1 INTRODUCTION People with a severe von Willebrand disease (VWD) bleeding phenotype experience frequent, prolonged and excessive mucocutaneous bleeding, such as epistaxis, gingival or gastrointestinal (GI) bleeding, heavy menstrual bleeding, postoperative bleeds and hemarthroses, that has a significant effect on their quality of life.1-6 Unfortunately, successful treatment of GI bleeding has remained particularly difficult and elusive, potentially due to arteriovenous malformations (AVMs) in...