The objective of this study is to compare the Cypher Select-TM Sirolimus Eluting Stent (SES) with the SONIC-TM Bare Metal Stent (BMS) in the treatment of Chronic Total Occlusion lesions (CTO). The primary hypothesis is that, at 8-month follow-up, the minimal luminal diameter (MLD) of the coronary segment treated with stent implantation in CTO lesions is significantly larger with the use of SES compared to BMS. The treated segment is defined as the segment covered by the stent(s) plus 5 mm proximally and distally to the stent(s).