Heart disease isn’t only a later-in-life concern. A May 2025 study in the Journal of the American Heart Association showed heart disease rates are climbing among younger people, especially men. One factor driving this trend? Myocarditis—one of the leading causes of heart failure, including among young people—is also on the rise, the researchers say.
Myocarditis is inflammation of the heart muscle, says Christopher Mahida, MD, a physician specializing in interventional cardiology at Mercy Health in Ohio. “It’s dangerous because it can weaken the heart, leading to heart failure,” Dr. Mahida says. This inflammation can reduce the heart’s pumping ability as well. “It may also cause abnormal heart rhythms (arrhythmias), which can lead to sudden cardiac arrest.”
One patient explains how a mild case of COVID nearly resulted in the need for a heart transplant—and the one symptom of myocarditis he wishes everyone knew about.
How I knew I had myocarditis
As told by Tim Shuckman, 46, to Leslie Finlay, MPA
“In 2024, I was probably in the best shape of my life since college,” Tim says. “Then right around this time last year, I came down with COVID following a work trip. It really wasn’t bad, I felt like I had the flu for a few days—back up and running and working out within probably four days.”
“Then about two weeks after that, I had what I thought was a rebound of COVID.” Tim’s symptoms included fluid in his lungs, shortness of breath, lethargy, and swelling in his limbs. “I went back to the doctor and got diagnosed with pneumonia—well, what we thought was pneumonia.”
He continued his daily activities with modifications as needed, but one day, he hit a wall. “I actually ran three and a half miles that morning and was like, Something’s off. [Then] I was on a work Zoom call and I could barely speak.”
Tim says that later that night, “Anytime I would try to lie flat, after about an hour it was like, asthmatic—I couldn’t breathe at all and I’d kind of shoot up out of bed, I’d be hunched over and [trying to] catch my breath.”
“I come to find out that’s like the number one sign of heart failure: your lungs build up all this fluid in them and you can’t breathe,” he says. At this point, Tim headed straight to the hospital emergency department, arriving in such poor condition that he was flown to a specialized hospital.
Severe myocarditis diagnosis
“I don’t remember any of this, but Dr. Mahida was the physician who decided to immediately put in an Impella pump to help my heart … a call which, ultimately, I believe ended up saving my life.”
An Impella pump is a small mechanical device that temporarily helps the heart pump, allowing it to rest and recover. Coincidentally, the company where Tim serves as chief commercial officer was involved in this device’s clinical trials. “I was blown away by that,” he says. “Like, full circle, the work I do every day in some way actually helped save my own life.”
The pump is a short-term solution, however, and Dr. Mahida made the call to transfer Tim to a hospital with a transplant center. “Mild [myocarditis] cases often resolve on their own, and most patients may have minimal symptoms,” Dr. Mahida says. “Moderate cases may require brief hospitalizations, including management with medications.”
