title: 128-slice Dual-source Computed Tomography Coronary Angiography in Patients with Atrial Fibrillation: Image Quality and Radiation Dose of Prospectively Electrocardiogram-triggered Sequential Scan Compared with Retrospectively Electrocardiogram-gated Spiral Scan.
abstract: Objective To evaluate the image quality (IQ) and radiation dose of 128-slice dual-source computed tomography (DSCT) coronary angiography using prospectively electrocardiogram (ECG)-triggered sequential scan mode compared with ECG-gated spiral scan mode in a population with atrial fibrillation. Methods Thirty-two patients with suspected coronary artery disease and permanent atrial fibrillation referred for a second-generation 128-slice DSCT coronary angiography were included in the prospective study. Of them, 17 patients (sequential group) were randomly selected to use a prospectively ECG-triggered sequential scan, while the other 15 patients (spiral group) used a retrospectively ECG-gated spiral scan. The IQ was assessed by two readers independently, using a four-point grading scale from excel-lent (grade 1) to non-assessable (grade 4), based on the American Heart Association 15-segment model. IQ of each segment and effective dose of each patient were compared between the two groups. Results The mean heart rate (HR) of the sequential group was 96±27 beats per minute (bpm) with a variation range of 73±25 bpm, while the mean HR of the spiral group was 86±22 bpm with a variationrange of 65±24 bpm. Both of the mean HR (t=1.91, P=0.243) and HR variation range (t=0.950, P=0.350) had no significant difference between the two groups. In per-segment analysis, IQ of the sequential group vs. spiral group was rated as excellent (grade 1) in 190/244 (78%) vs. 177/217 (82%) by reader1 and 197/245 (80%) vs. 174/214 (81%) by reader2, as non-assessable (grade 4) in 4/244 (2%) vs. 2/217 (1%) by reader1 and 6/245 (2%) vs. 4/214 (2%) by reader2. Overall averaged IQ per-patient in the sequential and spiral group showed equally good (1.27±0.19 vs. 1.25±0.22, Z=-0.834, P=0.404). The effective radiation dose of the sequential group reduced significantly compared with the spiral group (4.88±1.77 mSv vs. 10.20±3.64 mSv; t=-5.372, P=0.000). Conclusion Compared with retrospectively ECG-gated spiral scan, prospectively ECG-triggered sequential DSCT coronary angiography provides similarly diagnostically valuable images in patients with atrial fibrillation and significantly reduces radiation dose.
authors.affiliation: Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Lin
authors.forename: Yi-Ning
authors.initials: YN
authors.lastname: Wang
authors.forename: Ling-Yan
authors.initials: LY
authors.lastname: Kong
authors.forename: Zheng-Yu
authors.initials: ZY
authors.lastname: Jin
authors.forename: Guang-Ming
authors.initials: GM
authors.lastname: Lu
authors.forename: Zhao-Qi
authors.initials: ZQ
authors.lastname: Zhang
authors.forename: Jian
authors.initials: J
authors.lastname: Cao
authors.forename: Shuo
authors.initials: S
authors.lastname: Li
authors.forename: Lan
authors.initials: L
authors.lastname: Song
authors.forename: Zhi-Wei
authors.initials: ZW
authors.lastname: Wang
authors.forename: Kang
authors.initials: K
authors.lastname: Zhou
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
mesh_terms: D001281:Atrial Fibrillation; D017023:Coronary Angiography; D004562:Electrocardiography; D006801:Humans; D011446:Prospective Studies; D011829:Radiation Dosage; D036542:Tomography, Spiral Computed