OWR is a genetic disease, transmitted as an autosomal dominant disorder characterized by arteriovenous malformations predominantly involving the mucocutaneous epithelium. One of the significant complications is the development of arteriovenous fistulas in different organs like the liver and brain. One of the rarest complications of this arteriovenous conduit is a high-output heart failure. We would like to describe a 66 years old woman who was admitted with a high-output cardiac failure who deteriorated clinically and was treated successfully by conservative management.