in the acute and sub-acute phases. This study allows close longitudinal follow-up of patients with severe clinical motor impairment using functional MRI to study cerebral neuroplasticity after ischemic stroke in the acute and sub-acute phase in patients with upper limb motor impairement, taking into account prognostic criteria used in current practice.

Normal Saline Infusion After Intravenous Thrombolysis in Stroke

The intravenous administration of abundant normal saline is an easy-to-use strategy commonly employed to expand the blood volume. This study aimed to evaluate the efficacy and safety of the early administration of an abundant normal saline infusion after intravenous thrombolysis for promoting functional independence in patients with acute ischemic stroke. This multicenter, randomized, phase III clinical trial intends to enroll stroke participants who have undergone intravenous thrombolysis. Eligible patients are randomized to receive either abundant intravenous normal saline infusion (2,000-2,500 mL; normal saline group) or a small volume of intravenous normal saline infusion (≤600 mL; control group) immediately after thrombolysis. The primary outcome is the comparison of the ordinal modified Rankin Scale score at 90 days (±3) after randomization between the treatment groups.

earlY Upper Limb Rehabilitation WIth EEG-Neurofeedback After Stroke

The aim of this study is to evaluate the effect of early rehabilitation treatment by electroencephalographic neurofeedback on upper limb motor function after stroke. Researchers will compare : Interventional group: electroencephalographic neurofeedback + traditional reference rehabilitation programme Control group: SHAM electroencephalographic neurofeedback + traditional reference rehabilitation programme

Cardiac Assessment for Recurrent Stroke Risk Evaluation in Atrial Fibrillation

Background Atrial fibrillation (AF) is the most common cardiac arrhythmia, affecting up to 10% of the elderly. Ischemic stroke is the main complication of AF and cardioembolism is one of the leading causes of ischemic stroke, accounting for approximately one third of cases. Oral anticoagulant therapy (OAC) is a cornerstone in stroke prevention in patients with AF. According to randomized controlled trials of direct oral anticoagulants, a residual risk of ischemic stroke of 1-2% per year for so-called "breakthrough stroke" remains, despite adequate intake of OAC. The majority (\>70%) of these breakthrough strokes are cardioembolic in nature and only a minority are related to medication issues (e.g. non-compliance) or other, non-AF related etiologies. Stroke recurrence risk after such a breakthrough stroke markedly increases to 8-9% per year indicating a particularly high-risk situation. Why OAC fails in certain patients, but not in others remains as poorly understood, as does the reason why the subsequent risk of stroke is so high. Current risk stratification tools, such as the widely used CHA2DS2-VA(Sc)-score, fail to predict stroke risk in such a high-risk cohort, as they were intended to guide the initiation of OAC in low to moderate risk patients. In light of new therapeutic strategies currently being investigated, such as percutaneous left atrial appendage occlusion in patients with breakthrough strokes (ELAPSE - NCT05976685) or in AF-patients deemed high-risk (LAAOS IV - NCT05963698), improved risk stratification and characterization of high-risk AF patients is highly warranted. Several clinical factors, such as those reflected in the CHA2DS2-VA(Sc)-score, and especially a high AF-burden are associated with increased risk of cardioembolic stroke. Several cardiac serum biomarkers are thought to be surrogates not only of cardiac function, but also of cardioembolic risk. Reflecting ventricular and atrial wall tension, myocardial injury, oxidative stress and thrombogenicity, elevated NT-proBNP, MR-proANP, high-sensitive Troponin T and D-Dimers have all been associated with cardioembolic stroke in different AF and non-AF populations. As the main location of thrombus formation, the left atrium (LA) and more specifically its appendage (LAA) are of particular interest in the pathogenesis of cardioembolism. Pronounced LA-enlargement, compared to a normal-sized LA, correlates with an increased risk of cardioembolism in AF-patients. As over 80% of thrombi form within the LAA, several LAA-characteristics, such as slower LAA-flow velocity and larger LAA-orifice area have also been demonstrated to be associated with higher stroke risk. Although there is data on each one of these factors, they have only been investigated in low to moderate risk populations, such as AF-patients without prior stroke, OAC-naïve patients, or even within the general population as a whole. Their role in high-risk AF-patients and in breakthrough stroke is unknown. Hypothesis The investigators hypothesize that specific clinical factors, serum cardiac biomarkers and markers of LA- and LAA-morphology and function are associated with breakthrough stroke / OAC-failure and may improve risk stratification. Methods CARE-AF is a single-center, prospective cohort study conducted at the Stroke Center of the Inselspital, University Hospital Bern, Switzerland. Patients with an index ischemic stroke and AF (breakthrough and non-breakthrough cases) will be enrolled. The investigators will collect clinical data, serum cardiac biomarkers and echocardiographic indices of the LA and LAA. All patients will receive standardized annual follow-ups until the end of the study, defined as 12 months after the inclusion of the last participant. The primary endpoint is ischemic stroke or systemic embolism during follow-up. First, in a cross-sectional design, the study will assess the association between serum cardiac biomarkers and echocardiographic indices among patients with breakthrough vs. non-breakthrough stroke as index event, applying multivariate regression models. Second, the investigators will perform a longitudinal analysis assessing the association between the variables mentioned above and breakthrough stroke as index event with the primary endpoint, using multivariate Cox regression models. The study aims to enroll a minimum of 500 patients, which provides sufficient power to detect a clinically meaningful adjusted hazard ratio for recurrent stroke of 1.5 with 80% power at an alpha level of 5%. Conclusion The results of this project will enhance understanding of the role of specific clinical factors, cardiac serum biomarkers and echocardiographic indices in the residual risk of stroke in patients with AF on anticoagulation therapy. They may improve current risk stratification and have the potential to help guide therapeutic decisions in high-risk situations considering evolving therapeutic possibilities.

