Low-molecular-weight heparin (LMWH) in the treatment of thrombosis.

Thromboembolic complications are a common and costly medical problem, associated with significant morbidity and mortality, especially in postoperative patients. There have been reports of death due to thromboembolic complications even after short procedures, e.g. arthroscopy. Low-molecular-weight heparins (LMWHs) (e.g., certoparin, dalteparin, enoxaparin, nadroparin, reviparin, tinzaparin) have been tested for treatment of deep vein thrombosis in comparison to unfractionated heparin (UFH) in many patients being effective and safe alternative for treatment of deep vein thrombosis (DVT) and venous thromboembolism (VTE). Fixed-dose subcutaneous LMWH once daily is in most cases of equivalent efficacy and safety compared to conventional UFH therapy. There may be less risk for bleeding, less platelet activation together with a control of markers of haemostatic system activation, and either no progression or regression of thrombus size in patients treated with LMWH. The handling of LMWH is more comfortable for patients and less time consuming for nurses and laboratories compared to UFH. The cost-effectiveness analysis showed that LMWH are more cost effective than UFH. It has been calculated that outpatient treatment with LMWH may save 1641 dollars per patient in comparison to hospital treatment. This economic benefit of outpatient treatment of DVT seems to be realized in different health systems. Women with antiphospholipid antibodies and a history of either prior thrombotic events or pregnancy loss are at high risk during pregnancy for either another fetal death or thrombosis and may benefit from treatment with LMWH. In patients with malignant tumors secondary prophylaxis or long-term treatment with LMWH is successful. Patients with a contraindication for oral anticoagulants may benefit from treatment with LMWH as do patients on chronic anticoagulation treatment scheduled for an operative intervention. In most instances LMWH (dalteparin, enoxaparin, nadroparin) treatment for DVT may be given once daily at a fixed dose without any harm, based on a prolonged antithrombin activity. Effectiveness and safety of LMWH (dalteparin, enoxaparin, nadroparin, tinzaparin) in comparison to UFH treatment on outpatient basis has been demonstrated in several studies. In summary, LMWHs have an established role in the treatment of DVT and pulmonary embolism (PE), on an in- and outpatient basis and could realize substantial savings. Most studies were performed with dalteparin, enoxaparin and nadroparin. There is evidence that LMWHs may help to prolong survival in cancer patients and to avoid complications of the acute coronary syndrome.