[Cardiopulmonary exercise testing and dyspnea in patients with chronic respiratory diseases].

Cardiopulmonary exercise testing (CPET) is the most comprehensive investigation for understanding the mechanisms responsible for dyspnea in patients with chronic respiratory disease. The two observations presented here illustrate how CPET can contribute to the management of patients with interstitial lung diseases. A 60-year-old woman had been followed for 20 years for non-progressive pulmonary sarcoidosis, untreated for many years. CPET led to the diagnosis of an atrial septal defect. A 76-year-old man was treated for idiopathic pulmonary fibrosis. Before pulmonary rehabilitation, CPET was performed which revealed significant aortic valve stenosis, which had been to that point asymptomatic. In these two observations, CPET determined the presence of an associated disease, distinct from the interstitial lung disease.