Dual‐Lumen Microcatheters in Percutaneous Coronary Intervention: Five Useful Techniques to Facilitate Coronary Wiring in Non‐CTO Lesions

BACKGROUND: Dual-lumen microcatheters (DLMs) are adjunctive devices that has been increasingly incorporated into contemporary percutaneous coronary intervention (PCI). These catheters contain two independent working lumens, a rapid-exchange (RX) port and an over-the-wire (OTW) port, within a single low-profile shaft, permitting guidewire advancement and exchange within a shared working space. Published consensus documents have focused predominantly on chronic total occlusion (CTO) lesions, with less on non-CTO lesions. METHODS: This narrative review describes five practical applications of DLMs in non-CTO lesions. For each technique, we outlined the procedural rationale, a stepwise approach, and technical considerations. RESULTS: Five applications are presented: (1) aorto-ostial wiring in the setting of a protruding ostial stent or anomalous coronary takeoff; (2) reverse wiring of a side branch with an acute or angulated takeoff; (3) side-branch re-entry after stent deployment; (4) contrast injection through the OTW port; and (5) parallel wiring for complex lesions. CONCLUSIONS: DLMs offer several practical applications beyond CTO PCI. Familiarity with these techniques and their technical considerations may help operators select and apply DLM-assisted strategies in complex non-CTO lesions.