Misidentification of the True Aortic Annulus with 2-dimensional Echocardiography: A Critical Appraisal Using 3-dimensional Imaging

Objectives This study aimed to evaluate the accuracy of identifying the 'true aortic valve (AV) annulus' using 2-dimensional (2D) echocardiography with the aim of highlighting potential misidentification issues in clinical practice. Design An observational study employing 3-dimensional (3D) datasets to generate 2D images of the AV annulus for analysis. Setting The study was conducted in an academic medical center. Participants Three-dimensional transesophageal echocardiography (3D TEE) datasets were obtained from 11 patients with normal AV and aortic root anatomies, undergoing coronary artery bypass surgery. Attending anaesthesiologists certified by the national board of echocardiography (NBE) were subsequently approached to participate in this study. Interventions Two images per patient were generated from 3D datasets, reflecting the mid-esophageal long-axis view of the AV: a 'True AV Annulus Image' and an 'Off-Axis Image'. A survey was distributed to NBE certified perioperative echocardiographers across 12 academic institutions to identify the 'true AV annulus' from these images. Measurements and Main Results The survey, completed by 45 qualified respondents, revealed a significant misidentification rate of the 'true AV annulus', with only 36.8% of responses correctly identifying it. The rate of correct identification varied across image sets, with 44.4% of participants unable to correctly identify any 'true AV annulus' image. Conclusions The study highlights the limitations of 2D echocardiography in accurately identifying the 'true AV annulus' in complex 3D structures like the aortic root. The findings suggest a need for greater reliance on advanced imaging modalities, such as 3D echocardiography, to improve accuracy in clinical practice.