Comparison of Safety of Subcutaneous Enoxaparin as Outpatient Anticoagulation Bridging Therapy in Patients With a Mechanical Heart Valve Versus Patients With Nonvalvular Atrial Fibrillation

Published:September 28, 2009DOI:
      Patients with mechanical heart valves (MHVs) are at a higher risk for thromboembolic events than patients with atrial fibrillation (AF). This difference is observed in the higher maintenance international normalized ratio (INR) range for patients with MHV and in the selection for anticoagulation bridge therapy when warfarin is interrupted perioperatively. However, once the decision is made to “bridge,” the same therapeutic options, unfractionated heparin and subcutaneous low-molecular-weight heparin (LMWH), are applicable to the 2 patient populations. Unfractionated heparin requires extended hospitalization and is often not selected. A paucity of published data exist establishing the efficacy and safety of LMWH as a bridging agent. The aim of this study was to describe a single-center experience and to provide data supporting the use of enoxaparin as a bridging agent. The study assessed whether patients with MHV undergoing bridging for a variety of procedures had higher thromboembolic and hemorrhagic risk compared to patients with nonvalvular AF. We performed a retrospective cohort study of 173 patients (with MHV and AF) who underwent 230 bridging episodes with an LMWH, enoxaparin, from February 2002 through September 2007. Main outcome measurements were the incidence of thromboembolic and hemorrhagic events within 2 months after the procedure. Of total bridging episodes, 130 episodes met the inclusion criteria; 62 episodes occurred in the MHV population and 68 episodes occurred in the AF population. The procedures varied from minor invasive procedures to major surgeries. There were no deaths or thromboembolic events. Major and minor bleeding rates were similar between the MHV and AF groups (3.2% and 2.9%, 14.5% and 13.2% respectively, p = NS). The major bleeding rate was similar to published data on bridging therapy. Most bleeding episodes (73%) occurred within 7 days after the procedure. In conclusion, our study provided actual outpatient anticoagulation clinical data on using LMWH as an option for periprocedural bridging anticoagulation in patients with MHV.
      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to American Journal of Cardiology
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Ansell J.
        • Hirsh J.
        • Poller L.
        • Bussey H.
        • Jacobson A.
        • Hylek E.
        The pharmacology and management of the vitamin K antagonists.
        Chest. 2004; 126: 204S-233S
        • Fuster V.
        ACC/AHA/ESC 2006 guidelines for the management of atrial fibrillation.
        J Am Coll Cardiol. 2006; 48: e149-e246
        • Singer D.E.
        • Albers G.W.
        • Dalen J.E.
        • Fang M.C.
        • Go A.S.
        • Halperin J.L.
        • Lip G.Y.H.
        • Manning W.J.
        Antithrombotic therapy in atrial fibrillation.
        Chest. 2008; 133: 546S-592S
        • Singer D.E.
        • Albers G.W.
        • Dalen J.E.
        • Go A.S.
        • Halperin J.L.
        • Manning W.J.
        Antithrombotic therapy in atrial fibrillation: the seventh ACCP conference on antithrombotic and thrombolytic therapy.
        Chest. 2004; 126: 429S-456S
        • Schulman S.
        • Kearon C.
        Definition of major bleeding in clinical investigations of antihemostatic medicinal products in non-surgical patients.
        J Thromb Haemost. 2005; 3: 692-694
        • Ferreira I.
        • Dos L.
        • Tornos P.
        • Nicolau I.
        • Permanyer-Miralda G.
        • Soler-Soler J.
        Experience with enoxaparin in patients with mechanical heart valves who must withhold acenocoumarol.
        Heart. 2003; 89: 527-530
        • Kovacs M.J.
        • Kearon C.
        • Rodger M.
        • Anderson D.R.
        • Turpie A.G.G.
        • Bates S.M.
        • Desjardins L.
        • Douketis J.
        • Kahn S.R.
        • Solymoss S.
        • Wells P.S.
        Single-arm study of bridging therapy with low-molecular-weight heparin for patients at risk of arterial embolism who require temporary interruption of warfarin.
        Circulation. 2004; 110: 1658-1663
        • Douketis J.D.
        • Johnson J.
        • Turpie A.B.
        Low-molecular-weight heparin as bridging anticoagulation during interruption of warfarin.
        Arch Intern Med. 2004; 164: 1319-1326
        • Jaffer A.K.
        • Ahmed M.
        • Brotman D.J.
        • Bragg L.
        • Seshadri N.
        • Qadeer M.A.
        • Klein A.
        Low-molecular-weight-heparin as periprocedural anticoagulation for patients on long-term warfarin therapy: a standardized bridging therapy protocol.
        J Thromb Thrombolysis. 2005; 20: 11-16
        • Halbritter K.M.
        • Wawer H.A.
        • Beyer J.
        • Oettler W.
        • Schellong M.
        Bridging anticoagulation for patients on long-term vitamin-K-antagonists.
        J Thromb Haemost. 2005; 3: 2823-2825
        • Spyropoulos A.C.
        • Turpie A.G.G.
        • Dunn A.S.
        • Spandorfer J.
        • Douketis J.
        • Jacobson A.
        • Frost F.J.
        Clinical outcomes with unfractionated heparin or low-molecular-weight heparin as bridging therapy in patients on long-term oral anticoagulants: the REGIMEN registry.
        J Thromb Haemost. 2006; 4: 1246-1252
        • Spyropoulos A.C.
        • Frost F.J.
        • Hurley J.S.
        • Robert M.
        Costs and clinical outcomes associated with low-molecular-weight heparin vs unfractionated heparin for perioperative bridging in patients receiving long-term oral anticoagulant therapy.
        Chest. 2004; 125: 1642-1650
        • Salem D.N.
        • Stein P.D.
        • Al-Ahmad A.
        • Bussey H.I.
        • Horstkotte D.
        • Miller N.
        • Pauker S.G.
        Antithrombotic therapy in valvular heart disease—native and prosthetic: the seventh ACCP conference on antithrombotic and thrombolytic therapy.
        Chest. 2004; 126: 457S-482S
        • Douketis J.D.
        • Berger P.B.
        • Dunn A.S.
        • Jaffer A.K.
        • Spyropoulos A.C.
        • Becker R.C.
        • Ansell J.
        The perioperative management of antithrombotic therapy.
        Chest. 2008; 133: 299S-339S
        • Carrel T.P.
        • Klingenmann W.
        • Mohacsi P.J.
        • Berdat P.
        • Althaus U.
        Perioperative bleeding and thromboembolic risk during non-cardiac surgery in patients with mechanical prosthetic heart valves: an institutional review.
        J Heart Valve Dis. 1999; 8: 392-398
      1. Butchart E.G. Bodnar E. Thrombosis, Embolism and Bleeding. ICR Publishers, London1992: 293-331

      Linked Article