The DELIVER Technique: A Comprehensive Review of Deep Catheter Engagement for Rotational Atherectomy in Complex Coronary Anatomy

Rotational Atherectomy (RA) is an essential technique for managing severely calcified coronary artery disease during percutaneous coronary intervention. However, burr delivery can be significantly hindered in patients with complex anatomy, such as proximal vessel tortuosity, previously implanted stents, transcatheter aortic valves, or anomalous coronary origins. These anatomical limitations elevate the risk of procedural failure and severe complications, including burr entrapment, burr fracture, coronary artery perforation, and dissection. The DELIVER technique— Deep Engagement of guide catheter or chiLd-guIde catheter for burr deliVEry and Rotational atherectomy—was developed to overcome these challenges through strategic deep catheter positioning using dedicated advancement techniques. This mini-review provides an in-depth exploration of the DELIVER technique, including clinical rationale, procedural steps, device selection, anatomical considerations, safety strategies, and comparative performance with other calcium modification methods. Recent evidence and procedural experience suggest that the DELIVER technique offers an effective and versatile solution for improving procedural success in RA for anatomically complex cases.