I would be concerned about this, and ask my doctor to get in touch with the manufacturer of your stent, or consult with a Hematologist at the very least.
DRUG INTERACTIONS with Plavix (clopidogrel):
Warfarin (coumadin): Because of the increased risk of bleeding, the concomitant administration of Warfarin with Plavix should be undertaken with caution. (See PRECAUTIONS - General.)
At high concentrations in vitro, clopidogrel inhibits P450 (C). Accordingly, Plavix may interfere with the metabolism of phenytoin, tamoxifen, tolbutamide, warfarin, torsemide, fluvastatin, and many non-steroidal anti-inflammatory agents, but there are no data with which to predict the magnitude of these interactions. Caution should be used when any of these drugs is co administered with Plavix.
Best of luck,