Four-dimensional Computed Tomography Study of the Tricuspid Annulus Deformation During the Cardiac Cycle
The tricuspid valve undergoes a series of geometrical deformations throughout the cardiac cycle. Right ventricular function and left ventricular diseases were associated with the tricuspid valve behavior. The purpose of this study was to determinate if the tricuspid annulus (TA) deformation could be assessed by multiphase computed tomography (CT) imaging. With this technique, 3D volumes can be acquired in »10 instants of the cardiac cycle with high spatial resolution. Besides collecting several morphological features of the TA, we looked for the best-fit plane to the dataset using a principal component analysis to evaluate the TA planarity. Algorithms were tested using images from a 67 years old patient. TA area was estimated in 3D and in 2D projecting the points into the fitted plane. In our patient, mean TA areas were 17.7 ± 0.9 and 16.4 ± 0.9 cm2, respectively. Average root mean square errors of the fitting plane were 2.8 ± 0.3 mm. The was no correlation between TA area and planarity. The use of a 4D multiphase CT technique, which adds the time dimension to the standard 3D together with image processing algorithms, was a reliable method to assess geometrical deformation of the TA.