AVWS in ECMO

Q: What percentage of Extracorporeal Membrane Oxygenation (ECMO) patients develop Acquired von Willebrand syndrome (AVWS)? - select one

A) 10%

B) 25%

C) 50%

D) 75%

E) 100%

Answer: E

To date, the literature indicates that the incidence of AVWS is 100% among ECMO patients and that it typically develops within 24 hours of ECMO initiation. Fortunately, it resolves once the ECMO is decannulated. 

The contributory components are the coagulopathic effect of extracorporeal circulation, anticoagulation required for ECMO, thrombocytopathy, and, most importantly, the shear stress induced by continuous-flow via ECMO cannulae. Shear stress may damage VWF, and increased binding to platelets may enhance ADAMTS13-mediated proteolysis.

#hematology

#ECMO

References:

1. Frere C, Mazzeffi M, Maier CL, et al. Acquired von Willebrand syndrome during extracorporeal membrane oxygenation support: a comprehensive review of current evidence: communication from the ISTH SSC on perioperative and critical care thrombosis and hemostasis. J Thromb Haemost 2024; 22:2608.

2. Kalbhenn J, Schmidt R, Nakamura L, et al. Early diagnosis of acquired von Willebrand Syndrome (AVWS) is elementary for clinical practice in patients treated with ECMO therapy. J Atheroscler Thromb 2015; 22:265.