Irregular heart beats after exercise

[Azimo]

Hi,
After a long run (usually 10 miles or more), I experienced irregular heart beats or fluttering of the heart a day or 2 later. Sometimes the heart beats really fast, or just plain irregular.  I do get lightheaded when the heart beat is fast or it it is irregular (e.g. missing a beat), I'm uneasy and feel uncomfortable.  This goes away after a week or so.
I would consider myself phyisically healthy. I run on average 12 to 15 miles a week, up to 20 miles per week and have completed 3 half marathons this year.
Should I be worried?

[merileegal]

Any time your heart does something irregular it is best to get it checked out by a good cardiologist. You only get one so you better know what is going on with it. Many of us here have irregular heart beats of a variety of different kinds. Some heart beats are benign while others are more serious. Both types require some people to be on meds to keep the heart beating like it should. There are many  possibilities for your irregular heart beat and only your doctor can tell you what kind you have after monitoring of some kind. Good luck.

[MichelleP_3811]

You should be checked out by your doctor but it sounds like premature ventricular contractions.  If your heart is structurally fine then they are nothing to be concerned about but you should go and get a check up.  Good luck.