A young male patient reported for evaluation of progressive easy fatigability, accompanied by a recent history of recurrent haemoptysis. His clinical examination was unremarkable except for evidence of pulmonary arterial hypertension (PAH). Routine investigations (haemogram, coagulogram, serological tests for connective tissue disorders and a sputum Ziehl Neelsen stain for acid-fast bacilli) were normal. Two-dimensional echocardiography suggested PAH (pulmonary artery systolic pressure-67 mm Hg), whereas the 64-slice spiral CT pulmonary angiogram showed a dilated main pulmonary artery along with bilateral arteriovenous malformations. Cardiac catheterisation performed subsequently confirmed the presence of PAH. On the basis of the above findings, a diagnosis of hereditary haemorrhagic telangiectasia (HHT) complicated with PAH was made, and the patient was started on oral sildenafil therapy to which he responded well. This rare complication of HHT, which requires a high degree of suspicion for diagnosis, is discussed.