Abstract
The management of deep venous thrombosis (DVT) requires an initial treatment with
unfractionated (UF) or low-molecular-weight (LMW) heparin followed by oral anticoagulants
(OA) for at least 3 months. OA therapy, however, requires laboratory monitoring and
is associated with a definite bleeding risk. Therefore, alternative treatments such
as UF or LMW heparin have been evaluated. In a study by Monreal et al in patients
with DVT and contraindications to OA, dalteparin (5000 anti-Xa U b.i.d.) was equivalent
to UF heparin (10,000 IU b.i.d.) and was associated with fewer vertebral fractures.
In a study by Pini et al, Enoxaparin (4000 anti-Xa U once daily) was evaluated against
OA and showed similar efficacy with fewer bleeding complications in the 3-month treatment
period.
A number of studies have recently shown that the risk for late thrombotic recurrences
for patients developing postoperative DVT or associated with other transient risk
factors is much lower than in patients with idiopathic DVT or associated with a persistent
risk factor, suggesting that for the formers, 4 to 6 weeks of OA therapy may be sufficient.
LMW heparins appear to be a promising alternative therapy for these patients, because
in the first month of OA administration the risk for bleeding is higher and the need
of laboratory monitoring more stringent. This should be evaluated in appropriate clinical
trials.
Keywords:
Deep venous thrombosis - heparin - low-molecular-weight (LMW) heparin - oral anticoagulants
- bleeding
