Transmission Electron Microscopy Images for Platelet Ultrastructural Criteria Before and After the Onset of an Antiplatelet Agent

Study Overview
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Brief Summary
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The aim of the pilot study is to collect all the ultrastructural platelet characteristics by transmission electron microscopy before and after the onset of an antiplatelet treatment in patients hospitalized for an ischemic stroke ; and to assess recurrence of Ischemic Cerebral Accident (ICA) at 6 months in patients hospitalized for Ischemic stroke.

Detailed Description
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Ischaemic stroke is the leading cause of adult disability. Thus, a strategy based on an efficient antiplatelet therapy has been developed to prevent platelet activation occurring in the acute phase of non-cardioembolic ischemic stroke. The biological monitoring of the antiplatelet therapy with available platelet function assays do not provide a global integrative approach considering all the mechanisms involved in platelet activation. Platelet transmission electron microscopy recently validated for assessing distinct ultrastructural abnormalities is a reliable morphological platelet structural analysis tool. Ultrastructural criteria could be identified and be useful for the assessment of the degree of platelet activation and thus the biological efficiency of antiplatelet agents. All the activation transduction signals are integrated and all antiplatelet agents can be assessed. The aim of the pilot study is to collect all the ultrastructural platelet characteristics by transmission electron microscopy before and after the onset of an antiplatelet treatment in patients hospitalized for an ischemic stroke. Investigators expect to identify ultrastructural characteristics that will be correlated with the platelet degree of activation to guide clinicians in decision-making regarding the antiplatelet therapy strategy.

Official Title
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Transmission Electron Microscopy Images for Platelet Ultrastructural Criteria Before and After the Onset of an Antiplatelet Agent

Conditions
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Ischemic Stroke

Intervention / Treatment
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* Biological: Blood collection before antiplatelet treatment
* Biological: Blood collection after antiplatelet treatment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Social security affiliation Signed informed consent patients hospitalized for an non cardioembolic ischemic stroke requiring the onset of an antiplatelet therapy according to the usual guidelines recommendations Exclusion Criteria: Contraindications regarding antiplatelet agent(s) and/or at least one excipient according to Summary of Product Characteristics (SPC).

Ages Eligible for Study
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Minimum Age: 18 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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Design Details

Primary Purpose: Prevention
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Ischemic stroke patients<br>Patients hospitalized for an ischemic stroke. | Biological: Blood collection before antiplatelet treatment<br>* Blood sample (17ml) will be collected in the neurovascular department to be processed for platelet ultrastructural analysis before the onset of an antiplatelet treatment<br>Biological: Blood collection after antiplatelet treatment<br>* A follow-up will be carried out 5 to 8 days after the initiation of the treatment. A blood test will be taken in the NeuroVascular Unit<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Morphology of the platelet : | Platelet ultrastructural criteria will be obtained from transmission electron microscopy images of platelet ultrathin sections before and after (5 days) initiation of antiaggregant therapy in patients with noncardioembolic ICA the morphology of the platelet : discoid or round with the emission of filipodia, pseudopodia and lamellipodia | Day 5 | 
| Type of granules in the platelet | Platelet ultrastructural criteria will be obtained from transmission electron microscopy images of platelet ultrathin sections before and after (5 days) initiation of antiaggregant therapy in patients with noncardioembolic ICA - the observation of granules : alpha granules dense granules | Day 5 | 
| Distribution of mitochondria, glycogen and dense tubular system in platelets | Platelet ultrastructural criteria will be obtained from transmission electron microscopy images of platelet ultrathin sections before and after (5 days) initiation of antiaggregant therapy in patients with noncardioembolic ICA | Day 5 | 
| Structure of open canalicular system in platelets | Platelet ultrastructural criteria will be obtained from transmission electron microscopy images of platelet ultrathin sections before and after (5 days) initiation of antiaggregant therapy in patients with noncardioembolic ICA - the open canalicular system dilated or not associated with degranulation or not | Day 5 | 
| Number of patients with a microtubular ring on the equatorial section plane (peripheral or centralized) in platelets | Platelet ultrastructural criteria will be obtained from transmission electron microscopy images of platelet ultrathin sections before and after (5 days) initiation of antiaggregant therapy in patients with noncardioembolic ICA | Day 5 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of a composite endpoint | The incidence of a composite of cardiovascular events (radiologically documented recurrent ischemic stroke, transient ischemic attacks, coronary artery disease (acute coronary syndromes, myocardial infarction), obliterating arterial disease of the lower limb, death of cardiovascular origin) | Month 6 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Ischemic stroke, Ultrastructural characterization, Transmission electron microscopy, platelet dysfunction, Blood Coagulation Disorder