The virus that causes COVID can directly infect plaque cells in the arteries

LEILA FADEL, HOST:

A new study tells us that the virus that causes COVID can infect plaque cells in the arteries. That could explain why some COVID patients may be at risk of heart attack or stroke in the months after their infection. NPR's Allison Aubrey reports.

ALLISON AUBREY, BYLINE: Doctors first noticed the connection between COVID and cardiovascular problems early in the pandemic, especially among people with preexisting conditions. And Dr. Leslie Cooper, a cardiologist at the Mayo Clinic in Florida, says several studies, including a VA study with more than 100,000 people, have pointed to a higher risk of heart attacks and more.

LESLIE COOPER: There are a number of data sets that show that cardiovascular complications, stroke and thromboembolism - meaning blood clots - are more common. And the U.S. VA data is pretty robust.

AUBREY: The question has been, why? A study published in the journal Nature Cardiovascular Research offers some clues. Researchers at NYU analyzed the arteries of men and women who had died of severe COVID, all of whom had preexisting heart trouble. They found direct evidence that the virus had infected cells in the blood vessels, specifically in plaque cells. Here's study author Dr. Chiara Giannarelli, a cardiologist at NYU.

CHIARA GIANNARELLI: We were able to see that the virus is able to infect the vasculature in the heart that supplies the blood to the heart. And the cells were less able to clear up the virus.

AUBREY: Meaning the virus may persist in these cells. Dr. Charis Antoniades is chair of cardiovascular medicine at the University of Oxford. He says the findings are significant and can help explain why people who have a buildup of fatty plaque in their blood vessels, which puts them at risk of heart attacks and strokes, may have increased risk after a severe COVID infection.

CHARIS ANTONIADES: This is pretty important because if the plaque get inflamed because of the virus, then they get vulnerable.

AUBREY: Vulnerable because the inflammation could cause the plaque to rupture or break off, which could lead to a heart attack or stroke. Now, all of the people in the study died in the first year of the pandemic, in 2020 or 2021. And now that most of the population has some immunity from a combination of infection and vaccinations, the question is whether a COVID infection could still have such an effect on the cardiovascular system. Physicians say it can depend on the health of the patient and their preexisting conditions. Here's Dr. Emily Lau, a cardiologist at Massachusetts General Hospital.

EMILY LAU: At the fundamental level, the real relationship between COVID-19 infection and cardiovascular disease risk is inflammation. In particular, we know that COVID-19 virus really mounts a very exuberant inflammatory response.

AUBREY: She says, among some of her patients, COVID can still be risky. Even though new variants may be less virulent and most people have some immunity, a severe COVID infection can take its toll, just as the flu can. Prior research has shown that among older people at higher risk, the flu virus can increase the risk of a heart attack in the months after an infection in the same way it's been shown with COVID. But she says there is a step people can take to protect themselves.

LAU: As a cardiologist, I can't emphasize enough how important it is for every patient, especially those with existing heart disease or risk factors for heart disease, to be vaccinated against COVID-19 and boosted.

AUBREY: She says, with some rare exceptions, vaccination is still important to prevent a severe infection, which can be harmful.

LAU: Severe COVID infection is really a significant stress on one's cardiovascular system.

AUBREY: Which could increase both the short-term and long-term outcomes related to the heart.

Allison Aubrey, NPR News.

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