Cardiac Structural and Functional Evaluation Using a Heart Motion Correction Algorithm for Coronary Computed...

The heart motion correction algorithm used in current multi-slice computed tomography (CT) is sufficient for coronary artery imaging in patients with high heart rates. However, the effect of this algorithm on the image quality in whole-cardiac-cycle reconstructions remains unclear. Therefore, this study aimed to investigate image quality, segmentation performance, and cardiac structure and function assessment using a heart motion correction algorithm for coronary CT angiography in patients with rapid heart rates.

This study retrospectively collected data from 58 consecutive patients with high heart rates (≥80 beats/min), of whom 36 also underwent cardiac magnetic resonance (CMR) imaging. CT images were reconstructed from 0% to 100% in 5% increments using the standard reconstruction (STD) and second-generation snapshot freeze (SSF2) protocols, and then processed by an automatic heart segmentation algorithm. Image quality, segmentation performance, cardiac volumes, and functional parameters were compared between protocols.

Compared with the STD protocol, the SSF2 protocol yielded a higher image quality score (3.91 ± 0.29 vs. 3.84 ± 0.37; p < 0.01), a steeper edge rise slope (41.71 ± 19.03 vs. 25.59 ± 13.16; p < 0.01), and lower entropy (4.12 ± 0.48 vs. 4.40 ± 0.28; p < 0.01). For left ventricular end-diastolic volume, the intraclass correlation coefficient (ICC) between automatic segmentation and manual contouring for the SSF2 protocol was 0.96, and the coefficient of variation was 7.84%. In contrast, the coefficients of variation for left ventricular end-systolic volume were poor (48.24% for STD and 48.18% for SSF2). Differences in global circumferential strain (-13.30 ± 3.42 vs. -15.01 ± 4.44; p < 0.01) and global longitudinal strain (-11.80 ± 4.83 vs. -13.01 ± 4.36; p < 0.01) between SSF2 and CMR were statistically significant, although correlations (ICC = 0.90 and 0.85, respectively) were good.

SSF2 significantly improves image quality, structure, and function, and enables strain assessment in whole-cardiac-cycle reconstructions in patients with high heart rates. SSF2 also demonstrates superior performance over the STD protocol for evaluating myocardial strain.