Percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) is one of the greatest challenges in coronary interventions. A retrograde approach via the collateral channel has been recently proposed to improve the success rate of PCI in CTO lesions of the coronary arteries. We describe an accidental complication encountered during transradial PCI to recanalize right coronary artery CTO in a patient with unstable angina. A long spiral dissection has been created by antegrade wiring and extended from the ostium all the way down to mid RCA segment. Subsequent attempts with antegrade wiring into the true lumen were unsuccessful. Ad-hoc retrograde recanalization has been employed to rescue the vessel via septal collateral from left anterior descending artery. Retrograde wiring and dilatation were performed followed by successful antegrade wiring into the true lumen under IVUS guidance, which revealed significant intramural hematoma extending distally to the posterolateral branch. Bailout stenting was achieved with sealing of the multiple entry and exit sites created by the spiral dissection and complete coverage of the intramural hematoma. This report highlights the role of the retrograde approach as a rescue option in the setting of complicated antegrade approach and to improve the success rate of CTO-PCI. Moreover, IVUS was a valuable tool to confirm the true lumen course of the successful wire and to guide the stenting procedure. © 2012 Wiley Periodicals, Inc.