Bevacizumab is now an emerging treatment option for severe hereditary hemorrhagic telangiectasia–related bleeding including epistaxis and gastrointestinal tract bleeding. The impact of long-term intravenous bevacizumab therapy on cardiac structure and function is unknown. We describe 3 patients receiving intravenous bevacizumab therapy for severe hereditary hemorrhagic telangiectasia–related bleeding who were found to have abnormal mobile masses on the mitral valve (n=2) and aortic valve (n=1). The clinical impact of these findings is unknown and requires further study.