Researchers at Houston Methodist Hospital have found that cardiovascular injury may be responsible for at least some of the challenges that many COVID-19 patients are still experiencing during exercise and physical exertion after their initial illness. Learn more about what scientists uncovered about lingering blood vessel damage post-COVID.

What the researchers did

In their study published in the Journal of the American College of Cardiology: Cardiovascular Imaging, the investigators explained that, while it was known that endothelial cells, which line the walls of the heart and blood vessels and control fluid flow, could be injured during COVID-19, it’s been unclear whether endothelial inflammation persists after infection and what effect(s) this may have on cardiovascular health. Answering this question was the focus of their research. 

For this study, 101 Long COVID patients were matched to 292 controls with no COVID history.

• The average participant age was 65 years, and 51% were men.
• Patients were matched by age, sex, and cardiovascular risk factors such as diabetes and high blood pressure. 
• Advanced imaging technology was used to assess impacts on the heart.
• Imaging was done approximately 190 after COVID-19 infection.

What they found

The study found significant vascular impacts of COVID-19.

• The most common reason for imaging was chest pain (66% in Long COVID patients versus 54% in controls), followed by breathlessness (41% versus 37%).
• Significantly more Long COVID patients had reduced blood flow than controls (58% versus 28%).
• Endothelial cell function was reduced by 20% in Long COVID participants, which could lead to greater chest pain and breathing difficulty during exercise or other strenuous activity. 
• Imaging revealed that Long COVID patients had twice the likelihood as controls did of having unhealthy endothelial cells.

Endothelial cells are critical in dilating the arteries for increased blood flow to the heart. Said study co-author and cardiologist Mouaz Al-Mallah, M.D., “When a patient exercises, they need a little bit more blood delivered to the heart to be able to provide blood to the entire body. But in some patients with COVID, we noted that it’s not increasing to the degree that it should be.”

What it means

The study provides insight into how COVID-19 affects the heart, along with its relationship to Long COVID symptoms. Ultimately, the findings revealed that people with damaged epithelial cells are at greater risk for:

• Heart failure,
• Unexpected catheterization,
• Bypass surgery, and
• Higher mortality rates.

“We know that this condition exists in other situations like in diabetics,” Al-Mallah said, “but has not been described before among COVID survivors.”

As the Long COVID participants likely had the virus’ delta and beta variants, Al-Mallah would like to see more research into whether the following variables factor into COVID’s lingering cardiovascular effects:

• Variant type,
• COVID severity, and
• Time from infection.

He hopes that his research results in expediting better treatments and eventual prevention.

*Willa Ernst, S. (2022, August 19). New study offers clues as to how long COVID affects the heart. Houston Public Media. https://www.houstonpublicmedia.org/articles/news/health-science/2022/08/19/431146/new-study-offer-clues-as-to-how-long-covid-affects-the-heart