The transgastric views are among the most important transesophageal views and are the best TEE views for evaluating left and right ventricular function. As such, transgastric views are commonly employed in operative TEE to assess ejection fraction and wall motion post-operatively. In addition, deep transgastric views are the best views in which one can obtain accurate gradients across the aortic valve to assess the degree of aortic stenosis or regurgitation.
Trangastric Short Axis
The transgastric short axis views are obtained by advancing the probe into the stomach and gently antiflexing. These views are similar to an inverted parasternal short axis view with the anterior wall on the bottom of the screen and the inferior wall at the top. By advancing and withdrawing the probe, short axis slices can be obtained at mitral valve level, papillary muscle level and at the LV apex. In addition, short axis views of the right ventricle, tricuspid valve and RVOT can be obtained via clockwise rotation of the probe.
Short Axis - Mitral Valve Level - 0 degrees
This is the only view on TTE with 2D imaging where all scallops of the mitral valve can be seen at once. It is a good view to look at issues with coaptation, and origins of MR. This view is obtained by slow withdrawing and antiflexing from the mid ventricular position. On occasional the omniplane angle needs to be increased up to 10 or 20 degrees
Short Axis - Mid Ventricle - 0 degrees
Similar to he parasternal on TTE but papillary muscles are seen at the midventricular level. Because we are in the stomach the posteromedial papillary muscle is the one closer to the probe. To obtain this view you need to be inserted more than the mitral valve level
Short Axis - Apex - 0 degrees
Inserting slight more (but not enough to get to deep transgastric views) you will get the short axis closer to the apex. The RV insertion points along all these short axis images defines the location of the septum. These three short axis views helps one assess LV function and for pericardial effusions around the LV.
Tricuspid Valve Short Axis 0 to 45 degrees
The tricuspid valve can be seen on short axis (similar to the mitral valve above) but clockwise rotation from at or insertion just below the level at which you obtained the mitral valve image above. Often one will need omniplane up to 45 degrees. This is the only TEE view where in 2D you can see all of the leaflets of the tricuspid valve simultaneously.
RVOT Views 30-60 degrees
Omniplane scanning further to 30-60 degrees and advancing the probe, the muscular right ventricular outflow tract and pulmonic valve can be visualized. This is one TEE view in which Doppler across the pulmonic valve is feasible to assess degree of PS or PR.