All consecutive patients undergoing a coronary CTO procedures between November 2017 and November 2018 at the catheterization laboratories of Acibadem University Kocaeli Hospital, Memorial Hospital Istanbul and Adapazarı Education and Training Hospital were considered to be enrolled in the study. The exclusion criteria are any acute coronary syndrome within 3 months and failure to provide written informed consent. The patients are going to be randomized into 2 arms corresponding to 2 different strategies of CTO access approach. The intention was to include 400 patients with 200 patients in each group. All procedures are going to be performed by 3 interventional cardiologists at 3 different centers. The protocol was approved by the institutional review board and written informed consent is going to be provided by all patients.