A Tool for Functional Anatomy Assessment of Aortic-Mitral Valve Coupling Studied Using New 3D Matrix Transesophageal Echocardiographic Probe

The mitral and aortic valves are coupled via fibrous tissue connecting the two annuli. An in-depth understanding of normal mitral-aortic valvular coupling and the ability to accurately assess changes in different disease states may be important, particularly in the context of valvular surgical planning and post-surgical assessment. However, this coupling is difficult to evaluate using two-dimensional imaging techniques because of the three-dimensional (3D) anatomy of these structures. Because the motion of the aortic valve complex is even more difficult to characterize, few studies have addressed in detail the functional anatomy of this valve in 3D. These studies have been mostly limited to invasive techniques based on implantation of crystals or radio-opaque markers in animals. Based on these findings, there is growing evidence that the dynamics of these two annuli throughout the cardiac cycle are inter-related, and that mitral-aortic valvular coupling is an integral part of the normal cardiac physiology. To allow the non-invasive evaluation of this coupling, it is essential to have a 3D technique that allows simultaneous imaging of both valves at sufficiently high spatial and temporal resolutions. The recently developed real-time 3D echocardiographic matrix array transesophageal (mTEE) transducer provides 3D images of higher spatial and temporal resolution than the earlier transthoracic images (figure 1). Our hypothesis was that these images could be suitable for: (1) detailed study of functional anatomy of the aortic valve, and (2) simultaneous analysis of mitral and aortic valves that would allow quantitative assessment of their dynamic behavior and accurate characterization of their coupling. To test this hypothesis, we developed new software tool for quantitative analysis of mitral and aortic valve dynamics from mTEE images.