Which Doppler parameter is used to quantify the contraction velocity of the left atrial appendage?

Which Doppler parameter is used to quantify the contraction velocity of the left atrial appendage?

• A. Contraction velocity
• B. E velocity
• C. Mitral annulus velocity
• D. Pulmonary vein velocity

Answer: (A)

The key measurement is the left atrial appendage emptying (contraction) velocity. Using Doppler, clinicians place the sample volume at the LAA orifice during atrial systole to capture the rate at which the appendage contracts and ejects blood into the left atrium. This LAA contraction velocity directly reflects the mechanical function of the appendage and is a primary predictor of thromboembolic risk in conditions like atrial fibrillation; lower velocities indicate stasis and higher risk. E velocity refers to early diastolic mitral inflow and relates to LV filling, not LAA contraction. Mitral annulus velocity comes from tissue Doppler at the mitral annulus and assesses LV diastolic/systolic function, not the LAA. Pulmonary vein velocity measures flow from the veins into the left atrium and informs diastolic pressures, again not the LAA’s contraction.

The key measurement is the left atrial appendage emptying (contraction) velocity. Using Doppler, clinicians place the sample volume at the LAA orifice during atrial systole to capture the rate at which the appendage contracts and ejects blood into the left atrium. This LAA contraction velocity directly reflects the mechanical function of the appendage and is a primary predictor of thromboembolic risk in conditions like atrial fibrillation; lower velocities indicate stasis and higher risk.

E velocity refers to early diastolic mitral inflow and relates to LV filling, not LAA contraction. Mitral annulus velocity comes from tissue Doppler at the mitral annulus and assesses LV diastolic/systolic function, not the LAA. Pulmonary vein velocity measures flow from the veins into the left atrium and informs diastolic pressures, again not the LAA’s contraction.