Abstract Details

Title Post-loading (Day 3) Platelet CXCR7 Predicts Long-term Vascular Recurrence After Ischemic Stroke: A Prospective Cohort Study

Topic Cerebrovascular Disease and Interventional Neurology

Presentation(s) P10 - Poster Session 10 (8:00 AM-9:00 AM)

Poster/Presentation
Number 5-015

Objective We evaluated whether baseline and post-loading (Day 3) platelet activation profiles predict long-term
recurrence of acute ischemic stroke and other vascular events.

Background Patients with ischemic stroke face a substantial 3-4% annual risk of recurrent vascular events despite guideline-directed secondary prevention. Conventional clinical scores (e.g., Essen, SPI-II) summarize demographics and co-morbidities but do not capture patient-specific thrombotic biology. We evaluated whether baseline and post-loading (Day 3) platelet activation profiles predict long-term
recurrence.

Design/Methods This was a single-centre prospective cohort study at the National University Hospital,
Singapore, enrolling adults with non-cardioembolic ischemic stroke. Platelet activation markers were
quantified by flow cytometry in isolated platelets at presentation, and Day 3 after guideline-directed antiplatelet loading. Age-matched healthy individuals served as controls. The prespecified primary outcome was a composite of ischemic stroke/TIA, myocardial infarction, peripheral arterial occlusion, vascular death over 5 years, adjudicated quarterly. Multivariable Cox models (adjusted for age, stroke severity, and antiplatelet regimen) assessed associations between markers and outcome. Multiple-
marker testing was controlled by false-discovery rate.

Results 381 patients (mean age 58.9 years, 74% male) were enrolled with median follow-up 47 months; 100 events occurred (26.2%). Relative to 50 healthy controls, 8/10 platelet activation markers were elevated at baseline. By Day 3, antiplatelet therapy reduced several platelet activation markers (CLEC-2, COX-1, GPVI, PAC-1, SDF-1, and CD154), whereas CXCR7, CD62P, COX-2, and P2Y12 remained persistently high. In adjusted analyses, Day 3 platelet CXCR7 independently predicted recurrence (HR 2.34; 95% CI 1.02–5.35; p = 0.045), while baseline markers were not predictive.

Conclusions A residual CXCR7-linked platelet signature persists despite standard antiplatelet therapy. Day 3 platelet CXCR7 independently predicts long-term vascular recurrence and merits prospective validation, alongside mechanistic studies to determine whether
CXCR7-pathway modulation can reduce residual thrombotic risk.

Authors/Disclosures
Kevin Soon Hwee Teo, MA, MB, BChir, MRCP (National University Health System of Singapore) PRESENTER	Kevin Soon Hwee Teo, MA, MB, BChir, MRCP has nothing to disclose.
OOIEAN W. TENG, PhD	Dr. TENG has nothing to disclose.
Bernadette Er, RN	Ms. Er has nothing to disclose.
Amy M. Quek, MBBS (National University Hospital)	The institution of Dr. Quek has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Merck. The institution of Dr. Quek has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Roche. The institution of Dr. Quek has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Astra Zeneca. The institution of Dr. Quek has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Roche. The institution of Dr. Quek has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Merck. The institution of Dr. Quek has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Astra Zeneca.
Raymond C. Seet, MD (National University of Singapore)	Dr. Seet has nothing to disclose.

��ɫ��

��ɫ��