Pressure-Volume Diagram During the Cardiac Cycle
Changes in Ventricular Volume and Pressure During Different Events in the Cardiac Cycle
Ventricular Filling
Volume: Rise
Pressure: Initial slight fall and then a slight rise
Isovolumetric Contraction
Volume: No change
Pressure: Sharp rise
Ejection
Volume: Falls
Pressure: Initial rise and then fall
Isovolumetric Relaxation
Volume: No change
Pressure: Sharp fall
Pressure-Volume Loop
The area covered by the pressure-volume loop represents the net external work output of the ventricle.