Severe Hypoxemia Caused by High-Output Heart Failure and Pulmonary Arteriovenous Malformations in Hereditary Hemorrhagic Telangiectasia.

A man affected by hereditary hemorrhagic telangiectasia who had chronic severe hypoxemia is presented. This hypoxemia was synergistically caused by high-output heart failure due to severe hepatic shunts and multiple pulmonary arteriovenous shunts. The symptomatic combination is rare, and genetic testing showed a novel endoglin mutation. (Level of Difficulty: Advanced.).