Transoesophageal echocardiography of aortic atherosclerosis: The additive value of three-dimensional over two-dimensional imaging

Abstract

Aims Complex aortic atherosclerotic plaques (AAPs) carry a significant risk of embolism. Currently, two-dimensional (2D) transoesophageal echocardiography (TOE) is the principal diagnostic tool of AAPs. However, we hypothesized that the data obtained from three-dimensional (3D) imaging may improve AAPs' spatial assessment. Methods and results The study included 67 patients (aged 70±15 years, 35 men), who had routine TEE studies. The thoracic aorta was studied from arch to distal descending aorta, using the x-plane mode (simultaneous short- and long-axis views). If focal intimal thickening (suggestive of AAP) was detected, the 3D zoom algorithm was exercised on the specific site with further post-processing on a Q-lab workstation to measure its thickness in the X, Y, and Z dimensions. The AAP contour was defined qualitatively as regular or irregular in each mode. A total of 100 AAPs were investigated. The AAP thickness estimation was significantly greater in the 3D mode than in the 2D mode (0.51±0.33 vs. 0.28±0.20 cm, P < 0.001). The rate of complex AAPs (defined by AAP thickness of ≥4 mm) was two-fold higher with 3D imaging than with 2D imaging (27% with 2D imaging alone vs. 53% with the addition of 3D imaging). The rate of irregular AAPs increased from 29 to 65% when assessed with 3D imaging compared with 2D imaging. Conclusion This study has shown a significant difference in the estimation of AAPs between 2D and 3D TEE. The significant shift to a more complex AAPs profile may suggest that 3D imaging is preferable for the assessment of aortic atherosclerosis burden.