Successful bosentan therapy for pulmonary arterial hypertension associated with hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is a hereditary vascular disease with multiple arterial venous malformations. Pulmonary arterial hypertension is occasionally associated with HHT; however, there is no evidence of targeted therapy for this subgroup of patients. This report describes a 37-year-old woman who presented with dyspnea on exertion. She was finally diagnosed with pulmonary arterial hypertension associated with HHT (HHT2, MIM 600376), and had multiple arterial venous malformations in the lung, liver and pancreas. An oral dual endothelin receptor (ET_A/ET_B) antagonist, bosentan, was prescribed, and her symptoms, exercise capacity and laboratory findings imporved greatly after treatment. Pulmonary arterial pressure also decreased. Endothelin receptor antagonist is a possible treatment option for pulmonary arterial hypertension associated with HHT.