Platelet Expression of FcγRIIa and Arterial Hemodynamics to Predict Recurrent Stroke in Intracranial Atherosclerosis

Launched by UNIVERSITY OF CALIFORNIA, LOS ANGELES · Aug 24, 2022

Keywords

ClinConnect Summary

This clinical trial is studying whether certain levels of a protein found on platelets, called FcγRIIa, can help predict the risk of having another stroke in people who have a specific type of narrowing in their brain arteries known as intracranial atherosclerosis. The researchers want to find out if those with higher levels of this protein might be at a greater risk for future ischemic events, which are caused by reduced blood flow to the brain.

To be eligible for this study, participants must be at least 30 years old and have experienced either a stroke or a transient ischemic attack (TIA), which is a temporary episode of stroke-like symptoms. They should also have imaging results that confirm their condition. Participants will need to provide informed consent and may undergo imaging tests like MRIs. The trial is currently recruiting individuals of all genders, and it aims to better understand how to identify patients who might need extra care to prevent future strokes. If you or a loved one are considering participating, it could be an opportunity to contribute to important research while also potentially benefiting from close medical monitoring.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • Stroke is defined as symptoms lasting \>24 hours and associated with imaging evidence of acute ischemia in the distribution of the stenotic vessel on head CT or brain MRI. Minor stroke is defined as NIHSS\<6, as used in prior studies.
• • Eligible TIA, defined as transient neurological symptoms lasting \<24 hours, need to be: a) accompanied by DWI abnormalities in the distribution of the stenotic artery; or b) multiple (\>1), stereotyped events associated with unequivocal ischemic symptoms (i.e. weakness, aphasia, diplopia), and attributed to the symptomatic artery. The intent of these restrictive inclusion criteria for TIA is to exclude potential stroke mimics.
• • ICAD should involve the intracranial carotid, middle cerebral, intracranial vertebral or basilar arteries. Isolated anterior and posterior cerebral artery stenosis is not included as it is uncommon in these locations and non-invasive criteria for high-grade ICAD are not well established for these vessels.
• • Stenosis 50-99% will be quantified by CTA. The criteria for 50-99% are: measured stenosis by WASID criteria (percent stenosis = (1-\[diameter stenosis/diameter normal\]) x 100%.
• • Age ³30; those 30-49 years of age must also have the presence of established atherosclerotic disease in another vascular bed (coronary, extracranial carotid, peripheral) or the presence of 2 or more risk factors (hypertension, diabetes mellitus, hyperlipidemia, tobacco abuse within the last 2 years). The rationale for this criterion is to exclude non-atherosclerotic vasculopathies.
• • Provide informed consent for participation in the study.
• Exclusion Criteria:
• • Other determined etiology or established cause of the acute stroke or TIA: atrial fibrillation, mitral stenosis, mechanical valve, intracardiac thrombus or vegetation, dilated cardiomyopathy or ejection fraction \<30%, proximal extracranial carotid or vertebral stenosis \>50%.
• • Contraindications to MRI, including MR-incompatible metallic implants (i.e. certain artificial cardiac valves, penile implants, other prosthesis), implanted electronic devices (i.e. pacemaker/defibrillator, neurostimulators, cochlear implants), other potentially mobile ferromagnetic material (i.e. shrapnel, magnetic aneurysm clips), pregnancy (women in fertile age should have a negative pregnancy test), lactation, morbid obesity, and severe claustrophobia.