Establishing a diagnostic reference level of radiation dose in coronary angiography and intervention: A prospective evaluation

INTRODUCTION: Invasive Coronary Angiography (CAG) leads to significant radiation exposure to the patients. Guidelines suggest that a local landmark or Diagnostic Reference Level (DRL) for these procedures should be established for every region and country. This study attempts to create a DRL for a tertiary care hospital, acting as an interim DRL for the country/region. METHODS: Radiation exposure data for all coronary procedures done at a tertiary care hospital between October 2016 to September 2018 were collected. Data was segregated into diagnostic Coronary Angiography (CAG) and single-vessel Percutaneous Intervention (PCI). The parameters collected include dose surface product (P(KA)), skin surface entry dose (K(AR)), and fluoroscopy time (FT). The 75th percentile of the P(KA) was used to define the DRL. RESULTS: 500 Patients were included in the CAG group, in which the Median K(AR) was 412.05 mGy, Median P(KA) was 2635.7 μGysqm, and median FT was 2.25 min. The DRL for coronary angiography was calculated as 3695.1 μGysqm. Two hundred fifty patients were in the PCI group, the Median K(AR) was 1649 mGy, Median P(KA) was 8822.1 μGysqm, the median FT being 8.2 min. The DRL for single-vessel coronary intervention was calculated as 11038 μGysqm. CONCLUSION: This study establishes a benchmark for radiation dose for diagnostic coronary angiography and single-vessel coronary intervention at a tertiary care hospital in NCR. It establishes an interim DRL that can be used for future studies in other institutions in the region and country and to compare with other countries.