title: Anticoagulant bridging in left-sided mechanical heart valve patients.
abstract: BACKGROUND
  In preparation for an invasive procedure with a high bleeding risk, patients with a mechanical heart valve temporarily have to discontinue their anticoagulant therapy and are usually bridged with either intravenous unfractionated heparin (UFH) or subcutaneous low-molecular-weight heparin (LMWH). In this study we retrospectively analyzed the safety of UFH versus LMWH as bridging strategy in left-sided mechanical heart valve patients.
  
  
  METHODS
  We performed a retrospective multicenter study in four surgical centers in The Netherlands. Patients with a mechanical heart valve implantation bridged from January 2010 until January 2015 were included. The cumulative incidence of adverse events in the 30days following the procedure was recorded. Main outcomes were major bleeding according to International Society on Thrombosis and Haemostasis (ISTH) criteria, symptomatic thromboembolism, and mortality.
  
  
  RESULTS
  In total, 238 (174 aortic, 42 mitral, 22 aortic+mitral) bridging episodes were included. The incidence of major bleeding was 16 (19%) events in the UFH group versus 29 (19%) events in the LMWH group (p=0.97). Incidences of thromboembolism were 2 (2.4%) versus 1 (0.6%). The incidence of death was 1 (1.2%) patient in the UFH group versus 3 (1.9%) patients in the LMWH group. More than 50% of all bleeding complications were categorized as a major bleeding.
  
  
  CONCLUSIONS
  Bridging anticoagulation in patients with aortic and mitral mechanical valves is associated with considerable risk, but no difference was apparent between UFH and LMWH strategy. The rate of thromboembolism and death was low with either strategy and the vast majority of adverse events were bleedings.
authors.affiliation: University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: E A
authors.initials: EA
authors.lastname: Hart
authors.affiliation: University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Jansen
authors.affiliation: University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: T A
authors.initials: TA
authors.lastname: Meijs
authors.affiliation: Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: B J
authors.initials: BJ
authors.lastname: Bouma
authors.affiliation: Onze Lieve Vrouwe Gasthuis, Amsterdam, The Netherlands.
authors.forename: R K
authors.initials: RK
authors.lastname: Riezebos
authors.affiliation: Haga Ziekenhuis, The Hague, The Netherlands.
authors.forename: W
authors.initials: W
authors.lastname: Tanis
authors.affiliation: Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: W J P
authors.initials: WJ
authors.lastname: van Boven
authors.affiliation: Onze Lieve Vrouwe Gasthuis, Amsterdam, The Netherlands.
authors.forename: V
authors.initials: V
authors.lastname: Hindori
authors.affiliation: Thrombosis Center Saltro, Utrecht, The Netherlands.
authors.forename: N
authors.initials: N
authors.lastname: Wiersma
authors.affiliation: University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: T
authors.initials: T
authors.lastname: Dessing
authors.affiliation: University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Westerink
authors.affiliation: University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: s.a.j.chamuleau@umcutrecht.nl.
authors.forename: S A J
authors.initials: SA
authors.lastname: Chamuleau
mesh_terms: D000925:Anticoagulants / Q000627:therapeutic use*; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis; D006495:Heparin, Low-Molecular-Weight / Q000627:therapeutic use*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D019106:Postoperative Hemorrhage / Q000453:epidemiology*; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D013923:Thromboembolism / Q000453:epidemiology / Q000517:prevention & control*
chemical_list: D000925:Anticoagulants; D006495:Heparin, Low-Molecular-Weight
keywords: Bleeding; Bridging; Low-molecular-weight heparin; Mechanical heart valve; Thromboembolism; Unfractionated heparin