Scientists have gained insight into how COVID-19 affects the heart.

Scientists have gained insight into how COVID-19 affects the heart.

COVID-19 Virus Found to Inflame Coronary Arteries, Increasing Risk of Heart Disease and Stroke

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By Cara Murez HealthDay Reporter

New research has shown that the COVID-19 virus can directly infect coronary arteries, leading to the inflammation of fatty plaque within them. This discovery indicates that individuals who contract COVID-19 may have a higher risk of developing heart disease and stroke. Furthermore, it may explain why people with pre-existing heart conditions experience more heart-related complications.

Since the beginning of the pandemic, it has been known that individuals who have had COVID-19 face an increased risk of cardiovascular disease or stroke for up to one year after infection. Michelle Olive, acting associate director of the Basic and Early Translational Research Program at the U.S. National Heart, Lung, and Blood Institute (NHLBI), states that this recent discovery sheds light on the reasons behind this increased risk.

Although the study primarily focused on older individuals with fatty plaques in the arteries who died from COVID-19, the findings may have broader implications for anyone who contracts the virus. Previous research has shown that COVID-19 can directly infect tissues such as the brain and lungs. Once the virus infects the cells, the immune system sends in white blood cells called macrophages to help clear the virus. These macrophages also assist in removing cholesterol from the arteries. However, when macrophages become overloaded with cholesterol, they transform into foam cells, a specialized type of cell within arterial plaques.

Senior author Dr. Chiara Giannarelli, an associate professor of medicine and pathology at New York University’s Grossman School of Medicine, theorized that if the SARS-CoV-2 virus can infect arterial cells, the macrophages may increase inflammation in existing plaque. To test this theory, the researchers analyzed tissue from the coronary arteries and plaque of individuals who died from COVID-19. They were able to confirm the presence of the virus in these tissues.

They further conducted experiments with arterial and plaque cells, including macrophages and foam cells, from healthy patients. In the lab, they infected these cells with the virus and found that the virus could indeed infect them. The researchers observed that the virus infects macrophages at a higher rate than other arterial cells, with foam cells filled with cholesterol being the most susceptible to infection. The study suggests that these foam cells could act as a reservoir for the virus within atherosclerotic plaques. Individuals with more plaque build-up may experience more severe or persistent COVID-19 infections.

Additionally, the researchers noted the release of cytokines, which are known to increase inflammation and promote plaque formation. This finding may help explain why individuals with underlying plaque build-up who subsequently contract COVID-19 may experience heart-related complications long after recovering from the infection.

Michelle Olive, in an NHLBI news release, emphasizes the significance of this study in enhancing our understanding of COVID-19. She states, “This study is incredibly important as it adds to the larger body of work to better understand COVID-19. This is just one more study that demonstrates how the virus both infects and causes inflammation in many cells and tissues throughout the body. Ultimately, this is information that will inform future research on both acute and long COVID.”

Although the study was conducted on a small group of older individuals and based on the original virus strains that circulated between May 2020 and May 2021 in New York City, the researchers caution that the findings cannot be generalized to other virus strains or younger, healthy individuals.

This research was funded by the U.S. National Institutes of Health and was published online on September 28 in Nature Cardiovascular Research.

More information

The U.S. Centers for Disease Control and Prevention provides more information on COVID-19.

Sources

  • U.S. National Heart, Lung, and Blood Institute, news release, Sept. 28, 2023