Microclots and neutrophil activation as markers of stroke risk and reperfusion failure
Official title: Micro-clots and Neutrophil Activation as Potential Indicators for Stroke Risk and Reperfusion Failure The CLOTSAFE - Study (Micro-CLOTs, Stroke Risk, Activated Neutrophils, Reperfusion FailurE)
Run by University of Zurich · NCT06530927 · Data updated 2026-11-12
This project tries to see if tiny blood clots and activated neutrophils in blood can predict stroke risk and explain why some people with ischemic stroke don't improve after clot removal.
Quick facts
| Study type | Observational |
|---|---|
| Ages | 18 Years and up |
| Sex | All |
| Enrollment | 500 (estimated) |
| Sponsor | University of Zurich Academic / other |
| Locations | 1 site (Zurich, Canton of Zurich) |
| Status | Recruiting |
| Started | February 1, 2025 |
| Main results expected | September 1, 2030 |
| Study ends | December 1, 2030 |
| Registry record updated | August 29, 2025 |
| Trial ID | NCT06530927 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Ideal candidates are adults able to give consent who have confirmed ischemic stroke (within 12 hours of symptom onset for acute groups) or individuals at high risk of stroke, and who can attend the Zurich study site for blood sampling and imaging.
✕Probably not a fit
People under 18, pregnant individuals, those with hemorrhagic stroke, or patients unable to attend the Zurich site for required sampling and imaging are unlikely to benefit from participation.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
This prospective observational study will collect peripheral blood and clot material from up to 500 patients with acute and chronic ischemic stroke and from individuals at high risk of stroke. Researchers will use digital holotomography, atomic force microscopy, and micro-CT to characterize the size, shape, and surface properties of microclots and activated neutrophils. They will compare these structural and chemical features with clinical outcomes, stroke cause, and occurrence of reperfusion failure after mechanical thrombectomy. The goal is to identify blood-based markers that relate to capillary obstruction and poor recovery after otherwise successful recanalization.
Why it matters
Potential benefit: If successful, this work could help identify patients at higher risk of poor outcome after reperfusion and point to targets or strategies to improve microvascular flow and recovery.
How similar studies have gone: Preclinical rodent studies have shown that removing capillary stalls associated with neutrophils improves reperfusion and recovery, but human data are limited and this application in patients is relatively novel.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: Patients without acute stroke CS or CSG * No previous stroke or previous stroke ≥ 1 year ago * Signed informed consent Patients with acute stroke (AS-noTx, AS-IVT, AS-MT): * Patients admitted with high suspicion of acute ischemic stroke * Time of onset of stroke symptoms ≤ 12 hours * Consent according to the regulations of research in an emergency situation * Ischemic stroke later confirmed Exclusion Criteria: All groups: * Pregnancy * Age under 18 years Acute Stroke no Therapy • Acute treatment with IVT or with MT Acute Stroke IVT-Group • Acute treatment with MT or without IVT Acute Stroke MT-Group • Acute treatment without MT
Where it's running
-
University Hospital Zurich
Zurich, Canton of Zurich, Switzerland Recruiting
Study contacts
- Principal investigator: Susanne Wegener, Prof. — University Hospital Zurich, department Neurology
- Study coordinator: Lukas Otto, Dr. med.
- Email: lukasbastian.otto@usz.ch
- Phone: +41 43 253 13 01
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How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.