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Objective: To investigate the impact of motion correction (MC) algorithm on image quality of coronary artery in cardiac phantom undergoing coronary CT angiography (CCTA), with assessment of the influence of heart rate, contrast agent concentration and AsiR-V ratio. Methods: A cardiac beating phantom underwent CCTA with 16cm-detector CT scanner. The mimic coronary arteries were filled with 3 different concentration contrast agent (650HU, 450HU, 250HU) and tube voltage (80, 100, 120kV). The heart rate was set from 60-130bpm. The scan was ECG-gated and prospectively triggered. All images acquired with 80bpm, 120kV, 375mA were reconstructed using different AsiR-V ratio (0%, 30%, 50%, 70%). The signal to noise ratio (SNR) and noise of images reconstructed with different AsiR-V ratios were compared. The RCA with small diameter (1mm) and LCA with large diameter (4mm) on the phantom were analyzed. The image quality of coronary artery was defined according to the four-score classification system. The influence of heart rate, contrast agent concentration and AsiR-V ratio on MC to image quality was assessed by tendency chart. Results: For RCA, the MC helps to image quality improvement irrespective of the heart rate and contrast agent concentration. While, the image quality of LCA only improves in the case of 60-70bpm HR and 650HU contrast agent concentration. The SNR and noise have a positive and negative relationship with AsiR-V ratio respectively, irrespective of contrast agent concentration. The AsiR-V has contributed to the improvement of image quality by MC in the case of higher heart rate (80-90bpm) and lower contrast agent concentration for both RCA and LCA, but no statistical significance among groups with different AsiR-V ratio. Higher tube voltage has no contribution to the improvement of coronary artery image quality among three different contrast agent concentration groups. Conclusion: For mimic RCA with relative small diameter (about 1mm), high contrast agent concentration (650HU) and AsiR-V will aid MC to acquire better image quality of coronary artery, especially in those with higher heart rate (90-130bpm). Consequently, adequate contrast agent volume and injection speed and AsiR-V will help MC take effect on image quality improvement, especially in small vessel at higher heart rate.