Fear of coronary artery disease

I am a 67 YO male who ran for 20 years(40 miles/week). I quit running at age 57 and still walk 5 days a week(30-45 min). In March 2010, was having very localized chest pain & was told by my PCP it was not my heart. I went to a cardiologist in May 2010 and had EKG, nuclear stress test, holter,echo and eventually a heart cath due to a questionable area on the stress test that turned out to be nothing. Was told my coronary arteries were clear with no plaque and above average size with collateral circulation due to my years of running.I do suffer from PVCs/PACs and have had them as long as I can remember.HOWEVER, I still live in constant fear of having a heart attack. What are my odds? My total cholesterol is 163, LDLs are low, trigycerides are 70, but HDLs are very low at 37. BP is 130/80.Weight 154 at 5’8″. Should I be worried about this at all?