[Antithrombotic therapy in the acute phase of unstable angina]

Low molecular weight heparins appear to be a better choice in patients with unstable angina than unfractionated heparin. In addition, the excellent predictable dose-response makes them suitable to prevent ischemic complications of percutaneous coronary intervention. Although direct comparisons between LMWH and UH are limited, substantial evidence exists that patients receiving LMWH can be safely brought to cardiac catheterization. Therefore, previous concern regarding transitioning such therapy from the medical service to the cardiac catheterization laboratory should not impede the upstream use of thèse agents. Although UH remains an option in conjunction with GP IIB/IIIa inhibitors, there is substantial evidence that LMWH and GP IIb/IIIa inhibitor therapy can be used safely in combination. Although GP IIb/IIIa inhibitors are very potent to prevent ischemic events after percutaneous coronary interventions, their benefit in the medical management of unstable angina is much more modest. ADP receptor antagonists reduce major ischemic events in combination with aspirin in the medical management of unstable angina patients but also when PCI is planned. Their combination with GP IIB/IIIa receptor antagonist does not impair the benefit of GP IIb/IIIa antagonists. The development of biologic tools to monitor these antithrombotic regimen is highly warranted especially in high risk patients (chronic renal failure, elderly).