Is there a reason that you have a cardiologist? Did the cardiologist tell you it was PVC's? Those cause fluttering and are benign- no danger- but can be uncomfortable. I had them before a period for years, until menopause and was always told it was nothing to worry about.

Have you worn a monitor? If you have atrial fibrillation, that does need treatment. But "fluttering" sounds like PVC's and since your doc is unconcerned, that seems like what you are experiencing-?

Many triggers can cause.the heart to flutter. Stress, anxiety, chocolate, alcohol, any stimulant that causes the body to produce a shot adrenaline to your heart. Next time it happens, take notice to what happened right before it. A flutter may simply be the the shock that triggered it. It could mean nothing or it could be the start of a problem. The SA node in the upper right Atrial Chamber is the pacemaker of the heart. It produces an electrical pulse signal that tells the heart to pump, (a heartbeat). If it messes up, it could send more than a single beat, the flutter(palpitations) you feel. As long as it’s not constantly doing it, I’d say your cardiologist is correct. But if it gets worse, say multiple times in a row, they’ll check you out. Just take notice to what may have triggered it to happen and avoid it.