title: Evaluation of von Willebrand factor with a fully magnetically levitated centrifugal continuous-flow left ventricular assist device in advanced heart failure.
abstract: Contemporary continuous-flow left ventricular assist devices (CF-LVADs) are associated with degradation of von Willebrand factor (vWF) high-molecular-weight multimers (HMWMs), a critical factor supporting platelet function. We hypothesized that the HeartMate 3 fully magnetically levitated LVAD, designed to reduce circulatory shear stress, favorably influences these hemostatic parameters.
  
  
  
  Fifteen consecutive HeartMate 3 LVAD patients were compared with 11 consecutive HeartMate II controls. Serial plasma samples were collected pre-implant and on Days 2, 7, 30 and 45 post-operatively. Changes in vWF HMWMs were evaluated by 2 independent, study-blind hematologists and confirmed using densitometry-based computerized software. Ristocetin cofactor (RiCO) and vWF antigen (vWF Ag) were measured using standard protocols with enzyme-linked immunosorbent assay.
  
  
  
  HeartMate 3 patients and HeartMate II controls had a mean age of 67.3 ± 1.4 and 52.8 ± 2.5 years, respectively (INTERMACS Profiles 2 to 4 in 93.3% and 91%, respectively). HeartMate 3 group demonstrated a significantly greater preservation of HMWMs compared with the HeartMate II group, with the most prominent decrease occurring by Day 2 post-operatively and sustained through 45 days (71.94% vs 31.16%, p = 0.001). Laboratory values (normalized to baseline) for RiCO activity, vWF Ag and RiCO:vWF Ag ratio remained in the functional range with no statistically significant differences observed between groups.
  
  
  
  The HeartMate 3 LVAD is associated with enhanced hemocompatibility compared with the HeartMate II LVAD, as demonstrated by the improved preservation of vWF HMWMs, In contrast, effects on HMWM degradation appeared to be dissociated from functional attributes. Further confirmation of these findings in randomized clinical trials is warranted.
authors.affiliation: Department of Cardiac Surgery, Institute for Clinical and Experimental Medicine, Prague, Czech Republic; Second Department of Surgery, First Faculty of Medicine, Charles University of Prague, Prague, Czech Republic. Electronic address: ivan.netuka@ikem.cz.
authors.forename: Ivan
authors.initials: I
authors.lastname: Netuka
authors.affiliation: Thrombotic Centre and Central Hematology Laboratory, Institute of Medical Biochemistry and Laboratory Diagnostics of the General University Hospital and First Faculty of Medicine of Charles University of Prague, Prague, Czech Republic.
authors.forename: Tomáš
authors.initials: T
authors.lastname: Kvasnička
authors.affiliation: Thrombotic Centre and Central Hematology Laboratory, Institute of Medical Biochemistry and Laboratory Diagnostics of the General University Hospital and First Faculty of Medicine of Charles University of Prague, Prague, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Kvasnička
authors.affiliation: NRL for Hemostasis, Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Hrachovinová
authors.affiliation: Department of Cardiac Surgery, Institute for Clinical and Experimental Medicine, Prague, Czech Republic; Third Faculty of Medicine, Charles University of Prague,Prague, Czech Republic.
authors.forename: Peter
authors.initials: P
authors.lastname: Ivák
authors.affiliation: NRL for Hemostasis, Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
authors.forename: František
authors.initials: F
authors.lastname: Mareček
authors.affiliation: Thrombotic Centre and Central Hematology Laboratory, Institute of Medical Biochemistry and Laboratory Diagnostics of the General University Hospital and First Faculty of Medicine of Charles University of Prague, Prague, Czech Republic.
authors.forename: Jana
authors.initials: J
authors.lastname: Bílková
authors.affiliation: Thrombotic Centre and Central Hematology Laboratory, Institute of Medical Biochemistry and Laboratory Diagnostics of the General University Hospital and First Faculty of Medicine of Charles University of Prague, Prague, Czech Republic.
authors.forename: Ivana
authors.initials: I
authors.lastname: Malíková
authors.affiliation: Laboratory Methods, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
authors.forename: Michaela
authors.initials: M
authors.lastname: Jančová
authors.affiliation: Department of Cardiac Surgery, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
authors.forename: Jiří
authors.initials: J
authors.lastname: Malý
authors.affiliation: St. Jude Medical, Minneapolis, Minnesota, USA.
authors.forename: Poornima
authors.initials: P
authors.lastname: Sood
authors.affiliation: St. Jude Medical, Minneapolis, Minnesota, USA.
authors.forename: Kartik S
authors.initials: KS
authors.lastname: Sundareswaran
authors.affiliation: Department of Hematology, Brigham and Women's Hospital, Boston, Massachusetts, USA.
authors.forename: Jean M
authors.initials: JM
authors.lastname: Connors
authors.affiliation: Heart and Vascular Center, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Mandeep R
authors.initials: MR
authors.lastname: Mehra
mesh_terms: D004797:Enzyme-Linked Immunosorbent Assay; D006333:Heart Failure; D006353:Heart-Assist Devices; D006801:Humans; D008875:Middle Aged; D013314:Stress, Mechanical; D014842:von Willebrand Diseases; D014841:von Willebrand Factor
chemical_list: D014841:von Willebrand Factor
keywords: hemocompatibility; hemolysis; left ventricular assist device; magnetic levitation; multimers; shear stress; von Willebrand syndrome