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Chronic total occlusion of coronary artery — Clinical Guidelines

Overview

Chronic total occlusion (CTO) of coronary arteries involves complete blockage of a coronary artery lasting more than three months, often necessitating complex percutaneous coronary intervention (PCI) techniques for revascularization. 1 7

Diagnosis

Angiography is essential for identifying CTO, assessing occlusion length, and evaluating collateral circulation.

The J-CTO score can predict procedural feasibility and guidewire crossing time, particularly useful for both de novo and in-stent CTOs. 2

High-resolution imaging techniques like intravascular ultrasound (IVUS) can aid in navigating guidewires and assessing lesion characteristics. 13 15

Management

Primary Techniques: Antegrade wire crossing, subintimal tracking and reentry (STAR technique), and retrograde approaches are commonly used. 1 7 14

Advanced Tools: Use of specialized devices such as Stingray for antegrade dissection, CrossBoss/Stingray for reentry, and advanced guidewires like those evaluated in the G-FORCE study for antegrade crossing. 7 11

Stenting Strategies: Overlapping stents versus single long stents for long CTOs; contemporary registries suggest both strategies have comparable outcomes. 4

Radiation Management: Utilization of dose-reducing fluoroscopic systems to minimize patient radiation exposure without compromising procedural success. 5

Special Populations

Elderly Patients: No specific guidelines provided in abstracts; procedural complexity and patient comorbidities should be carefully considered. 6

Comorbidities: Management strategies remain largely similar across different comorbidities, though procedural complexity may vary. 6

Key Recommendations

Utilize the J-CTO score to assess procedural feasibility and predict guidewire crossing time in CTO PCI procedures. (Evidence: Moderate) 2

Employ advanced imaging techniques like IVUS to enhance navigation and guidewire placement during CTO interventions. (Evidence: Moderate) 13 15

Consider dose-reducing fluoroscopic systems to minimize patient radiation exposure during CTO PCI without compromising procedural success. (Evidence: Moderate) 5

Select stenting strategies (overlapping vs. single long stents) based on lesion length and operator preference, as both show comparable clinical outcomes. (Evidence: Moderate) 4

Incorporate specialized devices such as Stingray and CrossBoss/Stingray for complex reentry scenarios to improve procedural success rates. (Evidence: Moderate) 7 11

References

1 Frizzell JD, Kane JA, Hirai T. From Poser to Pro: Navigating the Subintimal Space and Managing Hematoma. Interventional cardiology clinics 2026. link 2 Chen CY, Huang CH, Cheng JF, Lee CL, Chiang JY, Liu SC et al.. Application of the J-CTO Score to Recanalization for In-Stent Chronic Total Occlusions. The American journal of cardiology 2026. link 3 Zhou C, Cao YZ, Jia ZY, Zhao LB, Lu SS, Xu XQ et al.. Radiological features on high-resolution MR imaging predicts successful recanalization in patients with symptomatic chronic intracranial large artery occlusion. Academic radiology 2025. link 4 Jurado-Román A, Miñana G, Salinas P, Regueiro A, Caballero-Borrego J, Martín-Moreiras J et al.. Overlapping versus single long stents in long chronic total occlusions: insights of the Iberian CTO Registry. Minerva cardiology and angiology 2023. link 5 Salinas P, Sanchez-Casanueva RM, Gonzalo N, A Gil J, Salazar CH, Jimenez-Quevedo P et al.. Dose-reducing fluoroscopic system decreases patient but not occupational radiation exposure in chronic total occlusion intervention. Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions 2021. link 6 Eertmans W, Kayaert P, Bennett J, Ungureanu C, Bataille Y, Saad G et al.. The evolution of the CTO-PCI landscape in Belgium and Luxembourg: a four-year appraisal. Acta cardiologica 2021. link 7 Wu EB, Brilakis ES, Lo S, Kalyanasundaram A, Mashayekhi K, Kao HL et al.. Advances in CrossBoss/Stingray use in antegrade dissection reentry from the Asia Pacific Chronic Total Occlusion Club. Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions 2020. link 8 Roy J, Hill J, Spratt JC. The "side-BASE technique": Combined side branch anchor balloon and balloon assisted sub-intimal entry to resolve ambiguous proximal cap chronic total occlusions. Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions 2018. link 9 Nihei T, Yamamoto Y, Kudo S, Hanawa K, Hasebe Y, Takagi Y et al.. Impact of the Intracoronary Rendezvous technique on coronary angioplasty for chronic total occlusion. Cardiovascular intervention and therapeutics 2017. link 10 Xue J, Li J, Wang H, Sheng L, Gong Y, Sun D et al.. "Seesaw balloon-wire cutting" technique is superior to Tornus catheter in balloon uncrossable chronic total occlusions. International journal of cardiology 2017. link 11 Ikari Y, Awata M, Mitsudo K, Akasaka T, Saito S, Ishihara T et al.. Efficient distal tip size of primary guidewire for antegrade percutaneous coronary intervention in chronic total occlusion: The G-FORCE study. International journal of cardiology 2017. link 12 Carlino M, Figini F, Ruparelia N, Uretsky BF, Godino C, Latib A et al.. Predictors of restenosis following contemporary subintimal tracking and reentry technique: The importance of final TIMI flow grade. Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions 2016. link 13 Okamura A, Iwakura K, Date M, Nagai H, Sumiyoshi A, Fujii K. Navifocus WR is the promising intravascular ultrasound for navigating the guidewire into true lumen during the coronary intervention for chronic total occlusion. Cardiovascular intervention and therapeutics 2014. link 14 Muramatsu T, Tsukahara R, Ito Y, Ishimori H, Park SJ, de Winter R et al.. Changing strategies of the retrograde approach for chronic total occlusion during the past 7 years. Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions 2013. link 15 Park Y, Park HS, Jang GL, Lee DY, Lee H, Lee JH et al.. Intravascular ultrasound guided recanalization of stumpless chronic total occlusion. International journal of cardiology 2011. link 16 Furuichi S, Airoldi F, Colombo A. Intravascular ultrasound-guided wiring for chronic total occlusion. Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions 2007. link

Chronic total occlusion of coronary artery