A false reduction of PHT tends to cause which outcome?

A false reduction of PHT tends to cause which outcome?

• A. Underestimated stenosis
• B. Overestimated stenosis
• C. Underestimated valve area
• D. Overestimated LV function

Answer: (A)

PHT in mitral stenosis is used to estimate the valve area, with MVA ≈ 220 divided by the pressure half-time. Because the relationship is inverse, a shorter (falsely reduced) PHT leads to a larger calculated valve area. A larger calculated valve area makes the stenosis appear milder than it really is, so the outcome is an underestimation of stenosis severity. If PHT were longer instead, you would trend toward overestimating stenosis. Factors that can bias PHT (heart rate, LV compliance, rhythm, etc.) can affect this estimate, so interpretation should consider these potential influences.

PHT in mitral stenosis is used to estimate the valve area, with MVA ≈ 220 divided by the pressure half-time. Because the relationship is inverse, a shorter (falsely reduced) PHT leads to a larger calculated valve area. A larger calculated valve area makes the stenosis appear milder than it really is, so the outcome is an underestimation of stenosis severity. If PHT were longer instead, you would trend toward overestimating stenosis. Factors that can bias PHT (heart rate, LV compliance, rhythm, etc.) can affect this estimate, so interpretation should consider these potential influences.