In significant mitral stenosis, the velocity and pressure gradient across the aortic valve are typically described as which?

• A. Falsely diminished
• B. Falsely elevated
• C. Unchanged
• D. Not measurable

Answer: (A)

In significant mitral stenosis, forward flow into the aorta is reduced because the left ventricle receives less blood during diastole and cannot eject as much with each beat. Doppler measurements of the aortic valve depend on that forward flow, so peak velocity and the pressure gradient across the aortic valve tend to be lower than you would expect given the valve’s intrinsic characteristics. In other words, the measured velocity and gradient are falsely diminished because the overall stroke volume is diminished by the mitral lesion. This is why the best description is that the aortic valve velocity and gradient appear reduced even if there isn’t a change in the aortic valve itself. The other options don’t fit because the flow isn’t increased or unchanged; it’s reduced, and the measurements are still obtainable, just lower than they would be with normal or higher flow.