The International Commission on Radiological Protection (ICRP) has established diagnostic reference levels (DRLs), which set benchmarks for limiting electromagnetic radiation doses across various procedures. This study reviewed DRLs based on dose report data for cardiovascular interventional procedures and analyzed patient electromagnetic radiation doses using Monte Carlo simulations and the High-Definition Reference Korean model, which is utilized as the voxel phantom. The procedures examined include coronary angiography (CAG), percutaneous coronary intervention (PCI), and percutaneous transluminal coronary angioplasty (PTCA). The diagnostic X-ray energy spectrum was generated using the SRS-78 program. Based on dose reports, the irradiation field was set to 13 × 13 cm², with tube voltages of 80 kVp, 100 kVp, and 120 kVp and exposure times of 243 seconds, 1043 seconds, and 1423 seconds, respectively. The source-to-image and source-to-skin distances were set to 120 cm and 84 cm, respectively. The NDD(K) method, an indirect dose calculation technique, was used to perform dose calculations and estimate absorbed doses across various organs. Subsequently, effective doses were calculated in accordance with the recommendations set in ICRP 60 and ICRP 103. The effective doses for CAG at 80 kVp and 100 kVp were found to be 1.47 mSv and 3.34 mSv, respectively. In PCI, the effective doses at 80 kVp, 100 kVp, and 120 kVp were 14.70 mSv, 9.52 mSv, and 16.00 mSv, respectively. For PTCA, the effective doses at 80 kVp, 100 kVp, and 120 kVp were observed to be 9.95 mSv, 24.16 mSv, and 32.83 mSv, respectively. Following the guidelines in ICRP 60 and ICRP 103, the conversion factors for effective dose ranged from 0.202 mSv/Gy·cm² to 0.418 mSv/Gy·cm² and from 0.213 mSv/Gy·cm² to 0.443 mSv/Gy·cm², respectively. These findings are expected to contribute to establishing optimal electromagnetic radiation exposure limits, promoting the safe management of medical electromagnetic radiation, and preventing excessive radiation exposure.