key: cord-1033111-3n3anivr
authors: Biondi, Max; Gulati, Mridu; Possick, Jennifer; Joseph, Phillip; Singh, Inderjit; Lutchmansingh, Denyse
title: UNEXPLAINED DYSPNEA IN A PATIENT WITH A HISTORY OF COVID-19
date: 2021-10-31
journal: Chest
DOI: 10.1016/j.chest.2021.07.2054
sha: 54a91b8f1ffa1f514779a595447697fc0ea33c7c
doc_id: 1033111
cord_uid: 3n3anivr

nan

infection, at least 20% of patients experience persistent exertional limitation, most commonly dyspnea and fatigue. While severity of illness can be associated with persistence of symptoms, many patients with ongoing dyspnea had mild acute disease manifestation and did not require hospitalization. Here we describe a case of persistent dyspnea following COVID-19 infection.

A 49-year-old woman without significant medical history was referred for evaluation of exertional dyspnea following COVID-19 infection. Physical exam was unremarkable and pulmonary function tests were normal. A chest CT, resting right heart catheterization, echocardiogram, and 24-hour Holter were unremarkable. Given lack of improvement after 12 months, she underwent invasive cardiopulmonary exercise testing (iCPET). Results showed a depressed peak O2 consumption (VO2 MAX) at 69% predicted along with preserved peak exercise cardiac output of 137% predicted. Based on the direct Fick equation, depressed aerobic capacity was a result of a peripheral limitation to exercise due to impairment in oxygen extraction. This was supported by an elevated peak mixed venous saturation and narrowed peak arterial-venous oxygen content difference.

DISCUSSION: Decreased aerobic capacity from impaired oxygen extraction has been described in patients with connective tissue disorders due to impaired microvascular dilation.1 Recent studies have shown altered systemic microvasculature function with COVID-19 inflammation which may account for the impairment in oxygen extraction seen in our patient.2, 3 We propose that COVID-19 induced microvascular dysfunction may limit recovery after the acute phase of illness and present a plausible explanation for ongoing dyspnea in those with otherwise normal cardiopulmonary function.

CONCLUSIONS: Systemic microvascular dysfunction may occur in patients with a history of COVID19, resulting in impaired peripheral oxygen extraction and persistent dyspnea after resolution of acute infection. Further studies are needed to characterize this phenomenon. 

Systemic microvascular dysfunction in COVID-19

Importance of cardiopulmonary exercise testing amongst subjects recovering from COVID-19