Welcome to the VR community. Without more information, I don't think anyone can offer more than suggestions. Do you know the area of your valve in square centimeters and the measures of the pressure gradient across the valve? Those are likely to give some indication as to whether you might be experiencing symptoms of the valve stenosis. As Al mentioned, inner ear problems are much more likely to be causing your balance problems, especially, if you notice that moving your head in a particular direction initiates the vertigo. For example, BPV (benign positional vertigo) is a problem I've experienced which caused dizziness when I moved my head to the upper right and frequently occured when I got out of bed. It is usually treated easily with out drugs or surgery. Ask your family Doctor to check you out.
Larry