Hereditary hemorrhagic telangiectasia (HHT) is a genetic disorder in which there is faulty development of the arteries. There is a high incidence of pulmonary hypertension (PH) in these patients, the pathophysiology of which is not fully known. An increase in cardiac output, causing high-output cardiac failure, and increased pulmonary vascular resistance secondary to genetic mutations are the main reasons. We report a 25-year-old male with HHT who presented with right heart failure secondary to PH in whom both the above mechanisms were operating. The coexistence of giant pulmonary arteriovenous malformations with severe PH is a rare scenario influencing management decisions that are discussed. In addition, this patient highlights the classical visceral vascular malformations in this rare disorder.