Ultra-low radiation dose and contrast volume CT protocol and TAVI-CT score for TAVI planning and outcome

Abstract

Objective: To investigate the feasibility of an ultra-low radiation dose and contrast volume protocol using third-generation dual-source (DS) CT for transcatheter aortic valve implantation (TAVI) planning with coronary artery disease (CAD) assessment, coronary artery calcium score (CACS) and aortic valve calcium score (AVCS) quantification and to evaluate their relationship with TAVI outcome. Methods: In this retrospective study were selected 203 patients (131 males, 79.4 ± 5.4 years) underwent to TAVI and at 30- and 90-day follow-up. All patients had performed a third-generation 2 × 192-slices DSCT. The CT protocol included a non-contrast and a contrast high-pitch aortic acquisition for TAVI planning and CAD assessment. Semi-qualitative and quantitative image analysis were performed; the performance in CAD assessment was compared with ICA; the relationship between AVCS and CACS and paravalvular aortic regurgitation (PAR) and major cardiovascular events (MACEs) were evaluated. Mean radiation dose were calculated. Non-parametric tests were used. Results: Semi-qualitative image analysis was good. Contrast enhancement >500 Hounsfield unit (HU) and contrast-to-noise ratio <20 were obtained in all segments. The diagnostic accuracy in CAD was 89.0%. AVCS was significantly higher in patients with 30-day severe PAR. AVCS and CACS were higher in patients with 90-day MACE complications, respectively, 1904.5 ± 621.3 HU (p < 0.0001) and 769.2 ± 365.5 HU (p < 0.0230). Mean radiation dose was 2.8 ± 0.3 mSv. Conclusion: A TAVI planning ultra-low radiation dose and contrast volume protocol using third-generation DSCT provides highly diagnostic images with CAD assessment, AVCS and CACS quantification and these latter were related with TAVI outcomes. Advances in knowledge: The proposed protocol using third-generation 2 × 192-slices DSCT allows with an ultra-low radiation dose and contrast volume the TAVI planning and the coronary artery assessment.

Cardiac Magnetic Resonance and Cardiac Implantable Electronic Devices: Are They Truly Still “Enemies”?

“…The limitations of the use of these techniques are mainly due to their limited availability and the lack of adequate literature supporting their diagnostic accuracy, especially for the PC technique, although more studies are emerging in support of this method. Additionally, CT involves the use of ionizing radiation, although significant technological advances have greatly reduced radiation doses [72][73][74]. Finally, it must be considered that the presence of CIEDs may induce image artifacts, such as photon starvation/beam hardening, which can reduce the late iodine enhancement detection [65].…”