Tirofiban and emergency coronary surgery

Abstract

The final common pathway of platelet aggregation leading to coronary thrombosis involves cross-linking of platelet receptor glycoprotein IIb-IIIa by primarily fibrinogen. Glycoprotein IIb-IIIa antagonists are being increasingly used as adjunctive therapy during percutaneous coronary intevention, and have shown to reduce the risk of death and myocardial infarction. However, a proportion of these patients continue to remain ischemic and present for emergency coronary grafting. The profound platelet inhibition in these patients enhances the already heightened risk of post-operative bleeding. With the recent approval of tirofiban for patients with acute coronary syndromes, the number of patients receiving tirofiban who subsequently undergo coronary artery bypass grafting is expected to increase substantially. Little clinical data exist, on patients who require immediate coronary artery grafting after receiving tirofiban. This article reviews the evidence for bleeding following tirofiban, discusses the relevant mechanism of action and pharmacodynamics, and analyses the strategies available in patients who need emergency coronary artery grafting after tirofiban.

CABG-procedures in patients with pretreatment with the GPIIb/IIIa-receptor antagonist tirofiban (Aggrastat©): Modification of perioperative management?

“…Another Canadian working group suggested that both eptifibatide and tirofiban have no increased risks for bleeding in comparison to abciximab in cases of urgent or emergent coronary surgery [11]. In contrast to our current findings Genoni and colleagues could not prove the benefit of stopping tirofiban therapy eight ours prior to surgery [12]. Of course, the risk for transfusion depends on several other factors, such as preoperative anemia, severely reduced left ventricular function or age, as already reported by the group around Litmathe [13].…”

Emergency coronary artery bypass grafting in patients with acute myocardial infarction treated with glycoprotein IIb/IIIa receptor inhibitors

“…The authors hypothesize that platelet quiescence achieved with this shortacting drug could result in preserved platelet number and function, with improvement in hard clinical endpoints, without increasing bleeding rates. Similarly, reviewing the limited data on tirofiban and emergency coronary surgery, Shanmugam concludes that urgent revascularization can be safely performed in patients within a few hours of discontinuation of tirofiban with little added risk [32].…”

Antiplatelet Therapy in Cardiovascular Disease – Past, Present and Future

“…It has a rapid onset and short duration of action after proper intravenous administration. Platelet activity returns to normal 4 to 8 hours after the drug is withdrawn (19). Eptifibatide (Integrilin) is the newer anti-platelet drug which inhibits the glycoprotein IIb/IIIa inhibitor.…”