Tinzaparin: new indication. Easier treatment of less severe pulmonary embolism

(1) The standard first-line antithrombotic treatment for pulmonary embolism in patients without cardiovascular shock or marked hypotension is intravenous infusion of unfractionated heparin for a few days, followed by several months of oral anticoagulation. (2) In France, tinzaparin is the first low-molecular-weight heparin (LMWH) to be licensed specifically for treating pulmonary embolism (one subcutaneous injection daily). (3) The clinical file mainly comprises data from a comparative unblinded trial versus unfractionated heparin in 612 patients, which shows tinzaparin to have no advantage in terms of overall mortality or the incidence of bleeding. A trial comparing unfractionated heparin with another LMWH, reviparin, gave similar results. (4) In practice, tinzaparin offers the advantage over unfractionated heparin of not requiring intravenous administration. For the least severely ill patients, tinzaparin is an advance. Close laboratory monitoring of clotting factors is warranted for elderly and obese patients, and those with renal impairment. For other patients, intravenous infusion of unfractionated heparin remains the standard treatment for pulmonary embolism.