Every so often, someone tells me a story that starts like this:

“My heart suddenly started racing. It felt irregular, like it was skipping around. I thought it was anxiety, but something didn’t feel right.”

I’ve heard that same description more times than I can count. Sometimes it is anxiety. Other times, it’s atrial fibrillation, or A-fib.

A-fib is a common heart rhythm problem, especially as we get older. It happens when the heart’s upper chambers, called the atria, stop beating in a steady, coordinated way and begin to quiver instead. When that happens, the heartbeat can become irregular and sometimes very fast.

People describe A-fib in different ways. Some say it feels like fluttering or pounding. Others say it feels like a fish flopping in their chest. Some people feel short of breath, dizzy or lightheaded. Others feel nothing at all and only discover it during a routine checkup or after getting an alert from a smartwatch.

A-fib can be frightening, especially the first time it happens. But the biggest concern is not just how it feels. It’s the increased risk of stroke.

When the atria don’t contract properly, blood can pool in the heart. Over time, that pooled blood can form a clot. If the clot breaks loose, it can travel to the brain and cause a stroke. That is why doctors take A-fib seriously, even when symptoms are mild or come and go.

If you experience   a sudden irregular heartbeat, especially with chest pain, dizziness, fainting or shortness of breath, it’s important to get checked.

Long-term treatment often includes medication to reduce stroke risk. These medications are commonly called blood thinners, though they do not actually thin the blood. 

Some people also ask about supplements, such as ubiquinol or taurine. These may be helpful for some individuals, but they are not a substitute for medical treatment. Always talk with your cardiologist before taking supplements, especially if you’re already on heart medications or blood thinners.

It’s also important to look for underlying triggers. Poor sleep, especially untreated sleep apnea, is one of the most underdiagnosed contributors to A-fib. Alcohol can also play a role, even in people with otherwise healthy hearts. Some episodes happen after a night of drinking. Dehydration, electrolyte imbalances and stress can also make the heart more irritable.

The good news is that A-fib is manageable. With proper evaluation, the right treatment plan and attention to possible triggers, many people with A-fib continue to live full, active lives.

The key is not to ignore it, and not to panic either. If your heart feels “off,” trust that instinct. Get it checked.