A case of hypertrophic obstructive cardiomyopathy and acquired von Willebrand syndrome: response to medical therapy.

Heyde's syndrome is the combined occurrence of acquired von Willebrand disease caused by aortic valve stenosis and gastrointestinal bleeding that occurs particularly in elderly patients. The bleeding may be linked to the intravascular shear-induced proteolysis of high-molecular-weight multimers (HMWMs) of von Willebrand factor (vWF). Hypertrophic obstructive cardiomyopathy (HOCM) in the left ventricular outflow tract generates a high shear stress condition that can induce such proteolysis. We report the case of a 70-year-old woman with HOCM who had severe anemia and loss of HMWMs. After reduction of the outflow gradient by medical treatment, vWF normalized, and her anemia alleviated.