Early histological changes of pulmonary arterial hypertension disclosed by invasive cardiopulmonary exercise testing.

Early diagnosis of pulmonary artery hypertension (PAH) is diagnostically challenging given the extent of pulmonary vascular remodeling required to bring about clinical signs and symptoms. Exercise testing can be invaluable in this setting, as stressing the cardiopulmonary system may unmask early disease. This report describes a young patient with a positive family history of PAH in whom contemporaneous invasive cardiopulmonary exercise testing and surgical lung biopsy reveal the novel association between exercise pulmonary hypertension (ePH) and early histological changes of PAH.