Impact of three‐dimensional transesophageal echocardiography on prosthesis sizing for transcatheter aortic valve implantation

OBJECTIVES: To compare aortic annulus diameters obtained by 3D transesophageal echocardiography (TEE) with 2D-TEE and the impact on prosthesis size selection in transcatheter aortic valve implantation (TAVI). BACKGROUND: In TAVI the aortic annulus diameter determines prosthesis size. The ideal modality for annulus assessment has not been defined yet. METHODS: Annulus diameters in 2D-TEE (long-axis view) and in 3D-TEE (long-axis view in multiple-plane-reconstruction) were compared in consecutive patients with aortic stenosis screened for TAVI. Prosthesis size was selected according to industry guidelines, integrating data from 3D-TEE, angiography and computed tomography. The percentage of cases in which 2D-TEE and 3D-TEE correctly predicted final prosthesis size was calculated. RESULTS: Forty-nine patients were studied (Age 80 ± 5, 39% male, logistic EuroScore 17 ± 11%). Annulus diameters from 2D- and 3D-TEE correlated (r = 0.808, P < 0.0001). Mean diameters were significantly larger on 3D- vs. 2D-TEE (23.4 ± 2.2 vs. 22.1 ± 2.6 mm, P < 0.001) with a mean difference of 1.2 mm (limits of agreement: -1.8 to 4.3). The interobserver variability of 2D- and 3D-TEE was 3.5 ± 5.6% and 0.9 ± 5.1%, respectively. Thirty-nine patients underwent TAVI (27 CoreValve™, 12 Edwards Sapien™). The procedure was successful in 37 (95%) patients. Postprocedural regurgitation was none or mild in 89% of the cases with no severe insufficiency. Final prosthesis size was correctly predicted by 2D-TEE in 67% while in 80% by 3D-TEE. Overall, 3D-TEE suggested a different prosthesis size in 26% of all cases compared to 2D-TEE. CONCLUSIONS: Aortic annulus measurement by 3D-TEE yields significantly larger diameters than 2D-TEE. This impacts prosthesis size selection in a considerable percentage of cases.