Tricuspid Annulus Measurements in Severe Tricuspid Regurgitation: Comparative Analysis of Cardiac-Gated Computed Tomography Versus Three-Dimensional Transesophageal Echocardiography.

Background: Treatment options for severe tricuspid regurgitation (TR) require a multimodal analysis of the tricuspid annulus (TA). Cardiac computed tomography (CT) is currently considered the gold standard for annular perimeter measurements, though three-dimensional transesophageal echocardiography (3D TEE) can yield similar results. As such, we sought to determine the accuracy and precision of 3D TEE imaging of the TA perimeter compared to CT imaging in outpatients with severe TR. Methods: Fifty-five patients were referred for multimodality workup for severe TR that included CT and 3D TEE. The 3D TEE imaging was performed in the mid-esophageal (ME) and transgastric views. A semiautomated software program was used to identify and measure the TA with additional manual optimization by the reader. These 3D TEE measurements were compared to cardiac CT imaging. Results: Out of 55 patients, 3 were excluded for hiatal hernias and 1 was excluded for severe kidney disease. Fifty-one studied patients had an average age of 76 ± 10 years with 59% female. The 3D TEE analysis of the TA perimeter demonstrated an excellent correlation with CT from the ME view, R = 0.88, and from the TG view, R = 0.86, with an average difference of approximately 8.5% when compared to CT. TEE inter-reader variability was approximately 6%, whereas CT variability was 1.4. Conclusions: The 3D TEE TA perimeter measurements are accurate when compared to CT with a variability of 8.5%. While CT remains more precise, 3D TEE imaging for TA sizing should be considered a near-equivalent modality to CT.