It seems like we have been in the midst of the COVID-19 pandemic forever, but in reality the disease has been around for less than one year. That’s not a long time, as far as new diseases go, and scientists are learning more and more about it all the time. Indeed, given this relatively short timespan, it’s hard to know what the long-term effects of the coronavirus may be. However, clinicians and researchers are noticing a connection between COVID-19 and heart disease.
In particular, patients infected by the novel coronavirus often develop a worrisome inflammation of the heart muscle. Known as myocarditis, this inflammation potentially can produce serious heart disease. In a July 2020 study published in JAMA Cardiology, researchers discovered that 78 out of 100 patients recovering from COVID-19 had some kind of cardiac impairment, and 60 of those had myocarditis after recovering, independent of whether or not they had preexisting conditions or how severe their COVID-19 symptoms were.
“We were not expecting that,” says Dr. Sandra Chaparro, a cardiologist at the Miami Cardiac and Vascular Institute who specializes in heart failure and transplantation cardiology and serves as the director of advanced heart failure. That study’s small sample size makes it hard to know just how widespread the incidence of myocarditis really is, she says. But anecdotal evidence from around the world – including at her institute, which has treated several patients with the condition – suggests it’s worth monitoring.
“We’ve seen it in young and old patients,” Chaparro says. One patient in his 40s recovered from COVID-19 but had signs of heart damage after. However, the connection is still far from clear. “Sometimes it’s hard to figure out if it was caused by something else or a preexisting condition. And we don’t know what the rate (of myocarditis) is of asymptomatic patients,” she adds. But the data and case studies are raising alarms.
What Is Myocarditis?
Myocarditis is any inflammation of the heart muscle, says Dr. Karol Watson, a cardiologist and a professor of medicine/cardiology at the David Geffen School of Medicine at UCLA. This inflammation can have many causes. A virus like the coronavirus is one of the most common causes, but bacterial infections, chemotherapy drugs or a dysfunctional immune system may also be behind it.
Myocarditis can disrupt the heart’s ability to pump blood and impair the electrical signaling that keeps it beating regularly. It can be mild, and most people do not have a lot of symptoms, if any, Chaparro says. In severe cases, myocarditis can cause abnormal heart rhythms, heart muscle disease and heart failure. These patients may need medication and/or mechanical support, like heart pumps, and a small number of patients require heart transplant, she says.
How Does COVID-19 Affect the Heart?
The coronavirus may cause inflammation in up to three ways. “Like any virus, it can directly attack the heart muscle, causing inflammation and myocarditis,” says Watson, who is also director of the UCLA Women’s Cardiovascular Health Center and the