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Background: The number of interventional cardiology (IC) procedures has increased rapidly. coronary angiography (CA) and percutaneous transluminal coronary angioplasty (PTCA) are now widely performed as a matter of routine, and they are considered safe procedures for experienced cardiologists. However, it is also known that these procedures are associated with high radiation doses due to long fluoroscopy time (T), and large number of cineradiography frames (F). These levels of radiation may even lead to radiation skin injuries under certain conditions. Materials and Methods: A detailed study of radiation doses received by 168 patients who underwent coronary angiography (CA), and 84 patients who underwent percutaneous transluminal coronary angioplasty (PTCA) using 3 angiography X-ray systems in two hospitals of Yazd-Iran is presented. An air kerma-area product (KAP) meter was used for patient dosimetry. KAP, fluoroscopy time and total number cine frames for CA and PTCA procedures were recorded for each patient. Results: Mean ± SD of KAP in CA and PTCA were 33 Gy.cm2 ± 18.8 Gy.cm2 and 80.3 Gy.cm2 ± 65.6 Gy.cm2 respectively. The comparison showed that CA KAP (33Gy.cm2), fluoroscopy time (2.7±2.4min), and cine frames number (571±149) except of on case, were lower than (P<0.001) the results of other studies and mean KAP due to PTCA procedures, except for three cases, were not significatly different from the other references’ results. Conclusion: The high level expert cardiologists couldn't have a significant effect on the decrease of patient dose since they should also teach angiography examinations to medicine students. With increasing patient BMI the value of KAP increased, but the fluoroscopy time and cineframes number did not change significantly. In addition, the results showed that the use of flat panel detector was not sufficient for decreasing patient dose, and system's adjustment was more important. Iran. J. Radiat. Res., 2009 6 (4): 167-172