With some exceptions, generally your good or bad credit does not follow you around the world. However, if your creditors end up suing you (in the US) and winning civil judgments against you (because you won't be there to defend yourself), it can cause visa and naturalization complications down the line.
I would encourage you to obtain a free copy of your credit report from all three bureaus from
www.annualcreditreport.com, find out what you owe and to whom.
Also, there are forums such as creditboards.com and myfico.com where you can find out how to deal with anything you find.
Or, you could bury your head in the sand for now, but in an increasingly connected world, it could come back to bite you later.
(ETA: I don't think it's possible to file a change-of-address with the US Postal Service to an international destination. You would need to pay for a private forwarding service and have the USPS send your mail to them.)