A multicenter registry study from the European CTO Club has revealed a remarkable 52% reduction (p<0.001) in radiation exposure for percutaneous coronary interventions (PCI) in chronic total occlusion (CTO) cases over 12 years. Despite increasing lesion complexity, improved procedural success and modernization of radiation management strategies have significantly lowered patient radiation exposure. The European CTO Club registry tracked CTO PCI procedures from 2012 to 2023, analyzing 16,439 cases performed by 14 expert operators. The primary objective was to assess trends in radiation exposure, measured by air kerma (AK), and determine factors influencing these changes.

Key findings include:

• Lesion complexity increased, with the median J-CTO score rising from 2 to 3 (p<0.001).
• Technical success rates improved from 89.1% to 94.9% (p<0.001).
• Radiation exposure (AK) decreased by 52%, from 2.50 Gy to 1.20 Gy (p<0.001).
• Excess radiation cases (AK >5 Gy) dropped from 15.8% to 3.7%.
• Operator efficiency improved, with a 21.7% reduction in the Dose Rate Index (DRI) even before equipment updates, reducing DRI by 28%.

Several factors drove the reduction in radiation exposure. Advances in fluoroscopy technology improved image quality while using lower doses, helping reduce radiation requirements. Further, operators became more skilled in using low-dose techniques. Additionally, adopting a hybrid procedural approach and increased use of intravascular ultrasound led to quicker, more precise interventions. Patient characteristics, such as body mass index and history of bypass surgery, were also considered to tailor procedures and minimize radiation exposure.

The findings highlight the feasibility of maintaining high procedural success while adhering to strict radiation safety standards. This significant drop in radiation exposure aligns with contemporary guidelines emphasizing patient safety, particularly avoiding AK >5 Gy to prevent deterministic radiation injuries. The data also underscore the variability in radiation management across operators, indicating a need for standardized protocols and continuous training. Implementing radiation safety programs and tracking dose metrics at institutional levels could enhance radiation protection.

While equipment modernization has played a critical role, the study emphasizes that operator expertise remains a crucial determinant of radiation exposure. Future research should explore additional strategies, including integrating artificial intelligence for real-time dose optimization, robotic-assisted PCI, and further refinement of imaging techniques. With growing emphasis on radiation safety, continued advancements in technology and technique are expected to drive further reductions in exposure, benefiting both patients and interventional cardiologists.

Reference:

Werner GS, Avran A, Boudou N, et al. Improvement of Radiation Management in Percutaneous Interventions of Chronic Total Occlusions in a Multicenter Registry. JACC Cardiovasc Interv. 2025;18(4):425-435. doi: 10.1016/j.jcin.2024.11.009. PMID: 40010913.