What is one consequence of excess fluid in the pericardial sac?

Excess fluid in the pericardial sac can lead to a condition known as pericardial effusion. When there is an accumulation of fluid, it can exert pressure on the heart, particularly impacting its ability to fill adequately during diastole.

Decreased diastolic filling occurs because the fluid in the pericardial sac restricts the heart's normal movement. The heart has a limited capacity to expand when fluid surrounds it, thereby reducing the volume of blood that can enter the ventricles when they relax. As a result, this leads to a decline in stroke volume and, consequently, reduces overall cardiac output.

This physiological response to excess fluid explains why decreased diastolic filling is a notable consequence of pericardial effusion, highlighting its significant impact on cardiac function.