A Phantom Lesion in the Left Main Coronary Artery: Concertina Effect.

Classically described in tortuous coronaries, the concertina effect is a type of pseudostenosis induced by guidewire and is extremely rare in the left main coronary artery because of its short length. However, concertina effect in the left main coronary artery after percutaneous intervention should be considered in the appropriate setting to avoid confounding management dilemmas and unwarranted interventions.