ABSTRACT
This chapter focuses on the retrograde approach for the percutaneous revascularization of chronic total occlusions (CTOs), provides an overview of some basic knowledge about coronary collateral channels, as well as the relevant histopathological features of CTOs. The retrograde approach requires a channel between the occluded coronary artery and another patent coronary artery, which enables the distal CTO site to be reached in a retrograde way. Retrograde wire recanalization technique uses a retrograde approach with a single wire, without simultaneous antegrade approach. The CTO is crossed only in a retrograde manner. Kissing wire technique combines the simultaneous use of antegrade and retrograde approaches. The retrograde wire serves either as a marker of the distal CTO location or creates an intraluminal channel in the distal CTO portion. The retrograde approach requires an intercoronary channel, which can be either an epicardial collateral, a septal collateral, or a bypass graft.
