The first clinical experience with a novel "locking" microcatheter in chronic coronary total occlusions.

AIMS: A novel "locking" microcatheter has been developed to address residual failure modes in chronic total occlusion (CTO) percutaneous coronary intervention (PCI). The aim of this study was to report the first clinical experience of this device.

METHODS AND RESULTS: The microcatheter was assessed prospectively in 92 unselected CTO cases across six European sites. Overall technical success was 85.9% (79/92) and 97.5% for patients with a J-CTO score of <3 (39/40). Within-CTO tortuosity was the only lesion characteristic to predict reduced technical success (OR 0.10 [0.01-0.97], p=0.047). Calcification (OR 0.45 [0.04-5.31], p=0.53), lesion length >20 mm (OR 0.58 [0.05-6.81], p=0.66) and a blunt proximal cap (OR 0.47 [0.08-2.90], p=0.42) were not associated with technical failure in this case series. Locking facilitated guidewire crossing (after initial failure) of the proximal cap in 23 cases, distal cap in 11 cases and CTO body in 10 cases, and delivery of the microcatheter through to the distal vessel in 22 cases. The overall procedural complication rate was 1.1% (1/92) with no major events.

CONCLUSIONS: Guidewire locking with this novel microcatheter assists penetration and crossing of fibrocalcific anatomy with a high degree of safety. Using this device in CTO PCI may lead to improved primary wiring and overall procedural success rates.