Algorithm

We are doing effective AVA which is usually small than the anatomic AVA

1. PLAX with mostly RCC (if both cusps equally, not max diameter) - yellow line

2. Measure at aortic valve base - yellow line

•  LVOT diameter measurement is a critical step in TTE assessment of AS.
• EACVI/ASE guidelines recommend measuring LVOT diameter 5-10 mm below annulus.
• However, this underestimates SV/AVA and overestimates AS severity and LF status vs PC-CMR.
• Measuring LVOT diameter at the annulus agrees best with PC-CMR SV and AVA measurements.

If there is a bar of calcium, need to measure from where you think the LVOT is not calcium

Dont measure the "hairs" or go past valve closure

Stroke Volume

• Calculate SVi by continuity equation but also corroborate by biplane volume method
• Biplane volume method correlates well to MRI
• Need to make sure not to forshorten apical

Other Tips

• Make sure patient is normotensive

• Valve should look abnormal to consider severe AS

• Confirm AVA with DVI - if DVI very normal then suspect could be error with AVA measurement

• Look at old LVOT measurments or predicted LVOTD

• If they are small, use AVAi and cuttoff 0.6

LFLGAS