Left main coronary artery bidirectional dissection caused by ejection of guideliner catheter from the guiding catheter.

The "Guideliner," a child catheter, aims to deliver stents in tortuous coronary lesions by deep engagement and providing better support. Coronary artery spiral dissection, which may be caused by deep-seated coronary catheters or noncoaxial engagement is one of the most seen percutaneous coronary intervention-related complications. In this case, Guideliner-related left main dissection occurred after successful revascularization of a chronic total occlusion at the left anterior descending artery and the left circumflex, which has not been previously reported. The Guideliner catheter is efficient in treating complex coronary lesions, but one should be aware of its related complications.