CHRONIC TOTAL OCCLUSIONS OF THE CORONARY ARTERIES: CURRENT OPPORTUNITIES AND CHALLENGES IN INTERVENTIONAL TREATMENT

Highlights

• Percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) is an effective treatment option for patients with refractory angina, contributing to improved quality of life and reduction of ischemic symptoms, provided that patient selection and procedural planning are carefully performed.
• Preprocedural planning, including dual-contrast angiography, coronary computed tomography angiography, and the use of validated scoring systems (J-CTO, PROGRESS-CTO, CT-RECTOR), plays a critical role in selecting the optimal interventional strategy and minimizing the risk of complications.
• An algorithmic approach and multidisciplinary collaboration enhance the success and safety of CTO PCI, particularly when hybrid and global strategies are employed and tailored to the anatomical features of the lesion.

Abstract

Chronic total occlusions of the coronary arteries (CTO) represent one of the most complex forms of coronary artery disease, occurring in approximately 15–20% of patients with ischemic heart disease undergoing coronary angiography. Despite the long-standing absence of a unified treatment strategy, the interventional approach to CTO has undergone significant transformation in recent decades. This evolution is largely driven by advancements in imaging technologies, improvements in guidewire and catheter systems, and the implementation of algorithmic decision-making in procedural planning. Percutaneous coronary intervention (PCI) for CTO enables effective relief of anginal symptoms, improvement in quality of life, and enhancement of functional status, while minimizing the risk of serious complications. A critical factor in procedural success is thorough preprocedural planning, which includes dual-injection coronary angiography, coronary computed tomography angiography (CTCA), and assessment of anatomical complexity using scores such as J-CTO, PROGRESS-CTO, and CT-RECTOR. The use of hybrid and global CTO management algorithms, tailored to lesion morphology, facilitates individualized strategies and improves procedural outcomes. Operator experience, availability of dedicated equipment, and cohesive team coordination are also pivotal to clinical success. This review summarizes current approaches to the diagnosis, planning, and execution of PCI in CTO cases, emphasizing the importance of a multidisciplinary approach and the role of advanced imaging modalities in enhancing the safety and efficacy of interventional treatment.

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