Lung Perfusion Disturbances Detected with MRI in Non-Hospitalized Post-COVID-19 Individuals with Dyspnea 3 -13 Months after the Acute Disease

BackgroundDyspnea is a prevalent symptom in the post-COVID-19 condition, though its mechanisms are largely unknown. Lung perfusion abnormalities have been reported in acute COVID-19 and could be suspected in patients with lingering dyspnea after the acute phase.ObjectivesTo detect pulmonary perfusion disturbances in non-hospitalized post-COVID condition with persistent dyspnea 4-13 months after the disease onset.MethodsNon-hospitalized individuals reporting persistent dyspnea after COVID-19 and matched healthy controls were prospectively recruited between October 2020 and May 2021 to undergo pulmonary dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), six-minute walk test, and self-reported scales questionnaires on dyspnea and physical activity. The DCE-MRI perfusion images were quantified into two parametric values: mean time-to-peak (TTP) and TTP ratio.ResultsTwenty-eight persons with post-COVID condition and persistent dyspnea (mean age 46.5±8.0 years, 75% women) and 22 healthy controls (mean age 44.1±10.8 years, 73% women) were included. The post-COVID group had higher mean pulmonary TTP (0.43±0.04 vs. 0.41±0.03, P=0.011) and higher TTP ratio (0.096±0.052 vs. 0.068±0.027, P=0.032). Notably, post-COVID males had the highest values (mean TTP 0.47±0.02, TTP ratio 0.160±0.039, PConclusionsLung perfusion disturbances were detected in males reporting post-COVID dyspnea using perfusion parameters from DCE-MRI. The distinct sex difference has implications for understanding the perplexing post-COVID pathophysiology and warrants future studies. DCE-MRI could provide biomarkers for such studies.