Improved image quality of coronary CT angiography using automatic motion correction

Background: Motion artifacts that degrade image quality of coronary CT angiography (CCTA) in patients with high heart rates may be reduced with specific automatic motion correction algorithms (AMC). Objectives: We compared coronary-artery delineation between AMC and conventional CCTA reconstruction (CR). Patients and Methods: CCTA images (clinical single-source-64-slice-CT system) of 17 consecutive patients with heart rates exceeding 55 bpm were reconstructed with both CR and AMC during the individually best-suited phase of the cardiac cycle. Two independent readers who were blinded to the reconstruction algorithm scored image quality of each coronary artery segment (AHA 15-segment-model; 1: non-diagnostic - 4: excellent). In case of disagreement a third blinded reader assigned a final score. Two-tailed statistical tests (Wilcoxon-matched-pairs, Pearson-correlation) were significant at P < 0.05. Results: Mean heart rate during CCTA was 61 ± 8 bpm. CCTA quality improved significantly in the RCA (good-or-excellent in 11/17 AMC vs. 5/17 CR, P = 0.018) and LAD (15/17 vs. 7/17, P = 0.031). Non-diagnostic CCTA in the RCA, LM, LAD, and LCX reduced from 16/68 (CR, 24%) to 7/68 (AMC, 10%). Significant motion correction was observed at low (≤ 60 bpm; P = 0.008), intermediate (61-70 bpm; P < 0.001), and high heart rates (> 70 bpm; P = 0.021). Inter-reader agreement was good. (inter-class-correlation, 0.762). Conclusions: CCTA image quality improves significantly with AMC in patients with high heart rates and reduces the proportion of non-diagnostic examinations.