Would a patient sheduled for open heart surgery need to have heparin in their system before surgery?

Added 12 weeks ago:

The hospital has had an IV heparin drip in my husband for 7 days he is scheduled for a graduple bypass on tuesday. The surgeon first reported that he would not do the surgery if he wasn't taken off this med prior to 6 days, he has now stated he meant the plavix, but on the web it does state that heparin needs to be out of your system for 4 days at least. Should I be concerned, and how can I get the doctor to postpone the surgery until safe.