Background: Dual antiplatelet therapy with aspirin and clopidogrel is recommended for patients after drug-eluting stent (DES) implantation; however, from when one can discontinue antiplatelet therapy after DES implantation in preparation for the surgical procedure has not been verified. We compared clinical and angiographic parameters between patients with or without stent thrombosis after discontinuation of antiplatelet therapy in preparation for the noncardiac surgical procedures. Methods and Results: From this single center registry from April 2003 to June 2006, we evaluated the clinical outcomes of discontinuing dual antiplatelet therapy in preparation for the noncardiac surgical procedures in 71 cases. Two patients (2.8%) developed subacute stent thrombosis after discontinuation of dual antiplatelet therapy. The risk factors such as diabetes, hypertension, smoking, and dyslipidemia were similar between the patients with or without stent thrombosis. The average duration of dual antiplatelet therapy before surgical procedure was 166.5 짹 159.1 days in the No Thrombosis Group and 24.0 짹 24.0 days in the Thrombosis Group (p=0.05). The average duration of discontinuing antiplatelet therapy before surgical procedure was 8.7 짹 6.3 days in the No Thrombosis Group and 8.0 짹 2.8 days in the Thrombosis Group (p=0.883). Two patients in the Thrombosis Group used Cypher whereas 62 patients (89.9%) in the No Thrombosis Group used Cypher. Two patients with subacute thrombosis underwent intermediate cardiac risk operation whereas 24 patients (35.3%) in the Thrombosis Group underwent intermediate cardiac risk operation (p=0.139). Multiple overlapping stenting was performed in 22 patients (31.9%) in the No Thrombosis Group whereas 2 patients with subacute thrombosis had single stenting. The average diameter and length of stents were similar between the 2 groups. Conclusion: At least 2 months of aspirin and clopidogrel administration before discontinuing antiplatelet therapy in preparation for the noncardiac surgical procedures was necessary in preventing stent thrombosis. A multicenter study with large number of participants is warranted to verify the predictors of stent thrombosis in preoperative consultation.