Searching for Explanations for Cryptogenic Stroke in the Young: Revealing the Etiology, Triggers, and Outcome

BACKGROUND: In industrialized countries a considerable and increasing proportion of strokes occur at younger ages. Stroke at young age causes marked disability at worst and thus long-standing socioeconomic consequences and exposes survivors for 4-fold risk of premature death compared with background population. Up to 50% of young patients with ischemic stroke remain without definitive etiology for their disease despite extensive modern diagnostic work-up (i.e. cryptogenic stroke). The group of cryptogenic strokes includes those with patent foramen ovale (PFO) or other abnormalities in the atrial septum in the heart as the only or concomitant finding. Population prevalence of PFO is high, 25%, and the mechanisms how PFO would be associated causally with ischemic stroke remain to be clarified. Moreover, there are only scarce data on clinical outcome, long-term risk of new vascular events, and prevention of such events in these patients. DESIGN: Searching for Explanations for Cryptogenic Stroke in the Young: Revealing the Etiology, Triggers, and Outcome (SECRETO) is an international prospective multicenter case-control study of young adults (age 18-49) presenting with an imaging-positive first-ever ischemic stroke of undetermined etiology (aim N=2000). Patients are included after standardized diagnostic procedures (brain MRI, imaging of intracranial and extracranial vessels, cardiac imaging, and screening for coagulopathies) and age- and sex-matched to healthy controls in a 1:1 fashion. Up to 45 study sites worldwide will be needed to recruit the planned participant population during a 3-year period. Neurovascular imaging and echocardiography studies, and ECGs will be read centrally. AIMS: SECRETO involves five principal fields of investigation: (1) Stroke triggers and clinical risk factors; (2) Long-term prognosis (new vascular events, functional and psychosocial outcomes); (3) Abnormalities of thrombosis and hemostasis; (4) Biomarkers of e.g. inflammation, atherogenesis, endothelial function, thrombosis, platelet activation, and hemodynamic stress to characterize postulated cryptogenic stroke mechanisms; and (5) genetic study, including genome-wide association and candidate gene studies as well as next-generation sequencing approach. All analyses consider cardiac functional and interatrial structural properties as a possible mediator. Furthermore, SECRETO Family Study (substudy) aims at collecting extensive family history of thrombotic events from informative patients being screened for SECRETO main study and collect genetic samples from all consenting family members for whole-genome sequencing. SIGNIFICANCE: SECRETO will provide novel information on clinical and subclinical risk factors, both transient and chronic, predisposing to cryptogenic ischemic stroke in young adults. This study also reveals long-term prognosis of this understudied patient population and may discover new genetic background underlying the disease mechanism and provide potential targets for drug development.

Therapy Evaluation in Patients With Minor Stroke and Large Vessel Occlusion

This multicenter registry study, which record the therapy strategy and follows up these acute ischemic stroke (AIS) patients with low NIHSS and large vessel occlusion (LVO), is intended to provide the important data for therapy evaluation and prognostic prediction of the LVO patients with low NIHSS.

For Patients With Ischemic Stroke, Clinically Study the Effectiveness and Safety of Butylphthalide.

This is a prospective, open, single-arm, the real world of clinical trials. The researchers plan to recruit 300 eligible patients. The main purpose of this study is to evaluate the effectiveness and safety of butylphthalide in the treatment of ischemic stroke, and to establish a population pharmacokinetic model of butylphthalide in elderly patients to explore its blood drug concentration. Correlation with its efficacy and adverse reactions.