The Xylum Clot Signature Analyzer: a dynamic flow system that simulates vascular injury

Area of Science:

• Hematology
• Biomedical Engineering
• Medical Diagnostics

Background:

• Assessing hemostasis requires evaluating platelet function and coagulation.
• Existing methods may not fully replicate physiological conditions.
• A user-friendly analyzer for near-physiological hemostasis assessment is needed.

Purpose of the Study:

• To evaluate the Xylum Clot Signature Analyzer (CSA) for assessing platelet function and coagulation.
• To determine if CSA parameters reflect platelet function and coagulation under physiological flow and temperature.
• To investigate the role of shear rate and specific inhibitors on CSA measurements.

Main Methods:

• The CSA analyzes non-anticoagulated whole blood in a single venipuncture.
• Measurements include platelet hemostasis time (PHT), collagen-induced thrombus formation (CITF), and clotting time (CT).
• Blood samples were tested with varying shear rates and inhibitors (anti-vWF, anti-GPIb, ATA, anti-GPIIb-IIIa, heparin).

Main Results:

• PHT and CITF increased at lower shear rates, indicating shear-dependent platelet activation.
• Inhibitors targeting von Willebrand factor (vWF) and platelet receptors prolonged PHT and CITF, especially at high shear rates.
• Heparin significantly increased clotting time (CT), demonstrating inhibition of coagulation under flow.

Conclusions:

• The CSA accurately assesses multiple critical aspects of hemostasis in whole blood.
• CSA parameters reflect platelet function and coagulation under near-physiological flow conditions.
• The analyzer is sensitive to shear-induced platelet activation and the effects of hemostatic inhibitors.