Accuracy of three-dimensional echocardiography in candidates for transcatheter aortic valve replacement

The correct determination of aortic annulus dimensions is a crucial step to avoid complications in Transcatheter Aortic Valve Replacement (TAVR). Currently, the gold standard method for the evaluation of the aortic annulus is Multidetector Computed Tomography (MDCT), which is limited by the risk of contrast-induced nephropathy. Three-dimensional transesophageal echocardiography automated software (3DTEEa) have been used as an alternative in patients with contra-indications to MDCT. We aimed to evaluate the accuracy of 3DTEEa-derived aortic annulus dimensions; to assess the influence of calcification in the agreement between 3DTEEa and MDCT; and to determine reclassification in prosthesis size choice if 3DTEEa was the only imaging method. One hundred and seven consecutive patients referred for TAVR were studied. Aortic annulus dimensions were determined using MDCT and 3DTEE manual (3DTEEm) and automated measurements. Valve calcification was assessed with MDCT. Limits of agreement (LOA) were narrower for 3DTEEa (minimum diameter: mean bias 0.60; LOA - 2.94 to 4.14; maximum diameter: mean bias 0.20; LOA - 3.82 to 4.22) as compared to 3DTEEm (minimum diameter: mean bias 0.22; LOA - 3.84 to 4.28; maximum diameter: mean bias - 1.25; LOA - 6.37; 3.86). Compared to MDCT, 3DTEEa overestimated while 3DTEEm underestimated most parameters. No differences were found in average bias between methods according to quartiles of valve calcification. Most patients would have received the same size valve (63.9%) if 3DTEEa was the only available method. Measurement of aortic annulus dimensions using a 3DTEE automatic software is feasible and not influenced by valve calcification. It may be an alternative for patients who cannot undergo MDCT.