Applications of anti-platelet monitoring in catheterization laboratory.

Abstract

Platelet function tests may measure different aspects of platelet function, which include adherence, activation, aggregation and secretion. The goal of platelet function testing in the catheterization lab is to provide information about the platelet contributions to the risk of thrombotic or hemorrhagic events and optimization of anti-platelet therapy for percutaneous interventions (PCI). Important clinical questions prior to coronary interventions are whether an antiplatelet agent is having the desired effect on platelet inhibition (ef~cacy) and whether the patient has suf~cient residual platelet function to avoid bleeding (safety). The role of aspirin and thienopyridines is well established in management of coronary artery disease and in the setting of coronary interventions. The last several years have demonstrated the unequivocal ef~cacy of intravenously administered platelet GPIIb/IIIa antagonists in the management of acute coronary syndromes and in the setting of percutaneous interventions. Twenty-~ve years ago, an important insight into the molecular basis for platelet aggregation was provided by the discovery that two major membrane glycoprotein bands, GPII and GPIII were missing from the surface of thrombasthenic platelets [1]. To date, more than 60,000 patients with ischemic heart disease have been treated in clinical trials with a new class of potent and highly effective antiplatelet agents, speci~cally targeting this IIb/IIIa receptor [2]. Three such drugs have been licensed by the US Food and Drug Administration, and many more GPIIb/IIIa antagonists are in phase II and III trials for a potentially expanding series of clinical indications. Four parenterally administered GPIIb/IIIa antagonists (abciximab, epti~batide, tiro~ban and lami~ban) have been tested for two different clinical indications, percutaneous coronary interventions and acute coronary syndromes. The trials show a drug class effect, with all agents reducing ischemic events.