title: Dabigatran etexilate as second-line therapy in patients with a left ventricular assist device.
abstract: BACKGROUND
  Administration of anticoagulation is mandatory in patients with left ventricular assist devices (LVADs). Vitamin K antagonists require regular monitoring and dosage adjustment. Dabigatran administered in a standard dose twice daily is more convenient and achieves a stable anticoagulant effect, but its effectiveness and safety in patients with LVADs has not been investigated. The objective of the present study was to evaluate whether dabigatran can be used safely as a second-line anticoagulation option in patients with a HeartMate II (HMII) LVAD.
  
  
  METHODS
  The study population consisted of 7 consecutive patients with end-stage heart failure who underwent HMII implantation and sequentially received acenocoumarol and dabigatran. Occurrence of stroke, systematic embolism, device thrombosis and major or life-threatening bleeding were included in the analysis. An acute decrease in plasma hemoglobin >2 g/dL or a need for transfusion of at least 2 units of packed red blood cells (PRBC) was defined as major bleeding, while an acute decrease in plasma hemoglobin >5 g/dL, fatal, symptomatic intracranial bleed, need for transfusion of at least 4 units PRBC, or association with hypotension requiring the use of intravenous inotropic agents or surgical intervention was defined as life-threatening bleeding.
  
  
  RESULTS
  The duration of follow up was 1564 ± 292 days. Patients received acenocoumarol for 855 ± 246 days, followed by dabigatran for 708 ± 368 days. The rates of thromboembolic events were similar under dabigatran and acenocoumarol treatment: strokes, 0.094 vs. 0 /patient-year, p=0.36; systemic embolism, no event in either group; and device thrombosis, 0.053 vs. 0.258 events/patient-year, p=0.19, respectively. Compared to an adjusted acenocoumarol dose, the standard dabigatran dose resulted in similar rates of life-threatening bleeding, but significantly lower rates of major bleeding (0.18 vs. 0.27 bleeds/patient-years, p=0.76, and 0.047 vs. 0.547, p<0.001, for dabigatran and acenocoumarol, respectively).
  
  
  CONCLUSIONS
  The safe and effective use of dabigatran as a second-line anticoagulation therapy in patients with HMII seems feasible. However, these data must be confirmed in a randomized study.
authors.affiliation: Third Department of Cardiology, University of Athens Medical School, Athens, Greece.
authors.forename: John V
authors.initials: JV
authors.lastname: Terrovitis
authors.forename: Argyrios
authors.initials: A
authors.lastname: Ntalianis
authors.forename: Chris J
authors.initials: CJ
authors.lastname: Kapelios
authors.forename: Styliani
authors.initials: S
authors.lastname: Vakrou
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Diakos
authors.forename: Lambros
authors.initials: L
authors.lastname: Katsaros
authors.forename: Michalis
authors.initials: M
authors.lastname: Tsamatsoulis
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Kaldara
authors.forename: Christos
authors.initials: C
authors.lastname: Charitos
authors.forename: John N
authors.initials: JN
authors.lastname: Nanas
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects; D000069604:Dabigatran / Q000008:administration & dosage / Q000009:adverse effects; D005260:Female; D005500:Follow-Up Studies; D006115:Greece / Q000453:epidemiology; D006333:Heart Failure / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D006353:Heart-Assist Devices / Q000009:adverse effects / Q000706:statistics & numerical data; D006470:Hemorrhage / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011183:Postoperative Complications / Q000453:epidemiology / Q000517:prevention & control; D012720:Severity of Illness Index; D013923:Thromboembolism / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D018487:Ventricular Dysfunction, Left / Q000209:etiology / Q000628:therapy*
chemical_list: D000925:Anticoagulants; D000069604:Dabigatran