The role of low-molecular-weight heparins in arterial diseases: optimizing antithrombotic therapy.
On the basis of current evidence, all patients with acute coronary syndromes should receive optimized medical therapy, whether or not they ultimately undergo an invasive revascularization procedure, to improve both clinical outcomes and cost effectiveness. While standard aspirin and unfractionated heparin (UFH) have improved short-term outcomes, they do not eliminate the risk of recurrent ischemic episodes. The recent introduction of platelet fibrinogen receptor antagonists and low-molecular-weight heparins (LMWHs) has offered an opportunity to develop more aggressive antithrombotic regimens. The LMWHs have been thoroughly evaluated in unstable angina and non-Q wave myocardial infarction (UA/NQMI), and have demonstrated improved efficacy compared to standard UFH, without an increase in major complications caused by bleeding. Experience has also been gathered using LMWHs in other arterial diseases (such as pregnant patients with prosthetic heart valves) and as an adjunctive therapy with thrombolytics for acute myocardial infarction. Lastly, studies are currently underway evaluating LMWHs in patients with atrial fibrillation.