My Cardiologist agreed to stop both plavix and aspirin 48 hours before, then start 24 hours after. I had no problems.
What will happen will depend on why you have it prescribed...
If you had a heart attack and stents, this is one of the common reasons for Plavix and aspirin together.... If has already been more than 1 year from the episode, I think nothing will happen but you should ALWAYS check with your cardiologist before to stop it.
By the way, in my case my cardiologist got no problem to stop plavix but he did not allow under any circumstance, to stop aspirin, due to risk of suffering another HA.
Also be aware of many other "blood thinners" that you might be taking, like Omega-3, Taurin, Vitamin E.....
Jesus