The mean gradient is derived from which data?

The mean gradient is derived from which data?

• A. Velocities Across the Flow
• B. Diastolic Pressures Only
• C. Systolic Pressures Only
• D. End-Systolic Volumes

Answer: (A)

The mean gradient across a valve is calculated from the velocity data across the flow. The connection comes from the Bernoulli relationship: the pressure drop across a stenotic valve is related to how fast blood is moving through it. By measuring the velocity across the valve (usually with Doppler), you can convert that velocity into pressure differences using ΔP ≈ 4v^2, then average those instantaneous gradients over the cardiac cycle to obtain the mean gradient. Plain systolic or diastolic pressures alone don’t capture the varying pressure drop across the valve, and end-systolic volumes reflect chamber size rather than flow-driven pressure changes.

The mean gradient across a valve is calculated from the velocity data across the flow. The connection comes from the Bernoulli relationship: the pressure drop across a stenotic valve is related to how fast blood is moving through it. By measuring the velocity across the valve (usually with Doppler), you can convert that velocity into pressure differences using ΔP ≈ 4v^2, then average those instantaneous gradients over the cardiac cycle to obtain the mean gradient. Plain systolic or diastolic pressures alone don’t capture the varying pressure drop across the valve, and end-systolic volumes reflect chamber size rather than flow-driven pressure changes.