title: Enoxaparin monotherapy without oral anticoagulation to treat acute symptomatic pulmonary embolism.
abstract: Conventional anticoagulation for symptomatic pulmonary embolism consists of continuous intravenous unfractionated heparin as a "bridge" to oral anticoagulation. This strategy requires 5 days or more of intravenous heparin while oral vitamin K antagonists gradually achieve a therapeutic effect. Oral vitamin K antagonists require frequent blood testing to optimize dosing, and their interactions with other medications and foods make regulation difficult. Therefore we tested a different approach to therapy: long-term enoxaparin monotherapy. We randomized 60 symptomatic pulmonary embolism patients in a 2:1 ratio to 90 days of enoxaparin as monotherapy without warfarin (N=40) or to intravenous unfractionated heparin as a "bridge" to warfarin, target INR 2.0-3.0 (N=20). Enoxaparin patients received 1 mg/kg twice daily for 14 days during the acute phase followed by randomized assignment during the chronic phase to 1.0 mg/kg vs. 1.5 mg/kg once daily. In an intention-to-treat analysis, 3 of the 40 enoxaparin patients developed recurrent venous thromboembolism compared with 0 of 20 standard therapy patients (p = 0.54). One of the 40 enoxaparin patients had a major hemorrhagic complication compared with 2 of the 20 standard therapy patients (p = 0.26). Median hospital length of stay was shorter with enoxaparin compared to standard therapy (4 vs. 6 days) (p = 0.001). Following our study we can conclude that extended 3-month treatment with enoxaparin as monotherapy for symptomatic, acute pulmonary embolism is feasible and warrants further study in a large clinical trial.
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA. sgoldhaber@partners.org
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Beckman
authors.forename: Kelly
authors.initials: K
authors.lastname: Dunn
authors.forename: Arthur A
authors.initials: AA
authors.lastname: Sasahara
authors.forename: Samuel Z
authors.initials: SZ
authors.lastname: Goldhaber
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D017984:Enoxaparin / Q000008:administration & dosage* / Q000633:toxicity; D005240:Feasibility Studies; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced; D006493:Heparin / Q000008:administration & dosage; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D011655:Pulmonary Embolism / Q000150:complications / Q000188:drug therapy*; D055502:Secondary Prevention; D020246:Venous Thrombosis / Q000517:prevention & control; D018497:Ventricular Dysfunction, Right / Q000139:chemically induced
chemical_list: D017984:Enoxaparin; D006493:Heparin