Hideaki Yuki MD, Presenter: Nothing to Disclose

Seitaro Oda MD, Abstract Co-Author: Nothing to Disclose

Keiichi Honda, Abstract Co-Author: Nothing to Disclose

Akira Yoshimura, Abstract Co-Author: Nothing to Disclose

Kazuhiro Katahira, Abstract Co-Author: Nothing to Disclose

Yasuyuki Yamashita MD, Abstract Co-Author: Consultant, DAIICHI SANKYO Group

Daisuke Utsunomiya MD, Abstract Co-Author: Nothing to Disclose

Tomohiro Namimoto MD, Abstract Co-Author: Nothing to Disclose

Takeshi Nakaura MD, Abstract Co-Author: Nothing to Disclose

Kenichiro Hirata, Abstract Co-Author: Nothing to Disclose

Masafumi Kidoh, Abstract Co-Author: Nothing to Disclose

The purpose of this study was to assess the optimal reconstruction phase and the image quality of coronary CT angiographs obtained on a 256-slice CT scanner in patients with atrial fibrillation (AF).

We acquired 256-slice coronary CT angiographs of 60 consecutive patients with AF (45 men and 15 women; age 72.1 ± 8.1 years) and 60 controls (43 men and 17 women; age 67.1 ± 9.9 years) in sinus rhythm. The images were reconstructed in 2% steps in all parts of the cardiac cycle (R-R interval). Two experienced radiologists determined the optimal reconstruction phase with the fewest motion artifacts and scored the motion artifacts of each coronary artery segment to determine the ability to assess each segment. Pearson’s correlation analysis was performed to compare the quality of images obtained at the mean heart rate (HR) of the controls and under conditions of HR variability in the AF patients.

The average HR and the HR variability during scanning were 70.3 bpm ± 15.9 and 15.4 bpm ± 6.9 in the AF patients; 60.1 bpm ± 12.9 and 1.4 bpm ± 1.1in the controls. There was a significant difference in the average and the variable HR. In 45 of the 60 AF patients (75%), the optimal reconstruction phase window was the end-diastolic phase (90-99% of the R-R interval), in 7 (11.7%) it was during the end-systolic phase (30-49% window), and in 6 (10%) it was during the mid-diastolic phase (70-89% window). In 53 of the 60 controls (88.3%) the optimal reconstruction phase was mid-diastole; it was end-systole in 4 (6.7%). There was a significant difference in the frequency of the optimal reconstruction phases between the AF patients and the controls but not in the visual scores for image quality and the number of assessable coronary segments. We observed no significant correlation between the mean HR and the visual image quality score. In AF patients there was a significant correlation between HR variability and the visual image quality scores.

The optimal reconstruction phase window in most patients with AF was end-diastole (90-99% of the R-R interval); the images had fewer motion artifacts and were of better diagnostic quality.

End-diastolic phase reconstruction shows fewer motion artifacts compared to the other cardiac phase reconstruction in three-fourths of patients with AF. 

Yuki, H, Oda, S, Honda, K, Yoshimura, A, Katahira, K, Yamashita, Y, Utsunomiya, D, Namimoto, T, Nakaura, T, Hirata, K, Kidoh, M, 256-Slice Coronary CT Angiography in Patients with Atrial Fibrillation: Optimal Reconstruction Phase and Image Quality.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14008213.html