Improvement of Radiation Management in Percutaneous Interventions of Chronic Total Occlusions in a Multicenter...

Excess radiation exposure is a limiting factor in percutaneous coronary intervention (PCI) for chronic total coronary occlusion (CTO).

The aim of this study was to analyze changes in radiation dose for CTO PCI with increasing risk awareness during the past decade and the determinants of these changes.

A total of 16,439 procedures performed by 14 operators continuously participating in the European Registry of CTO-PCI from 2012 to 2023 were analyzed. Changes in air kerma (AK) were assessed, and a dose rate index (DRI) was calculated as AK per fluoroscopy time (FT).

Lesion complexity increased from a median J-CTO (Multicenter CTO Registry in Japan) score of 2 (Q1-Q3: 1-3) to 3 (Q1-Q3: 2-3) (P < 0.001), and technical success improved from 89.1% to 94.9% (P < 0.001), with stable FT. AK decreased from 2.50 Gy (Q1-Q3: 1.54-4.04 Gy) to 1.20 Gy (Q1-Q3: 0.66-2.12 Gy), a reduction of 52.0% (P < 0.001). Excess radiation of AK >5 Gy was reduced from 15.8% in 2012-2013 to 3.7% in 2022-2023. Clinical determinants of excess radiation were body mass index, gender, and previous bypass surgery; procedural determinants were FT, retrograde approach, and intravascular ultrasound use; and equipment determinants were radiographic equipment updates and fluoroscopy dose mode. Operators reduced DRI by 21.7% from 62.6 mGy/min (Q1-Q3: 44.7-89.3 mGy/min) to 49.0 mGy/min (Q1-Q3: 35.4-71.2 mGy/min) before a radiographic equipment update; after the update, DRI was further reduced to 31.5 mGy/min (Q1-Q3: 22.0-45.6 mGy/min), a decrease of 28.0% (P < 0.001) The interoperator comparison of DRI indicated considerable variability in radiation management.

AK for CTO PCI was reduced during the past decade to a level such that most procedures no longer must be aborted because of excess radiation. Equipment updates were instrumental, but interoperator differences remained.