Coronary chronic total occlusions: How to dilate the tough ones.

Several chronic total occlusions (CTOs) may be undilatable despite successful wire passage; several techniques can be used for lesion preparation, such as high-pressure balloon inflations, rotational atherectomy laser, cutting balloon, and scoring balloons. Presence of moderate to severe calcification and lesion length over 40 mm in association with comorbidities, such as diabetes mellitus and reduced ejection fraction, may contribute to making a CTO lesion undilatable. Still, appropriate therapy selection for a patient with CTO should be individualized and procedure safety attended to.