The new class of antiplatelet drugs, the GPIIb/IIIa inhibitors, has proven
to be effective in acute coronary syndromes including unstable angina and m
yocardial infarction as well as adjunct therapy for coronary interventions
for preventing morbidity and mortality. As these drugs inhibit the final co
mmon pathway of platelet activation, effectively blocking the platelet aggr
egation response, potential bleeding is a concern with their use. The risk
of bleeding has been demonstrated to be higher in patients treated with com
bination drug therapy (heparin, aspirin, thienopyridines, thrombolytics, or
al anticoagulants), when antithrombotic drugs are not given on an individua
l weight basis and with late removal of vascular access sheaths. The early
clinical trials have defined modifications in patient management that have
effectively reduced bleeding. Pooled data from the more recent clinical tri
als, mostly in coronary intervention enrolling over 27,000 patients, show a
bleeding rate of 3.6% in the drug group and 2.3% in the placebo group. Alt
hough this is acceptable, several unresolved issues remain to be addressed
regarding the GPIIb/IIIa inhibitors. Thrombocytopenia occurs infrequently w
ith all GPIIb/IIIa inhibitors but can be severe. The use of these drugs by
oral administration presents new challenges with determining optimal dosing
, drug-drug interactions and long-term effects. Incorporating point-of-care
monitoring may enable better titration of these drugs to avoid bleeding co
mplications. GPIIb/IIIa inhibitors are destined to become a mainstay therap
y for cardiovascular treatment and over time these issues should be resolve
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