Gastrointestinal bleeding in von Willebrand disease.

Gastrointestinal bleeding due to colonic angiodysplasia is a well-recognised complication of von Willebrand disease (vWD), occurring almost exclusively in subtypes of the disease associated with a reduction in high-molecular-weight (HMW) multimers of von Willebrand factor (vWF). A deficiency of vWF HMW multimers also provides the link between aortic stenosis and gastrointestinal (GI) bleeding in Heyde's syndrome. The diagnosis and treatment of the angiodysplastic bleeding in vWD can be very difficult and the role of vWF containing concentrates in treatment and prophylaxis remains to be established.