These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Heparin-induced thrombocytopenia: the role of platelet activation and therapeutic implications.
    Author: Haas S, Walenga JM, Jeske WP, Fareed J.
    Journal: Semin Thromb Hemost; 1999; 25 Suppl 1():67-75. PubMed ID: 10357155.
    Abstract:
    In the past, heparin has been the sole anticoagulant for interventional cardiovascular procedures. Today, several alternate approaches to anticoagulate patients with heparin-induced thrombocytopenia (HIT) are under consideration. Antiplatelet drugs, such as the ADP receptor antagonists and inhibitors of glycoprotein (GP) IIb/IIIa, are currently in development. We investigated the effect of two anti-platelet agents on platelet activation induced by HIT serum (n = 5 HIT positive sera, n = 5 HIT negative sera and n = 4 donor platelets) and heparin, using the traditional platelet aggregation assay, a Lumi-aggregation assay to also determine platelet release, and flow cytometry. By all methods, the GP IIb/IIIa inhibitor-GPI 562 (Novartis; Nürnberg, Germany)-produced a concentration dependent (6.25 to 125 ng/mL) decrease in platelet activation, as shown by platelet aggregation, platelet microparticle formation, P-selectin expression, and ATP release. Similar results were obtained with the thienopyridine ADP receptor antagonist ticlopidine (Sanofi Recherche; Toulouse, France) in vitro at high concentrations of 5.0 to 50 microg/mL and ex vivo in a patient dosed at 250 mg/day. These studies show that GP IIb/IIIa and ADP receptor inhibitors can block platelet activation induced by HIT serum/heparin, providing evidence that the mechanism of HIT may be multifactorial involving not only the generation of the heparin-PF4 or other antibodies but also involving platelet-specific processes and, potentially, the generation of proaggregatory substances. The new antiplatelet agents may be useful in the clinical management of HIT patients.
    [Abstract] [Full Text] [Related] [New Search]