Innovance vwf ac system

Von Willebrand Factor activity, von Willebrand Factor antigen and factor VIII were measured at baseline and after 4 weeks and results at both points of time were available in 85 patients. Von Willebrand Factor activity was analyzed using the INNOVANCE® VWF Ac system provided by SIEMENS (Siemens Healthcare GmbH, Erlangen/Germany), and von Willebrand Factor antigen was measured by immunoturbidimetry using the measuring devices of Siemens Healthcare Diagnostics or SYSMEX (SYSMEX CORPORATION). The results of factor VIII were gained by in‐vitro diagnostics of coagulation factor VIII deficient plasma by SIEMENS (Siemens Healthcare GmbH, Erlangen/Germany).

vWF activity (vWF:Ac), vWF antigen (vWF:Ag) and activity-to-antigen-ratio (vWF:Ac/Ag ratio) were assessed at baseline before TAVI and 6 h and 24 h after TAVI. vWF:Ac was analyzed using the Innovance^® vWF Ac system provided by SIEMENS (Siemens Healthcare GmbH, Erlangen/Germany), and vWF:Ag was measured by immunoturbidimetry using the measuring devices of Siemens Healthcare Diagnostics or Sysmex (Sysmex Corporation). AVWS was defined as vWF:Ac/Ag ratio ≤ 0.7 [16 (link)]. vWF:Ag and vWF:Ac levels above measurable range were determined as the highest measurable value, each at 600 U/dl.