1: Measure the LVOT diameter in centimeters.
The optimal view is a maximally zoomed view of the
midesophageal AVLAX. The gain and compress should
be set so the endomyocardial wall of the LVOT is clearly
discernable. Freeze the display and use the trackball
to cycle thru the cardiac cycle to the mid-ejection
period when the LVOT is at it's maximal diameter.
Using the calipers, measure from intimal wall to intimal
wall just proximal to the aortic valve. Activate the
Aortic Valve analysis package and select LVOT diameter
and enter the value of the LVOT diameter.
2: Obtain a pulse wave doppler of the LVOT.
The optimal view is the deep transgastric AVLAX view
or the transgastric AVLAX view. The former view is
preferable if obtainable. Once the view is obtained
turn on the PWD and use the track ball to move the
PWD line to the LVOT and place the sample volume just
proximal to the aortic valve. The sample volume should
be at the same location where the LVOT diameter was
measured. A doppler profile of the LVOT should be
displayed with normal velocities in the LVOT. If a
poor or low velocity doppler wave form is displayed
reposition the view and move the PWD line thru out
the LVOT. The PWD must be parallel to the LVOT jet
to pick up the maximal velocity and obtain a good
doppler wave form. After a good doppler wave form
is obtained look at the morphology and the maximal
velocity of the waveform and note it. Using the tracing
feature, use the trackball and trace the doppler profile.
Once traced, a VTI of the tracing will be calculated.
This activity has been planned and implemented in accordance with the accreditation requirements and policies of the Accreditation Council for Continuing Medical Education through the joint providership of University of Nebraska Medical Center, Center for Continuing Education and JLS Interactive, LLC.
The University of Nebraska Medical Center, Center for Continuing Education is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.
This activity is approved by the American Society of Radiologic Technologists (ASRT) as sonography-related continuing education (CE). Credit(s) issued for successful completion of ASRT-approved CE activities are accepted by the American Registry of Diagnostic Medical Sonography, American Registry of Radiological Technologists, Cardiovascular Credentialing International and Canadian Association of Registered Diagnostic Ultrasound Professionals. Contact the applicable registry for additional information / restrictions on their acceptance of ASRT CE credit.