Background: Diagnostic reference level (DRL) was initially introduced by the International Commission on Radiological Protection, ICRP Publication 73 in 1996. The DRL has been proven to be an effective tool that aids in optimization of protection in the medical exposure of patients for diagnostic and interventional procedures. As the data on the cardiac procedures are limited, particularly in Southeast Asian region, the DRL in cardiac procedures has never been established in this region.

Materials and Methods: The survey in cardiac procedures covered 1,102 examinations from three procedures including coronary angiography (CAG), percutaneous coronary intervention (PCI), and permanent pacemaker (PPM) at 10 cardiac centers all over Thailand during 2019.

Results: For the CAG procedures, the DRLs of kerma area product (KAP) and air kerma (AK) were 29.3 Gycm² and 395 mGy, respectively. In PCI, DRLs for KAP and AK were 83.7 Gycm² and 1397 mGy respectively. For PPM, the DRLs of KAP and AK were 5.8 Gycm² and 59.0 mGy, respectively.

Conclusion: The present report is the first national DRLs on common cardiovascular procedures in Thailand. The results will help the optimization of patient dosages in the cardiac procedures in Thailand and in the neighboring countries, which can be used as the reference.

Keywords: Diagnostic reference level; Coronary angiography; Percutaneous coronary intervention

DOI: 10.35755/jmedassocthai.2022.09.13567

Received 25 October 2021 | Revised 14 July 2022 | Accepted 26 July 2022