Application of low tube voltage coronary CT angiography with low-dose iodine contrast agent in patients with a BMI of 26-30Â kg/m2

•We use CCTA with low tube voltage and iodine dose for overweight patients.•Low tube voltage, Iodixanol and AIDR were used in double low protocol.•The double low protocol provided low CTDIvol, DLP, ED, and iodine intake.•The double low protocol also provided images of diagnostic quality.

AimTo evaluate the feasibility of using a reduced radiation dose and reduced iodine intake (i.e., “double low”: low tube voltage/low iodine dose contrast agent) scanning protocol and the adaptive iterative dose reduction (AIDR) reconstruction algorithm in coronary heart disease (CHD) patients with a BMI of 26-30 kg/m2.Materials and methodsOne-hundred and seventy-nine consecutive CHD patients with a body mass index >26 kg/m² but <30 kg/m² were randomly assigned to two groups (group A: 53 men, 39 women, average age 61.83 ± 11.84 years, and group B: 40 men, 47 women, average age 62.25 ± 11.37 years) based on tube voltage, contrast agent, and algorithm used. Group A underwent the “double low” protocol (iodixanol at 270 mg iodine/ml, 100 kVp tube voltage, and AIDR). Group B received the conventional protocol [iopamidol at 370 mg iodine/ml, 120 kVp tube voltage, and filtered back projection (FBP)].ResultsThe volume CT dose index (CTDIvol), dose-length product (DLP), effective dose (ED), and iodine intake of patients in “double low” group A were significantly lower than the “conventional” group B (p < 0.001). The mean intraluminal attenuation and contrast enhancement in group A were also significantly less than group B (p < 0.001), whereas the image noise using AIDR in group A was significantly lower than group B using FBP (p < 0.001). However, the signal-to- noise ratio (SNR), contrast-to-noise ratio (CNR), and image-quality scores between the two groups were comparable.ConclusionsUse of 320-row CT with a “double low” scanning protocol for CCTA in patients with a BMI of 26-30 kg/m2 not only provided images of diagnostic quality but also reduced both radiation dose and iodine intake during scanning.