Cardiopulmonary exercise testing CPET

Alterations in cardiopulmonary exercise tests (CPET) have been noted in 28% to 47% of patients with sarcoidosis (6,63,65,66). Typical findings include ventilatory limitation or increased dead space/tidal volume ratio (Vd/Vx) or widened alveolar-arterial O2 (A-a O2) gradient with exercise (63,65). CPET may be abnormal when static PFTs are normal (63,67). Exercise-induced desaturation correlated with reductions in DLco (63,68-70), whereas lung volumes and expiratory flow rates did not (70). 

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