A 44-year-old with epistaxis since adolescence, a red dot on the tongue, dyspnea, and an ejection fraction of 75-80% presents for evaluation. What is the most likely diagnosis?

• A. Pulmonary arteriovenous malformation
• B. Pulmonary embolism
• C. Primary pulmonary hypertension
• D. Mitral valve prolapse

Answer: (A)

This scenario points to hereditary hemorrhagic telangiectasia with pulmonary arteriovenous malformations. The key clues are recurrent epistaxis since adolescence and a visible mucocutaneous telangiectasia (a red dot on the tongue), which together are classic for Osler-Weber-Rendu syndrome. Pulmonary arteriovenous malformations arise with this condition and create a right-to-left shunt in the lungs, leading to dyspnea despite a normal or near-normal ejection fraction. The heart’s pumping ability is preserved, so heart failure is unlikely the cause of dyspnea here.

Pulmonary embolism would present more acutely with sudden or pleuritic chest pain and hypoxemia, not a long-standing history of epistaxis and telangiectasias. Primary pulmonary hypertension can cause dyspnea with preserved EF but lacks the mucocutaneous vascular findings. Mitral valve prolapse usually presents with palpitations or a midsystolic click and murmur, not epistaxis or telangiectasias.

So the combination of epistaxis, mucocutaneous telangiectasia, and dyspnea with preserved LV function best fits pulmonary arteriovenous malformation as part of hereditary hemorrhagic telangiectasia.