Long-Term COVID-19 Effects on the Heart

Are you a COVID-19 ‘long-hauler’? Are you worried that your lingering exhaustion or shortness of breath indicate damage to your heart?

According to cardiologist and Assistant Professor of Clinical Medicine Stephen Andrew McCullough, MD, there is no clinical evidence that COVID-19 directly infects the heart muscle. “The evidence and rate of COVID-19 causing direct damage to the heart muscle are very low,” Dr. McCullough says. “There are certainly patients who have cardiac symptoms after recovering from COVID-19, but it’s hard to know if it’s heart disease itself or a hormonal imbalance that the virus has triggered, and that is causing people to have symptoms.”

Effects of Long COVID-19

As the pandemic begins its third year, patients who have recovered from COVID-19 are increasingly citing symptoms of ‘long COVID’, including persistent fatigue, palpitations, brain ‘fog,’ and shortness of breath. “Because patients are so symptomatic for a period of time after illness, they are limited in terms of living their everyday lives,” Dr. McCullough says. “They can’t exercise, they have trouble sleeping, they experience fatigue, shortness of breath and feel like their heart is racing out of their chest,” he adds.

Some medical experts associate these symptoms with heart damage, particularly a condition called myocarditis, which is direct inflammation of the heart muscle that can lead to an uneven heartbeat (arrhythmia) or heart failure. Yet, most patients’ symptoms almost never point to organic heart disease, Dr. McCullough says. “Patients see multiple providers who have difficulty diagnosing them because all their tests come back normal.”

Autonomic dysfunction in 'long COVID'

A more likely explanation for their cardiac symptoms is the dysfunction of the autonomic nervous system, stemming from a hormonal imbalance, Dr. McCullough explains. “The COVID-19 patient has all the classic symptoms of heart disease, but almost always ends up with normal cardiac testing. This is still clinically explainable, as it could be that the heart is responding to a hormonal imbalance that being infected with COVID-19 has caused and that has thrown the autonomic nervous system out of whack,” he says.

The autonomic nervous system controls bodily functions such as blood pressure, heart and breathing rates, body temperature, digestion, and metabolism. When this system malfunctions, so do the processes—like heartbeat and breathing--that it regulates. Although some experts attribute heart-related trouble such as myocarditis directly to COVID-19, Dr. McCullough says that ‘long Covid’ issues may actually be secondary to the hormonal imbalance that results in autonomic nervous system dysfunction. “If you have cardiac symptoms after recovering from Covid-19, then the most likely explanation is autonomic nervous system dysfunction,” he says.

Moreover, it’s patients’ immune response to COVID-19, not the virus itself, that leads to inflammation affecting the heart, he notes. This inflammation tends to affect younger people who have more robust immune systems, he says. “Seeing pericarditis (swelling and irritation of the thin, saclike tissue surrounding the heart) or myocarditis after vaccination is less common than seeing them after Covid-19, and they are incredibly rare during Covid-19 itself,” he says. “Only a handful of people have had myocarditis. What we’ve seen more commonly is autonomic nervous system dysfunction.”

Doctors don’t know who is at most at risk for autonomic nervous system dysfunction, Dr. McCullough says. They also do not know if it develops because patients are extra sensitive to hormonal imbalances or because COVID-19 has caused an over-secretion of hormones. “No one type of patient develops these heart problems,” Dr. McCullough says. “I’ve seen them in older and younger patients, women and men, patients who are anxious and not anxious.”

Benefits of Cardiovascular Exercise

Doctors do know, however, that regular exercise can correct the problem and its symptoms. “This is challenging because COVID-19 patients get symptomatic so quickly and it can take six months for their symptoms to go away,” Dr. McCullough says. “But they do get better if they stick to an exercise program.”

He urges recovering patients to increase their aerobic activity (brisk walking, jogging, swimming, or cycling) slowly and steadily, until they can do it for 30 minutes a day, five days a week. “You know the exercise is working if you are sweating at the end.”