XIENCE V® USA Dual Antiplatelet Therapy (DAPT) Cohort

Inclusion Criteria: * Patients who are enrolled into the XIENCE V USA Study Phase I * The patient agrees to participate in this study by signing the Institutional Review Board (IRB) approved informed consent form. Alternatively, the patient's legally authorized representative agrees to the patient's participation in this study and signs the informed consent form. Exclusion Criteria: * The inability to obtain an informed consent is an exclusion criterion. Patients must meet the following criteria to be eligible for randomization in the study: * Patient is "12 Month Clear": "12-Month Clear" patients are free from death, MI, stroke, repeat coronary revascularization, major bleeding - "severe" or "moderate" by GUSTO classification, and ST 12 months after stent implantation. Staged PCI is allowed (same stent type as index); repeat PCI and peri-procedural myocardial infarction occurring with the index procedure or repeat procedure within the first 6 weeks will not be considered exclusionary events for the definition of "12 Month Clear". * Patient is "DAPT Compliant": During the open label portion of this study (time 0-12 months), a patient is considered compliant with the thienopyridine therapy for the purposes of eligibility if they take between 80% and 120% of the prescribed drug in a given period without an interruption of therapy longer than 14 days. This information will be ascertained via data collected at the patient interviews at 6 and 12 months post-procedure. Complia…