Chronic total occlusion (CTO) is defined as the complete obstruction of coronary arteries in the duration of at least three months. In the last two decades interest in new techniques of percutaneous treatment of chronic total occlusion has increased and it has shown a greater rate of successful treatment compared to before.1 Thanks to the new materials and techniques used in chronic total occlusion percutaneous coronary intervention (CTO PCI) the blood vessels can be opened in a higher percentage and even more importantly, the patient’s life quality is improved and mortality decreased. However, all scientific evidence backing this treatment come from observational studies, but a randomized controlled trial to compare the outcome of treatment of patients before and after CTO PCI has not yet been conducted. The main issue with this intervention is problematic visualization (flying blind), difficult passage of dilatation wire, length of procedure and high costs of material necessary for this intervention, as well as limited information considering the potential basic differences between successful and unsuccessful groups