[Multicenter, prospective study comparing enoxaparin with unfractionated heparin in the treatment of submassive pulmonary thromboembolism].

OBJECTIVE To compare the safety and efficacy of enoxaparin and unfractionated heparin in the treatment of submassive pulmonary thromboembolism (PTE). MATERIAL AND METHODS Fifty-six patients with PTE who did not need fibrinolytic treatment were enrolled prospectively. The patients were randomly assigned to 2 treatment groups: Group A received enoxaparin (1 mg/kg every 12 hours) and Group B received adjusted doses of unfractionated heparin. The oral anticoagulant therapy was started on confirmation of the diagnosis and continued for 6 months. Incidences of recurrence of thromboembolism and of severe bleeding were assessed at the end of this period. RESULTS Six patients were withdrawn from the study. Twenty-nine of the 50 remaining patients were in Group A (enoxaparin) and 21 in Group B (unfractionated heparin). A recurrence of thromboembolism was diagnosed in 3 patients from Group A (10.7%) and 2 patients from Group B (9.5%). There were no significant differences. Two patients died, one death being attributed to bleeding secondary to the oral anticoagulant treatment (Group A) and the other to a process unrelated to PTE. CONCLUSIONS Enoxaparin seems to be as effective and safe as unfractionated heparin in the initial treatment of PTE.