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Published on: June 3, 2018
Absolute-Delay Multiphase Reconstruction Reduces Prosthetic Valve-Related and Atrial Fibrillation-Related Artifacts
Young Joo Suh1, Dong Jin Im1, Yoo Jin Hong1
11 All authors: Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea.
Insights
Absolute-delay multiphase reconstruction significantly improves cardiac CT image quality for mechanical valves in patients with irregular heart rates compared to relative-delay reconstruction.
Area of Science:
- Medical Imaging
- Cardiovascular Imaging
- Computed Tomography
Background:
- Assessing mechanical valves with cardiac CT is challenging in patients with irregular heart rates.
- Irregular heart rhythms can degrade image quality, impacting diagnostic accuracy.
Purpose of the Study:
- To compare the effectiveness of absolute-delay multiphase reconstruction versus relative-delay multiphase reconstruction for cardiac CT imaging of mechanical valves.
- To evaluate the impact of these reconstruction techniques on image quality in patients with irregular heart rates.
Main Methods:
- A study included 26 patients with 40 mechanical valves and atrial fibrillation during CT.
- Image quality was assessed on a 4-point scale for valvular and subvalvular regions.
- Statistical analysis using paired t test or Wilcoxon signed rank test compared reconstruction techniques.
Main Results:
- Absolute-delay reconstruction yielded significantly higher image quality scores (p < 0.0001) for both valvular (3.55 ± 0.60) and subvalvular (3.35 ± 0.66) regions compared to relative-delay (2.93 ± 0.73 and 2.80 ± 0.79, respectively).
- Nondiagnostic images in three valves (7.5%) with relative-delay reconstruction were improved to diagnostic quality with absolute-delay reconstruction (p < 0.0001).
Conclusions:
- Absolute-delay multiphase reconstruction offers superior image quality for cardiac CT of mechanical valves in patients with irregular heart rates.
- This technique enhances diagnostic confidence and reduces nondiagnostic studies in challenging patient populations.
Objective:
The objective of our study was to compare the image quality of cardiac CT images of mechanical valves in patients with irregular heart rates (HRs) using absolute-delay multiphase reconstruction versus relative-delay multiphase reconstruction.
Materials And Methods:
A total of 26 patients with 40 mechanical valves who had atrial fibrillation during CT were included. The image quality of the CT scans was assessed for the subvalvular and valvular regions on a 4-point scale. The paired t test or Wilcoxon signed rank test was used to compare image quality scores between the relative-delay and absolute-delay reconstruction techniques. The overall image quality score was determined as the mean of the valvular and subvalvular region scores.
Results:
For valvular regions, the image quality scores were 2.93 ± 0.73 (mean ± SD) for the relative-delay reconstruction technique and 3.55 ± 0.60 for the absolute-delay reconstruction technique (p < 0.0001). For subvalvular regions, the image quality scores were 2.8 ± 2.80 ± 0.79 and 3.35 ± 0.66 for the relative- and absolute-delay reconstructions (p < 0.0001), respectively. The nondiagnostic image quality group consisted of relative-delay reconstruction images of three valves (7.5%); the image quality scores for the absolute-delay reconstruction images of all three valves were improved, and the absolute-delay reconstruction images of the three valves were of diagnostic quality (p < 0.0001).
Conclusion:
Absolute-delay multiphase reconstruction can improve CT image quality of mechanical valves in patients with an irregular HR compared with relative-delay reconstruction.
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