For studying Left Ventricular Outflow Tract flow by Color Doppler, the apical five chamber position is the best choice. In this position, the flow is almost parallel to the ultrasonic beam. It is also possible to use the left parasternal approach, the long axis of the heart.

Normally, the flow in the outflow tract of the left ventricle occurs in the systole phase and is directed towards the aorta.

If examining from Apical 5 Chamber View, The flow is directed away from the transducer accordingly encoded in blue color.

The flow will almost always exceed the Nyquist limit and is similar to the flow in the opposite direction (Spectrum Distortion).

 

Apical 5 Chamber view. LVOT flow Color Doppler. Simulation By Echocardiography Online Simulator MyEchocardiography.com

 

When examining from a parasternal approach, the long axis of the heart, the flow in the left ventricular outflow tract can be directed towards the transducer or away from the transducer. This depends on the orientation of the outflow tract to the ultrasound beam. If the outflow tract is in front of the transducer, then the flow is directed towards the transducer and is accordingly coded in red color. When positioned at the back, the flow is directed away from the transducer and is coded in blue color.

Parasternal view Long axis. LVOT flow Color Doppler. Simulation By Echocardiography Online Simulator MyEchocardiography.com

 

 

How to Simulate LVOT flow Color Doppler?

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