It's probably something called enhanced automaticity. Which just means that some of the cells in the ventricle are irritable. I'll bet you $500 that if it was caught on an EKG they are coming from an area called the right ventricular outflow tract. No biggie, it's just the most common are for where they come from.
If your heart otherwise checks out, it doesn't mean the muscle is damaged or the muscle is getting diseased. I've had PVCs my entire life. I'm 48 now and my heart is still fine. I've had every test imaginable even while getting PVCs like crazy. I threw them like crazy once during a stress test and everyone gathered around. It was great. not. that was about 10 years ago.
During those years the PVCs come and go. They get worse, get better, in 2009 I had a MAJOR flare that lasted 9 months. I run, row, and bike more now than when I was 19. I'll get PVCs too as I start to exercise. Sometimes as I warm up, sometimes as a I cool down, sometimes in the height of it all, and sometimes none at all. I gave up on trying to interpret what it meant because there's no pattern.