ECG-gated multidetector CT angiography plays a key role for planning of transcatheter aortic valve implantation (TAVI), allowing to perform accurate measurements of the aortic annulus for proper prosthesis sizing by tracking its dynamical changes duringthe systolic and diastolic phases of the cardiac cycle. To this purpose, acquiring ECG-gated images of the aortic root with maximum aortic valve opening seems attractive in order to avoid underestimating prosthesis size, thuspotentially minimizing the risk of paraprosthetic regurgitation. Our aim is to assess the dynamical changes of aortic annulus...

Fourteen nonobese patients (age 76 ÷ 91 years, male:female ratio 10:4) with severe aortic valve stenosis candidate to TAVI, and ten nonobese patients (age 57 ÷ 75 years, male:female ratio 6:4) with suspected CAD underwent a CT coronary angiography examination with retrospective ECG-gating on a high definition 64-row CT scanner (Discovery CT750 HD™, GE Healthcare, Milwaukee, WI, USA). All CT angiography examinations were carried out with the following parameters: detector configuration 64×0.625mm, slice thickness 0.625mm, tube voltage 100-120kV, tube current 400-600mA, tube rotation time 0.35...

Biometric parameters of the aortic annulus of patients from the TAVI and control groups are reported in Table 1 and Table 2 , respectively. In the TAVI group astatistically significant difference was detected for all parameters except the perimeter (p=0.2099), whereas in the control group the only parameter without a statistically significant difference was the maximum diameter (p=0.0762). The temporal variations of biometricparameters over the cardiac cycle are shown by diagrams in Fig. 2andFig. 3andinTable 3 . In particular, size differences between the 0-20% and...

All annular size parameters tend to decrease going from telesystole to telediastole. The ellipticity index tends to decrease going towards the systolic phase, showing that the aortic annulus has a more circular shape in systole. Perimeter is the most consistent parameter. We believe that an accurate multiparametric measurement of the aortic annulus size may provide valuable information for the most appropriate prosthesis choice in patients candidate to TAVI, potentially minimizing the risk of paraprosthetic regurgitation.

Achenbach S, Delgado V, Hausleiter J, Schoenhagen P, Min J, Leipsic J. SCCT expert consensus document on computed tomography imaging before transcatheter aortic valve implantation (TAVI)/transcatheter aortic valve replacement (TAVR). J Cardiovasc Comput Tomogr 2012; 6:366-380 Bertaso AG, Wong DT, Liew GY et al. Aortic annulus dimension assessment by computed tomography for transcatheter aortic valve implantation: differences between systole and diastole. Int J Cardiovasc Imaging 2012; 28:2091-2098 Blanke P, Russe M, Leipsic J et al. Conformational pulsatile changes of the aortic annulus: impact on prosthesis...