Ventricular volume is reduced, the loops are shifted left. Again the cardiac cycle is trapped within the boundaries of the pressure-volume relationship. The total area enclosed by these loops is reduced reflecting a decrease in stroke work. The stroke volume is also decreased. The ventricular wall thickness is usually normal, it may be increased.
Ventricular filling is compromised by increased diastolic stiffness.
Once again the cardiac cycle is compressed, and the stroke work is reduced. Stroke volume is also decreased. If the stroke volume is decreased the heart rate must increase in order to maintain a normal cardiac output. Eventually, this compensatory effect will fail and cardiac output will fall. This is summarized in Table 1.