Multi-detector computed tomography is equivalent to trans-oesophageal echocardiography for the assessment of the aortic annulus before transcatheter aortic valve implantation.

Objectives: In transcatheter aortic valve implantation (TAVI), assessment of the aortic annulus is mandatory. We sought to investigate the correlation between trans-oesophageal echocardiography (TEE) and multi-detector computed tomography (MDCT) for annulus diameter assessment before TAVI.
Methods: A total of 122 patients (67 male, mean age 84 ± 6 years) underwent MDCT and TEE for TAVI planning. In TEE annulus diameters were obtained in a long-axis view at diastole. MDCT data were evaluated using MPR images, and corresponding projections were adjusted for MDCT and TEE. Patients were classified by the predominant localisation of aortic valve calcifications, and annulus diameters between TEE and MDCT were correlated. Additionally, the eccentricity of the aortic annulus was calculated.
Results: Mean eccentricity of the aortic annulus determined by MDCT was 0.34 ± 0.17, with no difference according to valve calcification. Regarding the aortic annulus diameter, the mean values measured were 24.3 ± 2.1 mm in MDCT and 24.0 ± 2.5 mm in TEE (P < 0.0001 for agreement).
Conclusions: Independent of the pattern of aortic valve calcification, close correlation is found between CT and TEE measurements of the aortic annulus diameter. In addition, CT demonstrates the non-circular shape of the aortic annulus.
Key Points: Accurate assessment of aortic annulus before transcatheter aortic valve implantation is crucial. Trans-oesophageal echocardiography has been the preferred method for aortic annulus assessment. We demonstrated a strong correlation between TEE and CT for annulus dimensions. CT reliably demonstrates the non-circular shape of the aortic annulus. CT could therefore be generally used for aortic annulus assessment before TAVI.