National survey to update the Italian diagnostic reference levels in interventional cardiology

The Italian National Institute of Health, in collaboration with national scientific societies, coordinated a multicenter survey to update Diagnostic Reference Levels (DRLs) for interventional cardiology across Italy. Regular revision of DRLs is essential to reflect technological advances and procedural optimization. Using an established methodology, anonymized patient, procedural, and equipment data were collected from 40 representative centers across 14 Italian regions.

This is a restrospective observational study. The survey focused on six major interventional cardiology procedures in adult patients: coronary angiography (CA), CA with percutaneous coronary intervention (CA + PCI), transcatheter aortic valve implantation (TAVI), pacemaker implantation and cardiac implantable device (PM/ICD), radiofrequency ablation (RFA), and electrophysiological studies (EPS). For each procedure, radiation dose metrics-including Kerma Area Product (P_KA), cumulative Air Kerma, and fluoroscopy time-were collected. Patient-related factors (age range, weight, BMI, etc.), clinical and technical parameters were also recorded and procedures were classified according to type and complexity.

A total of 6363 procedures were analyzed. National DRLs were derived as the 75th percentile of the median values from individual centers and compared with international benchmarks. A multivariable analysis of P_KA was performed to identify clinical and procedural factors significantly influencing patient radiation exposure and to establish complexity-stratified DRLs.

Updated DRL values were defined for all six procedures: 38 Gy·cm² for CA, 89 Gy·cm² for CA + PCI, 184 Gy·cm² for TAVI, 11 Gy·cm² for PM, 18 Gy·cm² for RFA, and 12 Gy·cm² for EPS. Complexity-specific DRLs were also established for CA + PCI, PM, and RFA, providing guidance for optimizing patient radiation exposure in interventional cardiology practice.