For many cases of sudden cardiac arrest, the person will have had underlying cardiac disease whose symptoms were either so mild they didn't notice it, or present but ignored or written off as "heartburn" or "getting old". Any cardiac symptoms, no matter how mild or transient, should be reported to your physician.
I can personally vouch for this. I didn't have a heart attack, but had mild discomfort walking up a long hill. After putting it off for quite a while, I went to the doctor. After a few other tests, he sent me for an echo stress test, which showed up some blocked coronary arteries. They did an angiogram that afternoon and inserted two stents in the arteries. This is an amazing procedure, by the way. I spent exactly one night in the hospital and suffered very little discomfort.
"Get it checked" is good advice. I was on my way to a heart attack. BTW, I passed my follow-up stress test with flying colors, and am anxious to get out in the mountains again.