The reason for this is when a person initially stands, cardiac output and arterial pressure decrease (because right atrial pressure falls).

Therefore right atrial pressure also alters venous return.

Right heart catheterization - may show high left atrial pressure.

Pressure starts to increase, becomes rapidly higher than the atrial pressure, and the mitral valve closes.

This left atrial pressure is transmitted to the pulmonary vasculature and causes pulmonary hypertension.

"A clinical estimation model for noninvasive determination of atrial pressure in total artificial heart patients."

The pressures where there is a steep relationship lie within the normal range of right atrial pressure (RAP) found in the healthy human during life.

The eponymous Bainbridge reflex is named after him, which is an increased heart rate due to an increase of the right atrial pressure.

When the lungs become functional at birth, the pulmonary pressure decreases and the left atrial pressure exceeds that of the right.

Because of the large compliance of the pulmonary circulation, it provides an indirect measure of the left atrial pressure.