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Published on: August 11, 2015
Anatomy-Based Algorithm to Optimize Wiring Strategy After Primary Retrograde Approach in Short Chronic Total
Hidenari Matsumura1, Kenichiro Shimoji1
1Department of Cardiology, Saiseikai Utsunomiya Hospital, Utsunomiya, Japan.
Background:
The primary retrograde approach is an established strategy for chronic total occlusion (CTO), yet the optimal direction of wire advancement after successful channel crossing has not been systematically evaluated. In long CTOs, knuckle wiring and R-CART often facilitate lesion crossing, whereas in short CTOs, hematoma extension and limited R-CART points often hinder lesion crossing. We developed a novel algorithm for CTOs < 20 mm and validated it using the Japanese CTO Expert Registry.
Aims:
This study aimed to validate an algorithm for wire crossing after establishing the primary retrograde approach in short CTOs (< 20 mm).
Methods:
Registry data from 2014 to 2022 were analyzed. Among patients with CTOs < 20 mm treated by a primary retrograde approach with successful channel crossing, we excluded ostial CTOs, in-stent occlusions, tandem CTOs, unanalyzable caps, and anomalous origins, yielding 334 cases. Because the algorithm's first step states that "if both caps are tapered, either direction is acceptable," 130 such cases were excluded. The remaining 204 patients were classified as Algorithm-adherent or Algorithm-deviation. All lesion characteristics, exclusion criteria, and outcomes were adjudicated by an independent core laboratory.
Results:
Lesion guidewire manipulation time was significantly shorter in the Algorithm-adherent group (76.2 ± 48.9 vs. 123.2 ± 55.5 min; p < 0.0001). Total procedural time was also shorter in the Algorithm-adherent group (153.3 ± 64.2 vs. 205.0 ± 69.5 min, p < 0.0001), while procedural success rates were comparable between the two groups (99.2% vs. 95.9%, p = 0.13). These findings remained consistent after propensity score matching. No significant differences were observed in contrast volume or complication rates.
Conclusions:
The proposed algorithm for primary retrograde crossing of short CTOs was associated with shorter lesion guidewire manipulation and total procedural time, without compromising procedural success or safety.

