As far as Michelle Wilson knew, she'd recovered from Covid-19.
Wilson, 65, contracted the virus in November 2020. Her illness, she said, was mild, and she was feeling ready to go back to work as a nurse in St. Louis by early December.
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That's when her heart problems began.
"I literally woke up one morning, and my heart was racing and beating erratically," Wilson recalled. "I was having intense chest pain."
Fortunately, Wilson was not having a heart attack. But she did develop long-term heart problems, including high blood pressure, putting her at risk for further cardiovascular issues.
Despite her age, she had no prior medical history to suggest she was at risk for heart disease — other than Covid-19.
Indeed, it appears the coronavirus can leave patients at risk for heart problems for at least one year following infection, according to one of the largest analyses of post-Covid health effects to date.
The study, published last week in Nature Medicine, found that the illness increased the possibility of heart rhythm irregularities, as well as potentially deadly blood clots in the legs and lungs, in the year after an acute infection.
Covid also increased the risk for heart failure by 72 percent, heart attack by 63 percent and stroke by 52 percent — even among those, like Wilson, whose original illnesses were mild.
The study's lead author, Dr. Ziyad Al-Aly, a clinical epidemiologist at Washington University in St. Louis, said he and his colleagues expected to see some elevation in heart problems following Covid, but assumed it would be limited largely to people whose health wasn’t robust previously.
The elevated risk remained when researchers accounted for age and race, he said.
"It was a bit of a moment for us when we realized it was evident in all of these subgroups," Al-Aly said, "including younger adults, older adults, Black people, white people, people with obesity and those without."
"The risk was everywhere," he said.
Al-Aly's team examined the rates of new heart problems among 153,760 Covid patients for up to a year following their illness. The participants were patients who'd sought care within the Department of Veterans Affairs, and most were white men.
Cardiovascular outcomes were compared to two control groups: 5.6 million people without Covid, and another 5.9 million patients whose data was collected before the pandemic began.
Covid-19 patients in this study were infected before vaccines were available, so it is unclear how the shots might alter the findings.
But physicians on the front lines of treating Covid and its effects suspect vaccinations do cut heart risks because they reduce Covid infections in general.
"I've taken care of patients with heart problems" after Covid-19 infection, said Dr. Steve Nissen, a cardiologist at the Cleveland Clinic. "The vast majority are unvaccinated."
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That Covid-19 appears to increase long-term risks of cardiovascular problems is not surprising to doctors. Other viruses, such as influenza and certain enteroviruses, have long been known to carry the same risks.
"Anybody who is hospitalized with any kind of pneumonia that they acquire in the community has these risks for six to 12 months," said Dr. Donald Lloyd-Jones, president of the American Heart Association. "The open question for me is, is this something unique about Covid? Or is this the same story we already know?"
Covid's heart risks may be showing up with more regularity just because the virus spread so quickly.
"It's very concerning because so many people will be getting Covid in the next however many years, and so many have already gotten it," said Dr. Jennifer Haythe, co-director of the Women's Center for Cardiovascular Health at the Columbia University Irving Medical Center in New York. "This may really increase the burden of cardiovascular disease across the board."
Al-Aly's research is not the first to suggest long-term heart risks following Covid-19.
A study of recovered Covid patients in Germany found that 78 percent of patients had heart abnormalities. Swedish research, too, found an increased risk of heart attack and stroke following Covid-19.
It is not entirely clear how Covid could cause heart problems over the long term, though it is known that the virus can affect blood vessels all over the body and in multiple organs, including the heart.
For Wilson, the irregular heartbeat has endured.
She has had to sleep nearly upright for months.
"It got so bad that when I laid down, I couldn't sleep because my heart was so erratic," she said.
Her physicians are now monitoring her for any indication of heart failure.
Regardless of infection, the pandemic itself is also upping the risk of heart health problems.
"Too many patients are delaying getting back into their routine within the health care system," Lloyd-Jones said. "We've seen marked increases in overall blood pressure levels, weight gain, worsening control of diabetes, and all of those things are contributing to increased risk."
Anyone whose Covid recovery stalls, or who experiences a sudden onset of new symptoms, such as chest pain, intense muscle weakness or shortness of breath, should call 911 immediately, Lloyd-Jones said.
Those aren't just red flags, he said. "Those are flashing lights."
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