Although the optimal duration of clopidogrel (an anti-platelet agent) therapy has been established after bare metal stent implantation in the blood vessels of the heart, there is lack of consensus regarding the optimal duration of therapy after implantation of a drug eluting stents (DES). Current American College of Cardiology guidelines recommend clopidogrel use for at least one year in the absence of contraindications after DES implantation, while recognizing that the optimal duration remains unknown. While an extended clopidogrel therapy (that is beyond the current 1 year recommendation) may increase bleeding complication, it may reduce the rates of adverse cardiovascular events like heart attacks and repeat revascularization procedures. A clinical trial which randomizes patients with an uneventful one year course after a DES implantation, to an additional year of clopidogrel and aspirin therapy versus aspirin alone, will be able to answer the important question about the role of extended (2y) dual anti-platelet therapy with clopidogrel and aspirin after DES implants. The investigators hypothesize that clopidogrel discontinuation at 1 year post-DES implantation is associated with an increase in cardiovascular events during the one year of follow-up period.