Thienopyridine ResistancePrevalence and Level of Thienopyridine Resistance Seen in a Contemporary Percutaneous Coronary Intervention or Coronary Artery Bypass Graft Population

Inclusion Criteria:

1. Patient >18 years old.
2. PCI group only: Patient scheduled to undergo cardiac catheterization or underwent percutaneous coronary intervention (PCI), during hospital stay.
3. CABG group only: Patient is scheduled to undergo, or has underwent, coronary artery bypass surgery with at least one saphenous vein graft.
4. Treated with a loading dose of clopidogrel or prasugrel at least 6 hours prior to the blood draw, or on a maintenance dose of clopidogrel or prasugrel for a minimum of 5 days.
5. Genetic testing subgroup only: Patient has undergone PCI (only), and has been treated with a thienopyridine as in 4.

Exclusion Criteria:

1. Known allergies to aspirin, clopidogrel, or prasugrel;
2. Use of a glycoprotein (GP) IIb/IIIa within 8 hours of the blood draw;
3. Patient known to be pregnant or lactating;
4. Patient with known history of bleeding diathesis or currently active bleeding;
5. Platelet count <100,000/mm the day of the blood draw;
6. Hematocrit <25% the day of the blood draw;
7. On warfarin therapy at the time of the blood draw;
8. Known blood transfusion within the preceding 10 days of the blood draw;
9. Patient who has received NSAID (not including ASA) within preceding 24 hours of the blood draw;
10. Any significant medical condition which in the investigator's opinion may interfere with the patient's optimal participation in the study.