Administration of eptifibatide to acute coronary syndrome patients receiving enoxaparin or unfractionated heparin: Effect on platelet function and thrombus formation

• Published in: Journal of the American College of Cardiology 2004-03, Vol.43 (6), p.966-971
• Main Authors: LEV, Eli I, HASDAI, David, SCAPA, Erez, TOBAR, Ana, ASSALI, Abid, LAHAV, Judith, BATTLER, Alexander, BADIMON, Juan J, KORNOWSKI, Ran
• Format: Article
• Language: English
• Subjects: Acute coronary syndromes; Angina pectoris; Anticoagulants - administration & dosage; Anticoagulants - pharmacology; Anticoagulants - therapeutic use; Biological and medical sciences; Blood Cell Count; Cardiology; Cardiology. Vascular system; Coronary Angiography; Coronary heart disease; Drug therapy; Drug Therapy, Combination; Enoxaparin - administration & dosage; Enoxaparin - pharmacology; Enoxaparin - therapeutic use; Female; Heart; Heart attacks; Heparin - administration & dosage; Heparin - pharmacology; Heparin - therapeutic use; Humans; Male; Medical sciences; Middle Aged; Myocardial Infarction - diagnostic imaging; Myocardial Infarction - drug therapy; Myocardial Infarction - pathology; Partial Thromboplastin Time; Peptides - administration & dosage; Peptides - pharmacology; Peptides - therapeutic use; Platelet Aggregation - drug effects; Platelet Aggregation Inhibitors - administration & dosage; Platelet Aggregation Inhibitors - pharmacology; Platelet Aggregation Inhibitors - therapeutic use; Platelet Glycoprotein GPIIb-IIIa Complex - antagonists & inhibitors; Treatment Outcome; Venous Thrombosis - prevention & control
• ISSN: 0735-1097; 1558-3597
• DOI: 10.1016/j.jacc.2003.09.060

The goal of this study was to compare the antithrombotic effects of enoxaparin versus unfractionated heparin (UFH) when combined with eptifibatide in acute coronary syndrome (ACS) patients. An increasing number of high-risk ACS patients are treated with low-molecular-weight heparin and a glycoprotein (GP) IIb/IIIa inhibitor. There is a paucity of data regarding the antithrombotic properties of such a combination as compared with UFH and GP IIb/IIIa inhibitors. Twenty-six ACS patients scheduled to undergo coronary angiography were treated with subcutaneous enoxaparin (n = 13) or intravenous UFH (n = 13). All patients received eptifibatide just before coronary angiography. Antithrombotic effects were assessed as changes in platelet-thrombus formation using the Badimon ex vivo perfusion chamber. Perfusions were carried out at a high shear rate (HSR) and a low shear rate (LSR). Patients underwent two perfusion studies: at baseline (under enoxaparin or UFH) and 10 min after the eptifibatide bolus. Platelet function was evaluated by ADP-induced platelet aggregation and the rapid platelet function analyzer. Both therapeutic combinations achieved a marked reduction in platelet aggregation after eptifibatide (83% to 89.7% reduction in the enoxaparin-eptifibatide group and 77.8% to 85.5% reduction in the UFH-eptifibatide group, inter-group differences not significant). Both groups also demonstrated marked reductions in thrombus formation, but the reductions achieved in the enoxaparin-eptifibatide group were significantly higher than those achieved in the UFH-eptifibatide group (HSR: 75.6% reduction vs. 63.9%, respectively, p = 0.01; LSR: 79.7% reduction vs. 66.1%, respectively, p = 0.0001). The combination of eptifibatide with enoxaparin appears to have a more potent antithrombotic effect than that of eptifibatide and UFH in the doses tested.