Low contrast medium-volume third-generation dual-source computed tomography angiography for transcatheter aortic valve replacement planning
To investigate feasibility, image quality and safety of low-tube-voltage, low-contrast-volume comprehensive cardiac and aortoiliac CT angiography (CTA) for planning transcatheter aortic valve replacement (TAVR).
Materials and methods
Forty consecutive TAVR candidates prospectively underwent combined CTA of the aortic root and vascular access route (270 mgI/ml iodixanol). Patients were assigned to group A (second-generation dual-source CT [DSCT], 100 kV, 60 ml contrast, 4.0 ml/s flow rate) or group B (third-generation DSCT, 70 kV, 40 ml contrast, 2.5 ml/s flow rate). Vascular attenuation, noise, signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were compared. Subjective image quality was assessed by two observers. Estimated glomerular filtration (eGFR) at CTA and follow-up were measured.
Besides a higher body-mass-index in group B (24.8±3.8 kg/m2 vs. 28.1±5.4 kg/m2, P=0.0339), patient characteristics between groups were similar (P≥0.0922). Aortoiliac SNR (P=0.0003) was higher in group B. Cardiac SNR (P=0.0003) and CNR (P=0.0181) were higher in group A. Subjective image quality was similar (P≥0.213) except for aortoiliac image noise (4.42 vs. 4.12, P=0.0374). TAVR-planning measurements were successfully obtained in all patients. There were no significant changes in eGFR among and between groups during follow-up (P≥0.302).
TAVR candidates can be safely and effectively evaluated by a comprehensive CTA protocol with low contrast volume using low-tube-voltage acquisition.
• Third-generation dual-source CT facilitates low-tube-voltage acquisition.
• TAVR planning can be performed with reduced contrast volume and radiation dose.
• TAVR-planning CT did not result in changes in creatinine levels at follow-up.
• TAVR candidates can be safely evaluated by comprehensive low-tube-voltage CT angiography.
KeywordsAortic stenosis Aortoiliac CT angiography Contrast medium Dual-source CT Transcatheter aortic valve replacement
The scientific guarantor of this publication is U. Joseph Schoepf. The authors of this manuscript declare relationships with the following companies: UJS is a consultant for and/or receives research support from Bayer, Bracco, GE Healthcare, Medrad and Siemens. The other authors have no conflicts of interest to disclose. This study was funded by a research grant from GE Healthcare (award number 12-VIS-003), who also provided contrast medium for this study. No complex statistical methods were necessary for this paper. Institutional Review Board approval was obtained. Written informed consent was obtained from all subjects (patients) in this study. No study subjects or cohorts have been previously reported. Methodology: prospective, diagnostic or prognostic study, performed at one institution.
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