Prospectively Electrocardiogram-Gated High-Pitch Spiral Acquisition Mode Dual-Source CT Coronary Angiography in Patients with High Heart Rates: Comparison with Retrospective Electrocardiogram-Gated Spiral Acquisition Mode

Abstract

ObjectiveTo assess the image quality and effective radiation dose of prospectively electrocardiogram (ECG)-gated high-pitch spiral acquisition mode (flash mode) of dual-source CT (DSCT) coronary angiography (CTCA) in patients with high heart rates (HRs) as compared with retrospectively ECG-gated spiral acquisition mode.Materials and MethodsTwo hundred and sixty-eight consecutive patients (132 female, mean age: 55 ± 11 years) with mean HR > 65 beats per minute (bpm) were prospectively included in this study. The patients were divided into two groups. Collection was performed in group A CTCA using flash mode setting at 20-30% of the R-R interval, and retrospectively ECG-gated spiral acquisition mode in group B. The image noise, contrast-to-noise ratio (CNR), image quality scores, effective radiation dose and influencing factors on image quality between the two groups were assessed.ResultsThere were no significant differences in image quality scores and proportions of non-diagnostic coronary artery segments between two groups (image quality scores: 1.064 ± 0.306 [group A] vs. 1.084 ± 0.327 [group B], p = 0.063; proportion of non-diagnostic coronary artery segments: segment-based analysis 1.52% (group A) vs. 1.74% (group B), p = 0.345; patient-based analysis 7.5% (group A) vs. 6.7% (group B), p = 0.812). The estimated radiation dose was 1.0 ± 0.16 mSv in group A and 7.1 ± 1.05 mSv in group B (p = 0.001).ConclusionIn conclusion, in patients with HRs > 65 bpm without cardiac arrhythmia, the prospectively high-pitch spiral-acquisition mode with image-acquired timing set at 20-30% of the R-R interval provides a similar image quality and low rate of non-diagnostic coronary segments to the retrospectively ECG-gated low-pitch spiral acquisition mode, with significant reduction of radiation exposure.

The Impact of Different Levels of Adaptive Iterative Dose Reduction 3D on Image Quality of 320-Row Coronary CT Angiography: A Clinical Trial

“…The reduction of radiation dose is associated with an increase of noise and, as a result, a deterioration of image quality [ 3 ]. Currently, the radiation exposure of a CTA performed with 320-row CT ranges between 2–5 mSv [ 1 , 4 ] and routinely, filtered back projection (FBP) is used to reconstruct the dataset. To improve the trade-off between image quality and radiation dose, noise reduction filters such as quantum denoising software (QDS) can be applied in conjunction with FBP reconstruction [ 5 ].…”

ECG-triggered high-pitch CT for simultaneous assessment of the aorta and coronary arteries

“…Because relevant clinical information can be obtained for the ascending aorta and coronary arteries, we recommend this protocol for aortic disease. The use of a systolic window for high heart rate has been proposed by Sun et al 21 and Goetti et al 22 to improve the image quality of coronary arteries. Systolic imaging was not used in patients with fast heart rate as it induces a significant change in aortic diameter by comparison to diastolic imaging and as our referring physician were used to diastolic imaging.…”

Coronary Computed Tomography Angiography

“…Both options are optimal if either a scanner with 256 or more slices or a DSCT is used. Furthermore, use of DSCT enables further decrease due to its higher pitch rates at higher heart rates, since multisegment reconstruction is not necessary [33,34]. Additional reduction is accomplished by a tube voltage of 100 kV or even 80 kV instead of the usual 120 kV, which can be performed depending on the patient's body mass [30,31].…”