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Parasternal Short-Axis Echocardiogram View

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Parasternal Short-Axis Echocardiogram View, PSAX View

  • Technique
  • Transducer
  1. Transducer orientation (start)
    1. Transducer Rotated 90 degrees clockwise from Parasternal Long Axis View
    2. Transducer 3-5 cm to the left of the left sternal border at 3rd to 5th intercostal space
    3. Transducer indicator pointed towards patient's left Shoulder (1:00 position)
  2. Images
    1. ultrasoundHeartPLAXandPSAX.jpg
    2. ultrasoundProbePositionEchoPSAX.jpg
    3. ultrasoundProbePositionEchoPSAX_apical.jpg
  3. Transducer gradually tilted down heart axis to obtain 4 heart cross-sectional slices
    1. Aortic valve level (may require sliding up a rib space)
      1. echo_psax_aorta.png
    2. Mitral valve level
      1. echo_psax_mitral.png
    3. Mid-ventricle level
      1. echo_psax_LV.png
    4. Heart apex (may require sliding down a rib space)
  • Technique
  • Landmarks
  1. Landmarks: Aortic valve level
    1. Right ventricular outflow tract
    2. Tricuspid valve, aortic valve (peace or mercedes sign when tri-leaflet) and pulmonic valve
    3. Right atrium, left atrium and pulmonary artery
    4. Right and left main Coronary Artery origins may be visualized just cephalad to the aortic level
    5. Color Flow, pulse wave and Continuous Wave Doppler may be used for Tricuspid insufficiency and Pulmonic Insufficiency
    6. ultrasoundBMP_cvPSAX_aorta2.jpg
  2. Landmarks: Mitral valve level
    1. Right ventricle
    2. Mitral valve (anterior and posterior leaflets appear as a fish mouth opening and closing)
    3. Left ventricle should be round (not an oblong oval); rotate the probe until round
    4. Mitral Valve area may be estimated by planimetry (drawn boundary of open valve)
    5. ultrasoundBMP_cvPSAX_MV2.jpg
  3. Landmarks: Mid-ventricle level (most useful short axis view for emergency department)
    1. Allows for observation of ventricular wall motion and overall contractility, as well as comparison of RV vs LV diameter
    2. Right ventricle
    3. Septum
    4. Left ventricle (with trabeculations representing papillary Muscles)
      1. Mnemonic: SALI (from Richie Palma, who calls the LV on PSAX, his girlfriend "Sally")
      2. From the Septum, rotating clockwise: S-Septum, A-Anterior, L-Lateral, I-Inferior
  4. Landmarks: Apical level
    1. Right ventricle (much smaller in size than left ventricle unless right ventricle dilated)
    2. Left ventricle (apical wall motion evaluation)
    3. ultrasoundBMP_cvPSAX_apex.jpg
  • Interpretation
  1. Bicuspid aortic valve (Aortic valve level)
    1. Bicuspid valve is visualized with valve open (since bicuspid valve has a fused valve leaflet that is not evident in closed position)
    2. Tri-leaflet appearance (Mercedes symbol) will be seen in both bicuspid and tricuspid valve when valve closed
  2. Left ventricle wall motion abnormality (mid-ventricle level)
    1. Best view to see all left ventricle walls
  • Resources
  1. Parasternal Short Axis View Video (SonoSite)
    1. http://www.youtube.com/watch?v=EaLuCBXXINg
  2. Echocardiographer
    1. http://echocardiographer.org/
  • References
  1. Palma, Bourque and Jordan (2019) Introduction to Adult Echo Ultrasound Conference, GulfCoast Ultrasound, St. Petersburg
  2. Mateer and Jorgensen (2012) Introduction and Advanced Emergency Medicine Ultrasound Conference, GulfCoast Ultrasound, St. Pete's Beach
  3. Noble (2011) Emergency and Critical CareUltrasound, Cambridge University Press, New York, p. 61-88
  4. Orman, Dawson and Mallin in Majoewsky (2013) EM:Rap 13(1): 4-6
  5. Reardon (2011) Pocket Atlas Emergency Ultrasound, McGraw Hill, New York, p. 61-106