RESUMO
Objective To explore the feasibility of low-tube-voltage and low-concentration contrast agent applied to coronary computed tomography angiography (CTA) in the overweight patients. Methods Totally 83 overweight patients with suspected coronary heart disease who underwent coronary artery angiography were randomly assigned into two groups. Group A used 100 kVp and ioversol-320 mg/ml, and Group B received 120 kVp and iopamidol-370 mg/ml. Both the groups went through prospectively ECG-gated scanning. The two groups were compared on the image quality, radiation dose, iodine intake and coronary artery segments scores. Results The effective radiation dose and iodine intake in Group A were significantly lower than those in Group B (P<0.05). Group A had the coronary artery CT value and image noise lower significantly than Group B (P<0.05). No significant differences in signal to noise ratio, contrast to noise ratio and coronary artery segments scores were observed between the two groups (P>0.05). Conclusion For coronary artery CTA in the overweight patients, low-tube-voltage and low-concentration contrast agent still preserves the image quality, as well as significantly reduces the radiation dose and iodine intake.