Radiation Exposure for Percutaneous Interventions of Chronic Total Coronary Occlusions in a Multicenter Registry: The Influence of Operator Variability and Technical Set-up

AIMS: Radiation exposure is a limiting factor for percutaneous coronary interventions (PCI) of chronic total coronary occlusion (CTO) lesions. This study was designed to analyze changes in patient radiation dose for CTO-PCI and parameters associated with radiation dose. METHODS AND RESULTS: We analyzed a cohort of 12,136 procedures performed by 23 operators between 2012 and 2017 from the European Registry of CTO-PCI. Radiation exposure was recorded as air kerma (AK) and dose area product (DAP). A dose rate index (DRI) was calculated as AK per fluoroscopy time to normalize for individual differences in fluoroscopy time. The lesion complexity increased from Japanese-CTO (J-CTO) score of 2.19 ± 1.44 to 2.46 ± 1.28, with an increase of retrograde procedures from 31.1% to 40.7%; still, procedural success improved from 87.7% to 92.1%. Fluoroscopy time remained similar, but AK decreased by 14.9%, from 2.35 Gy (interquartile range [IQR], 1.29-4.14 Gy) to 2.00 Gy (IQR, 1.08-3.45 Gy) and DAP decreased by 21.5%, from 130 Gy•cm² (IQR, 70-241 Gy•cm²) to 102 Gy•cm² (IQR, 58-184 Gy•cm²). Radiation exposure was determined by the lesion complexity (J-CTO score) and procedural complexity (antegrade or retrograde). DRI was determined by fluoroscopy frame rate and type of equipment used, but the major influence remained interoperator differences. CONCLUSIONS: Radiation exposure decreased during the observation period despite an increase in lesion and procedural complexity. While many operators already achieved a goal of low radiation exposure, there were considerable interoperator differences in radiation management, indicating further potential for improvement