Platelet activation determined by flow cytometry persists despite antithrombotic therapy in patients with unstable angina and non-Q-wave myocardial infarction
- 1 February 1994
- journal article
- research article
- Published by Springer Science and Business Media LLC in Journal of Thrombosis and Thrombolysis
- Vol. 1 (1), 95-100
- https://doi.org/10.1007/bf01062002
Abstract
Background: Current strategies in the treatment of patients with acute coronary syndromes include antiplatelet agents and thrombin antagonists, most commonly aspirin and heparin, respectively. Cardiac events, however, occur despite what is considered to be maximal medical treatment.Methods: We determined the percentage of activated platelets in whole blood samples taken from 22 patients with unstable angina and non-Q-wave myocardial infarction participating in the TIMI III B trial. Platelet activation was assessed using a monoclonal antibody to the surface-expressed α-granule protein, P-selectin, and flow cytometry. All patients received a full complement of antiischemic medications as well as intravenous heparin and oral aspirin, and were then randomized to tissue plasminogen activator or placebo.Results: Platelet activation prior to randomization was increased threefold to fourfold compared with healthy volunteers (11.4 ± 11.4% vs. 2.5 ± 2.0%; p < 0.01). Serial measurements performed 12, 24, 48, and 96 hours after treatment initiation revealed that platelet activation persisted. No differences in patients experiencing recurrent ischemic events (n=9) or those randomized to a 90-minute, accelerated infusion of tissue plasminogen activator (n=12) were observed.Conclusions: A modest degree of platelet activation is seen for at least 96 hours and possibly longer in patients with unstable angina and non-Q-wave myocardial infarction, despite being treated with intravenous heparin and oral aspirin. These findings support current efforts to identify more potent and selective antithrombotic treatment strategies.Keywords
This publication has 41 references indexed in Scilit:
- Effects of nitroglycerin at therapeutic doses on platelet aggregation in unstable angina pectoris and acute myocardial infarctionThe American Journal of Cardiology, 1990
- Aspirin, Heparin, or Both to Treat Acute Unstable AnginaNew England Journal of Medicine, 1988
- Fiberoptic observation of thrombosis and thrombolysis in isolated human coronary arteriesAmerican Heart Journal, 1986
- Platelet Activation in Unstable Coronary DiseaseNew England Journal of Medicine, 1986
- Coronary Angioscopy in Patients with Unstable Angina PectorisNew England Journal of Medicine, 1986
- Aspirin, Sulfinpyrazone, or Both in Unstable AnginaNew England Journal of Medicine, 1985
- Fibrinopeptide A: a marker of acute coronary thrombosis.Cell Metabolism, 1985
- Unstable angina with fatal outcome: dynamic coronary thrombosis leading to infarction and/or sudden death. Autopsy evidence of recurrent mural thrombosis with peripheral embolization culminating in total vascular occlusion.Cell Metabolism, 1985
- Protective Effects of Aspirin against Acute Myocardial Infarction and Death in Men with Unstable AnginaNew England Journal of Medicine, 1983
- Comparison of the antithrombotic action of calcium antagonist drugs with dipyridamole in dogsThe American Journal of Cardiology, 1983