An update on coronary artery chronic total occlusions.

A coronary artery chronic total occlusion (CTO) represents a coronary artery that has been occluded for a long period of time, typically months. Coronary artery CTOs are common and occur in approximately one-third of patients referred for coronary angiography. Revascularization of CTO is technically challenging and has historically been associated with lower procedural success rates and higher complication rates. Technical success of CTO revascularization has significantly improved given remarkable advances in interventional cardiology over the past 3 decades. However, the decision to perform CTO revascularization remains a dilemma, given the lack of robust clinical evidence to support its use.