This document discusses strategies and techniques for managing chronic total occlusions (CTO). CTOs are coronary blockages that are completely blocked for more than 3 months. The document outlines the histopathology of CTOs and factors that predict success or failure of percutaneous coronary intervention (PCI). It also describes various guidewires, microcatheters, and crossing devices that can be used to recanalize CTOs via antegrade or retrograde approaches. Successful PCI of CTOs has been shown to improve angina, reduce the need for bypass surgery, and improve survival.