Effect of a breathing exercise program on coronary artery motion artifacts in 256 rows of coronary computed tomography angiography in patients with different heart rate variability.

BACKGROUND

Coronary artery motion artifact is a major limitation of coronary computed tomography angiography (CCTA). The purpose of this study was to investigate the effect of respiratory status on coronary motion artifacts under different heart rate variability (HRV) conditions.

METHODS

Between January 2022 and January 2024, 935 CCTA patients were prospectively enrolled and randomly assigned to a breath-holding group (group A) and a free-breathing group (group B), and each group was subdivided into three subgroups based on HRV ≤3 bpm, HRV 4-10 bpm, and HRV ≥11 bpm. Subjective image quality was assessed using a four-point Likert scale: 4 points = excellent, no artifacts; 1 point = severe artifacts, unassessable. Between-group comparisons were made to contrast and analyze the subjective image quality of the three subgroups in the free-breathing protocol and the breath-holding protocol. Within-group comparisons were compared and contrasted to analyze the relationship between subjective image quality and HRV.

RESULTS

In the between-group comparisons, with the breath-holding protocol as a comparison, HRV ≤3 bpm (3.95±0.32 3.95±0.31), HRV 4-10 bpm (3.94±0.32 3.93±0.37), and HRV ≥11 bpm (3.92±0.37 3.92±0.38) free-breathing in the three subgroups did not show statistically significant differences on coronary artery motion artifacts (all P>0.05). For within-group comparisons, subjective image quality was independent of HRV.

CONCLUSIONS

The combination of a 140-ms time resolution, a 16-cm wide detector, and the second-generation reconstruction algorithm can be used jointly to realize free-breathing CCTA under different HRV conditions, which broadens the application range of CCTA.