Abstract
BACKGROUND: A high heart rate (HR) increases motion artifacts in coronary computed tomography angiography (CCTA). This retrospective study aimed to investigate the feasibility of using a novel electrocardiogram (ECG)-edit technique involving alternate trigger deletion to improve the quality of 64-slice CCTA images in patients with increased HR. METHODS: This retrospective single-center study enrolled 53 symptomatic cardiac patients with increased HR (≥75 beats per minute). CCTA was acquired on a 64-slice computed tomography (CT) scanner using a retrospective ECG-gated acquisition protocol. Images were reconstructed without the ECG-edit function, and with the ECG-edit function of alternate trigger deletion. Two experienced radiologists evaluated the subjective image quality of the coronary artery segments using a four-point Likert scale (on which 1 represented non-interpretable, and 4 represented excellent). The interpretability and objective image quality of the two reconstruction methods were compared. RESULTS: In total, 53 patients (mean age: 57.57±14.78 years; 29 men) were included in the study. The implementation of the ECG-edit significantly improved the Likert scores and interpretability at the per-segment (2.94±0.70 vs. 1.97±0.78; 96.23% vs. 70.00%), per-artery (3.18±0.53 vs. 1.93±0.61; 89.81% vs. 47.80%), and per-patient (3.87±0.34 vs. 2.89±0.64; 69.81% vs. 13.21%) levels (all P<0.001). In terms of the objective image quality assessment, the ECG-edit function significantly improved the mean contrast density (290.37±82.34 vs. 215.82±88.37) and the signal-to-noise ratio (6.99±3.96 vs. 5.41±3.27) compared to the non-ECG-edit approach (both, P<0.001). CONCLUSIONS: The ECG-edit function of alternate trigger deletion for CCTA improved the subjective image quality, interpretability, and objective image quality of patients with increased HR.