VWF and acquired von willebrand syndrome: To minimise this risk, device surfaces are heparinised, and use of systemic antithrombotic drugs is mandatory.5 On the other hand, patients are also at risk of bleeding which may be aggravated by use of anticoagulant and antiplatelet treatment.6 The shear force of the rotary pump facilitates cleavage of von Willebrand factor (VWF) multimers by ADAMTS-13 with loss of function and an acquired von Willebrand syndrome (AVWS).7,8 Similar to patients with von Willebrand disease, bleeding complications such as epistaxis and gastrointestinal bleeds are frequent in patients supported with LVAD.