The Interplay of Microcirculation and Plasticity After Ischemic Stroke

Microcirculation and Plasticity After Stroke

Sponsors

Lead sponsor: University of Zurich

Source University of Zurich
Brief Summary

Reperfusion is the main goal of early medical interventions after stroke, such as thrombolysis and thrombectomy. Recanalization works only if applied early - the earlier the better, but with a statistical cutoff of 4.5 hours where risk of hemorrhage outweighs the benefit. Recently, this cutoff has been put into perspective using standardized perfusion measurements by magnetic resonance imaging (MRI) or computed tomography (CT). Two trials have shown that revascularization is beneficial up to 24 hours after stroke onset if patient selection is based on perfusion imaging. This suggests interindividual differences in the temporal evolution of an infarction. One explanation for interindividual differences is the variability of the collateral blood supply to the brain, which in turn can maintain different perfusion pressures around the infarct core, also called the penumbra region. Insufficient recruitment of these collateral pathways is an independent negative predictor of poor outcome; the insufficiency may in part be explained by insufficient dilatation of arterioles ("low dilator reserve"). So far, interventions to improve collateral perfusion, e.g., induced hypertension, have not demonstrated effectiveness, likely because our understanding of collateral perfusion, demand-dependent dilatation of arteries (cerebrovascular reserve, CVR) and their effect on microcirculation is insufficient.

Functional recovery after a brain lesion is based on plasticity. Plasticity involves the creation of new synapses, fibers (axons and dendrites) and lasting modification to synaptic strength as well as the formation and migration of new neurons. In the cortex surrounding an infarct, plasticity is facilitated by ischemia via modification of gene expression, i.e. a certain time window after stroke, and is stimulated by activity and training. Tissue microcirculatory status and perfusion surrounding the stroke lesion may play a role in the formation of this plasticity. The investigators will analyze the contributions of pre-existing vascular networks, the impact of stroke-affected vessels, timing and degree of recanalization success, brain excitability, and short-term intra-cortical inhibition to better understand how these factors relate to functional recovery after stroke.

Overall Status Recruiting
Start Date October 7, 2019
Completion Date January 31, 2022
Primary Completion Date January 31, 2022
Study Type Observational
Primary Outcome
Measure Time Frame
Change in brain microcirculation <36 and 50 hours; 7, 45 and 90 days after stroke onset
Change in brain plasticity 7, 45 and 90 days after stroke onset
Secondary Outcome
Measure Time Frame
National Institutes of Health Stroke Scale <36 and 50 hours; 7, 45 and 90 days after stroke onset
Fugl-Meyer Motor Assessment - Upper Extremity Subscale 50 hours; 7, 45 and 90 days after stroke onset
Fugl-Meyer Motor Assessment - Lower Extremity Subscale 50 hours; 7, 45 and 90 days after stroke onset
Finger extension 1 <36 and 50 hours; 7, 45 and 90 days after stroke onset
Finger extension 2 <36 and 50 hours; 7, 45 and 90 days after stroke onset
Finger extension 3 <36 and 50 hours; 7, 45 and 90 days after stroke onset
Trunk Control Test 50 hours; 7 and 90 days after stroke onset
Functional Ambulation Categories <36 and 50 hours; 7, 45 and 90 days after stroke onset
Ten-Meter Walk Test 7, 45 and 90 days after stroke onset
Modified Rankin Scale <36 and 50 hours; 7, 45 and 90 days after stroke onset
Mobilization <36 and 50 hours; 7 days
Concomitant movement therapy <36 and 50 hours; 7, 45 and 90 days after stroke onset
Related Serious Events <36 and 50 hours; 7, 45 and 90 days after stroke onset
Enrollment 49
Condition
Intervention

Intervention type: Other

Intervention name: Observation of microcirculation and plasticity of the brain

Description: Assessment of microcirculation, brain plasticity and clinical function

Arm group label: Single-group study

Eligibility

Sampling method: Probability Sample

Criteria:

Inclusion Criteria:

- ≤36h First-ever clinical ischemic stroke at hospital admission

- Occlusion of M1-segment of the middle cerebral artery, and/ or intracranial internal carotid artery

- 18 years or above

- Living independent before stroke (mRS ≤3)

- Written informed consent of the patient or the when the patient is not able to participate in the consenting procedure, the written authorization of an independent doctor who is not involved in the research project to safeguard the interests of the patient; in that case, post-hoc written informed consent of the patient is needed, or when the patient remains unable to participate in the informed consent procedure, written informed consent of a next of kind

Exclusion Criteria:

- Major cardiac, psychiatric and/ or neurological diseases

- Early seizures

- Known or suspected non-compliance, drug and/ or alcohol abuse

- Contra-indications for Magnetic Resonance Imaging and Transcranial Magnetic Stimulation, such as a history of seizure, prior electroconvulsive therapy, deep brain stimulators or other metal in the head, skull defect, pacemaker; neuroleptic medication; known allergic reaction to contrast material

- Documented evidence that the patient does not want to participate in any scientific study or, in case of lack of documented evidence, no behavior and/or expression(s) that indicate(s) refusal of the patient to participate in research

Gender: All

Minimum age: 18 Years

Maximum age: N/A

Healthy volunteers: No

Overall Official
Last Name Role Affiliation
Andreas R Luft, Prof. MD Study Chair University of Zurich, University Hospital Zurich
Overall Contact

Last name: Janne M Veerbeek, PhD

Phone: +41 (0)43 253 01 54

Email: [email protected]

Location
facility status contact contact_backup
University Hospital Zurich Recruiting Janne M. Veerbeek, PhD +41(0)43 253 01 54 [email protected]
Location Countries

Switzerland

Verification Date

November 2019

Responsible Party

Responsible party type: Sponsor

Keywords
Has Expanded Access No
Condition Browse
Arm Group

Arm group label: Single-group study

Description: Assessment of microcirculation, brain plasticity and clinical function

Acronym IMPreST
Patient Data Undecided
Study Design Info

Observational model: Cohort

Time perspective: Prospective

Source: ClinicalTrials.gov