Patients with long COVID-19 may suffer from persistent heart and lung inflammation for almost a year following the infection, a study has revealed.
COVID caused by SARS-CoV-2 infection may potentially put these persons at a higher risk of cardiac arrest and pulmonary conditions, even if the standard medical tests exhibit normal results, the study published in Journal of Nuclear Medicine stated.
The study is the largest of its kind to uncover major abnormalities in cardiovascular and pulmonary tissues. The researchers also discovered altered levels of circulating immune-regulating proteins among long COVID patients.
These abnormalities could serve as early warning signs of diseases such as heart failure, valvular heart disease, and pulmonary hypertension, according to a statement from the Mount Sinai Fuster Heart Hospital in the United States.
The researchers studied 100 patients from the hospital who tested positive for COVID-19 infection between December 2020 and July 2021, with complaints of persistent cardiopulmonary symptoms.
A majority of the patients did not have a history of cardiovascular disease. About 300 days post COVID-19 infection, 91 of the total participants underwent hybrid 18F-fluorodeoxyglucose positron emission tomography combined with magnetic resonance imaging (PET/MRI). The advanced imaging method is used to simultaneously detect structural and metabolic abnormalities.
Of these 52 patients, around 57 per cent showed evidence of inflammation impacting the heart muscle pericardium — a thin sac surrounding the heart, heart valves, especially the mitral valve and the aortic and pulmonary blood vessels. In many cases, more than one of these regions was found to be affected.
The scans revealed that 22 patients showed abnormalities in heart muscle, characterised by scarring and thickening of the tissue. These abnormalities are similar to inflammation or chronic disease of the heart muscle.
“Pericardial involvement was seen in 20 patients, indicating either inflammation or effusion, a build-up of fluid. Inflammation near the mitral valve was identified in 10 participants, and vascular inflammation involving the aorta or pulmonary arteries was observed in 28 participants. All abnormalities were associated with persistent symptoms such as chest pain, fatigue, and shortness of breath,” the statement said.
Simultaneously, researchers also conducted plasma protein analysis which exhibited abnormalities in important biomarkers that are responsible for regulating inflammation and immune signalling.
These observations, correlated with the imaging of abnormal patterns, provided molecular-level confirmation of persistent inflammation.
To confirm the results, a control group of nine individuals with positive COVID-19 infection but not exhibiting symptoms of lingering cardiopulmonary were studied during March to October 2023. The group underwent the same imaging and blood testing without showing any inflammatory changes observed in the symptomatic long COVID cohort, the authors explained.
“We found a range of cardiopulmonary inflammatory patterns, backed by abnormal protein profiles,” said Maria Trivieri, corresponding author and associate professor of medicine (Cardiology), and diagnostic, molecular and interventional radiology at the Icahn School of Medicine.
Trivieri added, “These insights could have far-reaching implications for diagnosis and surveillance. If patients experience lingering symptoms such as shortness of breath, they should consult a physician for further evaluation. Our results should also raise awareness among clinicians to consider a patient’s COVID history and evaluate persistent symptoms more thoroughly.”
“This paper provides more data to highlight that SARS-CoV-2 is a virus that profoundly affects vascular health and that every new infection can do damage. Infection prevention is crucial,” said David Putrino, the Nash Family Director of Mount Sinai’s Cohen Center for Recovery from Complex Chronic Illness.
Concluding that long COVID has become a major public health concern, and the findings demonstrate how the virus significantly affects the heart and lungs over time, Trivieri, said, “We believe long COVID results in an inflammatory response that may predispose patients to premature coronary artery disease, pulmonary hypertension, and valvular damage such as stenosis.”
Another study published in the journal Nature Immunology revealed distinct changes in the immune systems of COVID-19 survivors, indicating the severity of their lung damage.
The researchers from University of Virginia School of Medicine, for the first time, were able to distinguish between immune patterns in patients linked to lung injury.