The novel coronavirus that’s hitchhiked across the globe may be innocuous for some, but it appears to be particularly dangerous for people with heart disease. More than 10% of COVID-19 patients with heart disease have ultimately died from the infection, according to a massive review of over 70,000 patients in China, where healthcare workers have been battling the virus for the past four months. That’s a rate about five times greater than the general affected population in the Chinese study, and nearly 10 times greater than the overall U.S. COVID-19 mortality rate in the most recent Centers for Disease Control report.
“Patients with cardiovascular disease are already starting out behind,” says Mitchell Elkind, M.D., a neurologist and epidemiologist at Columbia University, referring to the compromised ability of the heart to pump blood in people with heart disease. “It doesn’t take as much respiratory trouble to tip them over the edge.”
While the virus is still too new for researchers say with certainty what gives it such an edge over people with heart disease, two theories stand out:
- COVID-19 invades human cells through a protein abundant in the heart and blood vessels called ACE-2.
- The virus incites a feverish immune system response that wears on the lungs and places extra strain on an already damaged heart.
Why Your Heart Is Vulnerable
The new coronavirus might spell extra trouble for the heart because of how it interacts with your cells. The virus can only replicate in the human body once it binds to an ACE-2 receptor, which is found in the lungs, intestines, and kidneys as well as the heart and blood vessels. The virus might head straight to the heart to bind to these receptors, but researchers still don’t know for sure.
The same ACE-2 receptor also happens to be the target of a class of blood pressure medications known as ACE inhibitors that include Accupril, Altace, Vasotec and Zestril. In animal studies, these drugs have shown to increase the number of ACE-2 receptors in the heart.
In theory, ACE inhibitors could make heart and lung tissue more susceptible to infection by adding more receptors for the virus to bind to, but there’s no proof that’s the case. In fact, some reports have shown the opposite: these drugs can reduce injury from infections of other viruses and could be used to treat pneumonia from COVID-19, according to the American College of Cardiology.
Scientists’ understanding of this virus and how it interacts with drugs continues to shift. “It changes by the day,” says Eric Yang, M.D., a cardiologist at the University of California, Los Angeles Medical Center.
When the Immune System Overreacts
Scientists do know that once the virus begins to overtake cells in the body, the body naturally takes notice. If you become infected, your immune system mounts a defense that triggers inflammation and attacks the cells wherever the virus takes hold.
But this self-protection can inflict its own harm. Medical investigations of people who have died from COVID-19 reveal inflamed, injured heart tissue and damage to the lining of the arteries, causing a restriction of blood flow to the heart. That’s double trouble if you have heart disease, because your heart muscles are already weakened and “have less surge capacity to combat this,” says Mohammad Madjid, M.D., a cardiologist at the University of Texas Health Science Center in Houston.
In rare instances, the immune response can be so extreme that it triggers uncontrolled inflammation across the body, called a cytokine storm, thought to be a factor in the most severe cases of COVID-19. Dr. Madjid has studied this immune reaction in other infections. “It’s like the heart is on fire,” he says.
How to Protect Yourself
For anyone, the novel coronavirus sounds scary, and particularly so if you have an underlying condition like heart disease. But there are solid steps you can take to lower your risk of contracting COVID-19 and put yourself in a position to beat the infection if you do.
You’re already washing your hands a gazillion times a day, and you know way more than you want to about social distancing—keeping at least six feet away from other people and avoiding public spaces. But you should also skip any trips to the doctors that can be done over phone or video instead. “You don’t need to come in for a blood pressure check or cholesterol check with your heart disease right now,” says Dr. Yang.
And despite some questions about the role of various drugs in COVID-19, you absolutely should continue taking your regular heart disease medications, Dr. Madjid stresses. “The better your heart condition is treated, the better its capacity to act like a normal heart if the virus hits it,” he says. To that end, it’s also a good time to eat healthy and take (solitary) walks around the block. No, it won’t keep you from getting the coronavirus—but it will help you stay strong to fight it if you do.