Value of the Non-enhanced Cardiac Computed Tomography Scan Analysis in Determination of the Appropriate Coronary CT Angiography Scan Protocol.

Abstract

Objective: Coronary computed tomography angiography (CCTA) is a cornerstone in the assessment of coronary artery disease. Despite technological advancements, balancing radiation does with diagnostic image quality remains a challenge. This study evaluates whether assessing preliminary non-enhanced CT scans allows for the optimization of CCTA gating protocols to enhance image quality and minimize radiation exposure.

Methods: We prospectively analyzed 150 patients undergoing CCTA on a 256-slice scanner. Non-enhanced scans were used to identify motion artifacts or anatomical challenges. Based on these findings, a specific gating protocol (prospective, prospective with padding, or retrospective) was selected. This cohort was compared to a control group of 150 standard CCTAs performed without protocol pre-selection. Image quality was assessed on a four-point scale, and radiation doses were recorded.

Results: The mean patient age was 49 years, with a mean heart rate (HR) of 62 ± 14 beats per minute (bpm). Subjective image quality was significantly higher in the pre-selection group, particularly for patients with HR > 65 bpm (3.5 ± 0.5 vs. 2.8 ± 0.8; p = 0.06). The mean radiation dose was significantly lower in the pre-selection group (4.9 ± 1.4 vs. 7.5 ± 1.8 mSv; p < 0.01). Furthermore, the requirement for high-radiation protocols (padding or retrospective gating) was reduced by 50% in the pre-selection group (14/150 vs. 28/150 scans).

Conclusion: Utilizing non-enhanced CT scans to tailor 256-slice CCTA protocols significantly improves image quality and reduces radiation exposure. This strategy offers a more personalized approach to cardiac imaging and should be considered for routine clinical practice.