Abstract

Introduction: Coronary artery disease is an important cause of morbidity and mortality which is a common cardiovascular disease and the clinical presentation of atherosclerosis. Coronary computed tomography angiography is increasingly being used instead of the invasive catheter angiography. We aimed to determine the effective radiation dose of retrospectively ECG gated and prospectively ECG triggered technique of coronary computed tomography angiography for the assessment of coronary artery diseases.
Materials and Methods: Three hundred and twenty six patients who underwent coronary computed tomography angiography were evaluated by using a 256 slice dual source scanner. We have used 3 different techniques depended to the heart rate of patients and compared the effective radiation dose between the techniques in our study.
Results: The mean heart rates was demonstrated as 96,1 beat/minute in 195 patients with technique I, 80,7 beat/minute in 103 patients with technique II and 57,1 beat/minute in 28 patients with technique III. Also, the mean effective doses were calculated as 1,15 mSv in technique I, 3,98 mSv in in technique II and 10 mSv technique III.
Conclusion: Prospectively ECG-triggered coronary computed tomography angiography ensures low effective radiation dose compared with retrospectively ECG gated for assessment of coronary artery diseases. Depended to the heart rate of the patient, the appropriate technique should be determined to obtain low radiation dose and an optimal image quality.

Key words: Coronary CT Angiography; Radiation Dose; 256-Slice Dual Source CT Scanner.