Primary haemostasis: platelets and von Willebrand factor
Platelet adhesion, activation and aggregation, the roles of von Willebrand factor and ADAMTS13, where antiplatelet drugs and desmopressin act, and how to read VWF and platelet function tests.
Tier 2Medical sciences concept
Written with AI assistance and fact-checked against the sources below. For exam study, not clinical decisions. How notes are made
At a glance
- Primary haemostasis forms the platelet plug within seconds to minutes. Secondary haemostasis (see coagulation physiology) reinforces it with fibrin.
- Three steps: adhesion (GPIb to VWF, GPVI to collagen), activation (TXA2, ADP, thrombin, granule release) and aggregation (GPIIb/IIIa to fibrinogen).
- VWF links platelets to collagen under high shear and carries factor VIII.
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Sources
- ASH ISTH NHF WFH 2021 guidelines on the diagnosis of von Willebrand diseaseBlood Advances (James et al., 2021;5:280-300), 2021
- Von Willebrand's diseaseNew England Journal of Medicine (Leebeek and Eikenboom, 2016;375:2067-2080), 2016
- Postgraduate Haematology (7th ed.)Wiley-Blackwell (Hoffbrand, Higgs, Keeling and Mehta, 2016), 2016
- Hoffbrand's Essential Haematology (8th ed.)Wiley-Blackwell (Hoffbrand and Steensma, 2019), 2019
- Last updated
- 14 November 2026
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