Real-Time IVUS-Guided Wiring With a Dual-Lumen Microcatheter for Blunt Proximal Cap CTO: Procedural Technique and Comparative Outcomes.

BACKGROUND: Percutaneous coronary intervention (PCI) for chronic total occlusions (CTOs) with blunt proximal caps is technically challenging due to unclear vessel morphology. Real-time intravascular ultrasound (IVUS) guidance can improve wire entry accuracy; however, its application with conventional pull-back IVUS systems remains underinvestigated. AIMS: To evaluate the feasibility and outcomes of real-time IVUS-guided wiring for blunt proximal cap CTO PCI. METHODS: We retrospectively analyzed patients who underwent PCI for blunt-cap CTOs between January 2020 and December 2024. Patients were categorized into IVUS-guided and angiography-guided wiring groups based on the initial strategy. The IVUS-guided approach employed a conventional pull-back IVUS system with a shaft-mounted transducer, advanced into a side branch, alongside a dual-lumen microcatheter positioned on the same wire to facilitate real-time imaging. In-hospital events and follow-up clinical outcomes were assessed. Overlap weighting based on propensity scores was applied to balance baseline and angiographic characteristics between groups. RESULTS: Of 152 patients, 17 underwent IVUS-guided wiring and 135 underwent angiography-guided wiring. The IVUS-guided group demonstrated reduced use of parallel wiring and retrograde techniques. Procedural success rates were high in both groups. Complete revascularization was numerically more frequent in the IVUS-guided group. Over 15.4 ± 6.9 months, the IVUS-guided group showed numerically lower rates of adverse clinical events, though the study was underpowered to detect definitive differences. CONCLUSIONS: Real-time IVUS-guided wiring using a conventional pull-back IVUS system with a dual-lumen microcatheter was feasible in selected blunt proximal cap CTO lesions. When a suitable side branch is available, this technique may offer a practical option for resolving proximal cap ambiguity.