Hereditary Hemorrhagic Telangiectasia (HHT), also referred to as Osler-Weber-Rendu (OWR) after several doctors who first studied HHT, is an autosomal dominant genetic disorder of the blood vessels which affects approximately 1 in 5,000 people. It affects males and females, from all ages and racial and ethnic groups and is a hereditary disorder that is characterized by abnormal blood vessels. Blood vessels are the tubes that carry blood around our bodies. A person with HHT has a tendency to form blood vessels that lack normal capillaries between an artery and vein. This means that arterial blood under high pressure flows directly into a vein without first having to squeeze through very small capillaries. This place where an artery is connected directly to a vein tends to be a fragile site that can rupture and bleed.

 

About 95% of people with the gene for HHT will eventually develop signs or symptoms of HHT, usually by the age of 40. The most common sign is nose bleeds. Other health concerns can vary in number, complexity, and symptom range, but often include vessel malformations in the brain, liver, lungs, spinal cord, stomach and intestines. However, just because a person reaches the age of 50 without symptoms of HHT does not mean that they are not affected.

 

It is believed that 90% of those who have HHT don’t know that they have the disease.

 

These people are at great risk of experiencing a catastrophic event.