Cardiopulmonary exercise testing in interstitial lung diseases and the value of ventilatory efficiency

Abstract

Interstitial lung diseases (ILDs) are diverse parenchymal pulmonary disorders, primarily characterised by alveolar and interstitial inflammation and/or fibrosis, and sharing pathophysiological similarities. Thus, patients generally harbour common respiratory symptoms, lung function abnormalities and modified exercise adaptation. The most usual and disabling complaint is exertional dyspnoea, frequently responsible for premature exercise interruption. Cardiopulmonary exercise testing (CPET) is increasingly used for the clinical assessment of patients with ILD. This is because exercise performance or dyspnoea on exertion cannot reliably be predicted by resting pulmonary function tests. CPET, therefore, provides an accurate evaluation of functional capacity on an individual basis. CPET can unmask anomalies in the integrated functions of the respiratory, cardiovascular, metabolic, peripheral muscle and neurosensory systems in ILDs. CPET uniquely provides an evaluation of all above aspects and can help clinicians shape ILD patient management. Preliminary evidence suggests that CPET may also generate valuable prognostic information in ILDs and can be used to shed light on the presence of associated pulmonary hypertension. This review aims to provide comprehensive and updated evidence concerning the clinical utility of CPET in ILD patients, with particular focus on the physiological and clinical value of ventilatory efficiency (V˙E/V˙CO2).

Evaluation of long-term sequelae by cardiopulmonary exercise testing 12 months after hospitalization for critical COVID-19

“…However, increasing VD/VT during exercise is mostly sensitive for pulmonary vascular disease [30][31][32]. As in our study the majority of patients with normal exercise capacity had normal rest pulmonary function and no cardiovascular abnormalities, the increase of physiological dead space ventilation associated to a low peak PetCO 2 may point to pulmonary vascular disease.…”

Pathogenesis, clinical features, and phenotypes of pulmonary hypertension associated with interstitial lung disease: A consensus statement from the Pulmonary Vascular Research Institute's Innovative Drug Development Initiative ‐ Group 3 Pulmonary Hypertension

“…In IPF, ventilatory efficiency during exercise, expressed by VE/VCO 2 , has been shown 91 , 92 , 93 as the best predictor of PH during cardiopulmonary exercise testing (CPET). This parameter together with the peak oxygen consumption were able to discriminate 94 abnormal response to exercise in ILD patients, which might be a hallmark of early pulmonary vasculopathy.…”

Recent advances in the management of pulmonary hypertension with interstitial lung disease

“…These abnormalities lead to progressive worsening of aerobic capacity and exercise tolerance. Cardiopulmonary exercise testing (CPET) can augment the pathophysiological abnormalities that pulmonary hypertension imposes on patients with ILD [ 63 ]. These pathophysiological derangements are responsible for characteristic differences observed during CPET and potentially identify patients who are at increased risk of pulmonary hypertension.…”