[Review and future perspectives on low-molecular-weight heparin]

Low molecular weight heparins appear to be a better choice in patients with unstable angina than unfractionated heparin. Their favourable pharmacokinetic profile allows an excellent predictable dose-response with a subsequent rapidly effective and stable anticoagulation, which is ideal in the setting 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 these agents. Direct i.v. injection of LMWH in the setting of elective PCI have also been shown to be safe and effective. 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. Patients with either chronic renal failure, mechanical valves or atrial fibrillation are other important issues which deserve additional prospective evaluation of the safety and the efficacy of LMWH. Development of a biological assay for monitoring either LMWH or GP IIb/IIIa receptor antagonists is another important issue in the setting of antithrombotic combinations which are now commonplace.