Chronic total coronary occlusion

Coronary chronic total occlusions (CTO) make up 18% of all significant coronary lesions observed during diagnostic angiography, as demonstrated recently in a cohort study of 14, 400 angiographies from three Canadian centers. Sometimes, CTOs are detected when other coronary lesions progress and lead to unstable angina. For the left coronary artery (LCA), the guide catheter has to be selected according to the length of the left main artery, and the angle of take off of the occluded artery. Guidewire selection incorporates a great deal of personal preference and operator experience. Antegrade dissection can be achieved using a “knuckled” guidewire, but the reliability of the wire re-entry is not controllable. The retrograde approach proceeds by means of very structured steps, but it requires in all cases, except for an ostial occlusion, the positioning of an antegrade wire into the body of the occlusion. New types of complications occur through the application of the retrograde wire technique.