New protocol for contrast media reduction in atrial fibrillation ablation-planning CT with dual region of interest

• Published in: Radiography (London, England. 1995)
• Main Authors: Fan, R.H., Tomizawa, N., Sato, H., Fujimoto, S., Kawaguchi, Y.O., Nozaki, Y.O., Takahashi, D., Kudo, A., Inage, H., Yokota, T., Kudo, H., Kawamoto, K., Kogure, Y., Kumamaru, K.K., Minamino, T., Aoki, S.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 11.09.2024
• Subjects: Bolus tracking techniques; Cardiac computed tomography; Contrast media reduction; Dual region of interest; Protocol; Scan delay time; Af; Dual region of interest; LV; HU; AAo; BT; DAo; Contrast media reduction; S-ROI; Cardiac computed tomography; RIPV; Protocol; CKD; AKI; LIPV; RSPV; Bolus tracking techniques; ICC; PVs; ROI; LSPV; D-ROI; CT; PA; RFCA; LA; Scan delay time
• ISSN: 1078-8174; 1532-2831; 1532-2831
• DOI: 10.1016/j.radi.2024.08.016

Many patients with atrial fibrillation have impaired renal function, and therefore pre-operative CT for radiofrequency catheter ablation should minimize the use of contrast media. This study describes a dual-region-of-interest (D-ROI) protocol for the scanning of pulmonary veins and left atrium (PVs-LA) with less contrast media and optimized scan timing compared to the single-region-of-interest (S-ROI) protocol, without compromising image quality. This study retrospectively included 100 patients who underwent PVs-LA CT between July 2019 and February 2022. The participants were divided into two groups: Those scanned using the S-ROI method (Group A, n = 50), and those scanned using the D-ROI method (Group B, n = 50). Descriptive statistical analysis of the contrast effect and scan timing was performed using quantitative and qualitative data collected from both groups of images. The contrast media dose was larger in group A than in group B (63.6 ± 10.1 mL vs. 45.6 ± 6.9 mL; p < 0.001). The CT values of the PVs-LA did not differ significantly between groups A and B [434.2 ± 77.0 Hounsfield units (HU) and 428.8 ± 77.2 HU, respectively; p = 0.73]. Two evaluators determined appropriate scan timing (when PVs-LA reached a relatively sufficient contrast effect for diagnosis) in 23 (46%) and 45 (90%) patients from groups A and B, respectively (p < 0.001). Although the radiation dose is slightly increased compared with the S-ROI method, the D-ROI method provides improved scan timing and images with similar contrast enhancement while reducing the amount of contrast medium administered. The novel D-ROI bolus tracking technique can reduce the contrast medium dose while optimizing scan timing. [Display omitted]