Clinical Significance of Thrombocytopenia During a Non–ST-Elevation Acute Coronary Syndrome

Abstract

Although causality between thrombocytopenia and adverse clinical events could not be established definitively, thrombocytopenia was highly correlated with both bleeding and ischemic events, and the presence of this condition identified a more-at-risk patient population.

Evidence that thrombocytopenia observed in humans treated with orally bioavailable glycoprotein IIb/IIIa antagonists is immune mediated

“…Thrombocytopenic patients experienced more bleeding events and ischemic events. 3,4 Thrombocytopenia has been observed with all intravenous agents currently in clinical use. For example, abciximab administration has been associated with the development of thrombocytopenia at rates between 2.5% and 5.6%, and with acute, potential life-threatening profound thrombocytopenia at rates between 0.3% to 0.8%.…”

“…3,11 In general, patients with thrombocytopenia are older, weigh less, have a lower baseline platelet count, and are treated with bolus and infusion. 3,4 To extend the benefits of the acute therapy to long-term care, a number of oral GP IIb/IIIa antagonists have undergone clinical trials. For example, RPR 109891 therapy was associated with a thrombocytopenia frequency of up to 13%.…”

Glycoprotein IIb/IIIa Inhibitor-Associated Thrombocytopenia: Clinical Predictors and Effect on Outcome

“…Previous studies have shown that thrombocytopenia is associated with these agents. Although the incidence of thrombocytopenia has been well described [1, 2, 3, 4], the long-term clinical sequelae of glycoprotein IIb/IIIa inhibitor-associated thrombocytopenia have not been previously reported. We sought to evaluate the incidence and outcomes of IIb/IIIa inhibitor-associated thrombocytopenia in an unselected series of patients undergoing percutaneous coronary intervention.…”

Prospective testing for drug-dependent antibodies reduces the incidence of thrombocytopenia observed with the small molecule glycoprotein IIb/IIIa antagonist roxifiban: implications for the etiology of thrombocytopenia

“…1,2 In the case of approved intravenous agents, this side effect has been observed with a frequency of up to 5.6%. [1][2][3][4][5][6][7][8][9] In addition, a number of oral GP IIb/IIIa antagonists have undergone clinical testing, and treatment, for example, with RPR 109891 was associated with a thrombocytopenia frequency of up to 13%. 10 Lower frequencies have been observed for the other oral agents in clinical development.…”

“…1,2 Retrospective studies in humans and preclinical animal models implicated drug-dependent antibodies (DDABs) to GP IIb/IIIa in the etiology of thrombocytopenia. For example, a chimpanzee presented with acute thrombocytopenia upon treatment with GP IIb/IIIa antagonists.…”