It depends on the type of irregularity. Some occasional extra beats are considered ok for surgery, but others may not. It would be best to discuss with your plastic surgeon, get an EKG and possibly a Cardiology consultation depending on the EKG results. Please make sure your plastic surgeon is aware as you don't want to take unnecessary risks.
If you have an abnormality on your EKG such as a irregular heart beat you will need to have it worked up medically prior to surgery. The prudent thing to do would be to have a cardiology evaluation.