Pharmacologic therapy for the management of thrombosis: Unfractionated heparin or low-molecular-weight heparin?

Use of intermittent pneumatic compression in the treatment of venous ulcers

Venous ulcers affect up to 1% of the population. This review provides the hemodynamic, hematologic and clinical effects of intermittent pneumatic compression (IPC) in the treatment of venous ulcers. It presents the different IPCs and their application on venous disease. It points out that a large randomized study on IPC versus standard four-layer compression in the treatment of venous ulcers is needed. The cost–effectiveness of IPC in the treatment of venous ulcers should also be assessed.

Covalent antithrombin-heparin complexes

Unfractionated heparin (UFH) and low molecular weight heparin (LMWH) have been utilized as primary anticoagulants for thrombosis prophylaxis and treatment. However, a number of biophysical and safety limitations have led to development of new anticoagulants. Covalent antithrombin-heparin (ATH) complexes may address many of these issues. Early ATH products were prepared that had increased intravenous half-lives relative to UFH but lacked any improvement in anti-factor Xa activity or had no catalytic activity or reactivity against thrombin. However, a recent conjugate developed by Chan et al. has displayed a number of superior properties. Chan et al. ATH has an increased direct thrombin inhibition rate and can catalyze coagulant enzyme inhibition by exogenous antithrombin with very high specific activity. Unlike UFH, clot-bound thrombin is readily inhibited by ATH and, at similar antithrombotic efficacy, the ATH has improved bleeding profiles compared to heparins. Given the preclinical findings, Chan et al. ATH may warrant clinical trial testing for control of clot propagation.