From Echocardiography in ICU
This picture shows you the location of the main echocardiographic windows:
1- Parasternal window
2- Apical window
3- Subcostal (also called subxyphoid) window
This view is very useful to estimate the size and contractility of the right and left ventricle (septum and posterior wall), to assess the morphology and function of the mitral and aortic valves. With color Doppler you can look for an aortic or mitral regurgitation and try to determine their mechanism.
There are 3 levels of imaging the heart in short axis:
Base of the heart, level of the aortic valve
Mid-ventricle: papillary muscles and toward the apex
In this view you will be able to visualize the 4 main chambers of the heart: left ventricle and atrium, right ventricle and atrium. The Apical 4 chamber view is the best view to calculate the Simpson ejection fraction, to visualize the apex of the left ventricle, and to study the mitral inflow (diastolic function and mitral stenosis)
The apical 5 chamber view differs from the apical 4 chamber view by the presence of the aortic valve in the center of the image. This is the view where you will get the best alignement of your Doppler beam with the aortic outflow tract, to look and grade an aortic stenosis and to calculate the cardiac output.
The apical 2 chamber view will show you the anterior and inferior walls of the left ventricle.
In some ventilated patients, the subcostal view will be the only window accessible. You will be able to assess LV and RV function and valves regurgitations
From a subcostal approach, it is possible to obtain a short axis of the left ventricle, to estimate LV function, and a short axis of the aortic valve with visualization of the tricuspid and pulmonic valves.
Determination of the IVC diameter and respiratory variations are pivotal for the estimation of a patient's volume status.