• During the Valsalva maneuver, the intrathoracic pressure increases, which reduces the venous return to the heart. This reduces the left ventricular (LV) preload and consequently reduces the trans- mitral filling velocities. In a healthy adult, early passive filling (E-wave) decreases more than the A-wave. Therefore, E/A ratio decreases. Even in grade 1 diastolic dysfunction E/A is < 1.

• The Valsalva maneuver reduces the preload, so both the E- and A-wave velocities generally decrease.

• In a pseudonormal filling pattern, the resting mitral inflow may appear normal because the elevated left atrial pressure increases the E-wave velocity. At baseline: E/A= 1 to 1. 5. During the Valsalva maneuver, the preload and the left atrial pressure decrease. This unmasks the underlying impaired LV relaxation. As a result, the E-wave velocity decreases significantly, A-wave becomes relatively dominant, E/A ratio decreases and may reverse.

• In grade III (severe / restrictive diastolic dysfunction), the E/A ratio becomes significantly elevated, typically > 2. This happens because the high filling pressure in the left atrium forces a large volume of blood into the ventricle during early diastole (high E-wave), while the late atrial contraction is restricted by the high pressure (small A-wave). Valsalva maneuver can be used to differentiate, as it temporarily reduces the high E/A ratio.

Hence, the correct answer is option ‘d’.

References:

1. Mitter SS, Shah SJ, Thomas JD. A test in context: E/A and E/e' to assess diastolic dysfunction and LV filling pressure. J Am Coll Cardiol 2017;69:1451-64.