Transducer Position: By tilting the head of the probe upwards you move to more anterior structures and create the apical 5 chamber position, the LVOT, aortic valve and proximal aorta can be seen. It is called the 5 chamber view because the ascending aorta is now also seen in addition to the two ventricles and two atria.
Note that with the probe tilted anteriorly the ultrasound beam place slices through the aortic valve and aortic root.
AV - aortic valve, RV - right ventricle, LV - left ventricle, RA - right atrium, LA - left atrium, MV - mitral valve, TV - tricuspid valve
A ideal 5 chamber view
This is a useful view for evaluating aortic stenosis and regurgitation, and allows Doppler assessment of gradients across the aortic valve in aortic stenosis and measurement of deceleration slopes in aortic regurgitation. It is also good for the evaluation of the LVOT gradient as seen in cases of hypertrophic cardiomyopathy for example. Given that angulation is more anterior, the portion of the septum now visualized in this view is the anteroseptum. Ao - aortic root, RV - right ventricle, LV - left ventricle, RA - right atrium, LA - left atrium.
Color Doppler across the Aortic Valve
It is important to assess for aliasing flow as there may be flow acceleration in the LVOT. When seen, aortic regurgitation is commonly overestimated in this view and hence it is not typically used in quantification assessment. The quantification of aortic regurgitation and stenosis are discussed elsewhere. The above video shown normal color Doppler profile across the aortic valve.
To better assess the aortic valve and for the presence of stenosis and regurgitation, color Doppler and spectral Doppler are used.
Spectral Doppler of the Aortic Valve
Pulse wave Doppler at the LVOT (left picture) usually gives a peak velocity near 1 meter/second in most individuals. Using Continuous Wave Doppler across the aortic valve (right picture) if there is a significantly higher peak velocity then this suggests aortic stenosis.