<p>Incidence, Predictors, and Strategies for Failure of Retrograde Microcatheter Tracking After Successful Wiring of Septal Collateral Channels in Chronic Total Occlusions</p>

Abstract

Background: Retrograde microcatheter collateral channel (CC) tracking after successful wiring of septal CC is crucial for retrograde revascularization of coronary chronic total occlusion (CTO). However, the incidence, predictors, and strategies for failure of retrograde microcatheter CC tracking after successful wiring of septal CC remain unclear. Methods: In total, 298 patients with CTO who underwent retrograde septal CC PCI between January 2015 and May 2019 were retrospectively analyzed. Clinical data were compared to investigate the predictors of initial microcatheter tracking failure. Results: The initial and final microcatheter tracking success rates were 79.2% (236/298) and 96.6% (288/298), respectively. The procedural success rate was 94.0% (280/298). The right coronary artery-to-left anterior descending artery septal ratio (48.4% vs 33.1%, p=0.037) and CC tortuosity (34.6% vs 20.8%, p=0.045) were significantly higher in the initial microcatheter CC tracking failure group than in the successful tracking group. Multivariate logistic regression analysis revealed that severe collateral tortuosity (odds ratio [OR]: 13.241, 95% confidence interval [CI]: 3.429-27.057, p=0.038), CC entry angle of <90° (OR:4.921, 95% CI: 1.128-9.997, p=0.002), CC exit angle of <90° (OR:5.037, 95% CI: 2.237-11.182, p=0.004), use of Finecross MG as initial microcatheter (OR:1.826, 95% CI: 1.127-3.067, p=0.035), and shunning initial retrograde application of Guidezilla (OR:0.321, 95% CI: 0.267-0.915, p=0.024) were variables independently associated with initial microcatheter CC tracking failure in patients with CTO undergoing retrograde septal CC PCI. Conclusion: The overall initial microcatheter CC tracking failure was 20.8%. Severecollateral tortuosity, CC entry, and exit angle of <90°, use of Finecross MG as initial microcatheter, and shunning initial retrograde application of Guidezilla were variables independently associated with initial microcatheter CC tracking failure in patients with CTO undergoing retrograde septal PCI.

Applicability of J‐CTO channel score to predict microcatheter tracking during retrograde percutaneous coronary intervention of chronic total occlusions: Insights from the SURFING MICRO registry

“…In our study, dedicated microcatheters such as Corsair Pro, Corsair Pro XS, Caravel, Turnpike LP and Mamba Flex were used for initial microcatheter tracking compared to the Zhong et al in which Finecross was the initial microcatheter in most cases of switching (Supporting Information: Table ). Moreover, in one study, the use of the Finecross was an independent predictor of MTF during retrograde CTO PCI 14 . Recently, Ioppolo et al 15 have investigated angiographic predictors of septal tracking and found that small size and length of collaterals were an independent predictors of MTF.…”

“…Moreover, in one study, the use of the Finecross was an independent predictor of MTF during retrograde CTO PCI. 14 Recently, Ioppolo et al 15 have investigated angiographic predictors of septal tracking and found that small size and length of collaterals were an independent predictors of MTF. At the same time, small size, tortuosity, and exit angle <90°were predictors for guidewire tracking failure, proposing the new R-ICPS score ("retrograde-interventional collateral predictor score") to predict CC crossing.…”

Scoring system related to retrograde percutaneous coronary intervention for coronary chronic total occlusion

“…A study that included 371 consecutive retrograde CTO‐PCI procedures between March 2015 and January 2018 revealed that CCs entry, and exit angle of <90° were independently related to initial microcatheter CCs tracking failure for septal CCs [27]. And another study retrospectively analyzed 298 patients with CTO who underwent retrograde septal CCs PCI between January 2015 and May 2019 also demonstrated that CCs entry, and exit angle of <90° were variables independently associated with initial microcatheter CCs tracking failure in patients with CTO undergoing retrograde septal PCI [28]. Another controversial issue was whether retrograde CTO‐PCI should be the initial or secondary strategy.…”

“…Then, a study by Wang et al. [25] suggested that the success rate of retrograde guidewires tracking via poor septal CCs (Werner's CC0–1) was high, with a relatively high procedural success rate. They revealed that a CC diameter <1 mm, well‐developed non‐septal collateral, and LAD‐CTO were independent predictors of guidewire tracking failure in patients undergoing retrograde CTO‐PCI via poor septal CCs.…”

Prevalence, predictors, and management for balloon uncrossable or undilatable lesions in patients undergoing percutaneous coronary intervention with in-stent restenosis chronic total occlusion

“…A multiple guidewire technique and balloon anchoring technique are other options for stronger support. A corsair microcatheter with a micro-expansion function is preferable to improve the success rate of the intervention ( 20 ). High-pressure balloon inflations are typically used for BUs.…”