Application of a Series of Two-Dimensional Transesophageal Echocardiographic (2D TEE) Views Across Multiple Axes Improves the Accuracy of Tricuspid Annular Measurements

Objectives: Quantification of the tricuspid annulus (TA) is an important factor in determining the requirement for tricuspid annuloplasty in cardiac surgery. Three-dimensional echocardiography (3DE) has shown that the TA is biplanar with an antero-posterior longaxis and septo-lateral shortaxis, and that the commonly used 2D TEE (two-dimensional transesophageal echocardiography) four-chamber view (4ChV) underestimates the true TA longaxis. The authors hypothesized that the use of multiple 2D TEE TA views could attain greater TA long-axis measurements and smaller TA short-axis measurements than the 4ChV, and that the 4ChV has a significant but inconsistent bias relative to the maximal TA diameter measured by these views. Design: Prospective observational study. Setting: Adult tertiary teaching hospital. Participants: 45 adult patients. Interventions: Multiplanar 2D TEE assessment of the tricuspid annulus. Measurements and main results: Multiplanar assessment reliably produced larger TA long-axis measurements (93% of patients, 95% confidence interval: 81-98%) of (mean [95% confidence interval]) 40 mm (28-50 mm) compared with the 4ChV (34mm [25-44 mm], p < 0.0001) and smaller TA short-axis measurements (29 mm [20-38 mm], p < 0.0001) compared with the 4ChV. TA diameter by 4ChV assessment yielded an average bias of -5.6 mm, with 95% limits of agreement -15 to +3.9 mm compared with the largest TA long-axis measurement by multiplanar assessment. Conclusions: Multiplanar 2D TEE assessment of the TA long- and short-axis consistently achieves larger and smaller measurements, respectively, than the 4ChV. The 4ChV also is not a reliable index of the TA longaxis. If the time, proficiency, or equipment required for 3DE TA assessment are unavailable, the use of multiple standard and non-standard 2D TEE TA views may offer an alternative for TA assessment. (C) 2021 Elsevier Inc. All rights reserved.