Points
The optimal performance of the left ventricle depends on its ability to cycle between two states: A compliant chamber in diastole that allows the left ventricle to fill from low LA pressure. A stiff chamber (rapidly rising pressure) in systole that ejects the stroke volume at arterial pressures.
The ventricle has two alternating functions: systolic ejection and diastolic filling. Furthermore, the stroke volume must increase in response to demand, such as exercise, without much increase in LA pressure.
Elevated filling pressures are the main physiologic consequence of diastolic dysfunction. Filling pressures are considered elevated when the mean pulmonary capillary wedge pressure (PCWP) is >12 mmHg or when the LVEDP is >16 mmHg. Filling pressures change minimally with exercise in healthy subjects. Exercise-induced elevation of filling pressures limits exercise capacity and can indicate diastolic dysfunction.