Changes

Heart failure can be further classified according to the cause, whether it leads predominantly to underperfusion or congestion (forward or backward failure) and whether the right or left side of the circulation is affected to a greater extent (right-sided failure or left-sided failure). In some cases, biventricular failure may occur.  

Heart failure can be further classified according to the cause, whether it leads predominantly to underperfusion or congestion (forward or backward failure) and whether the right or left side of the circulation is affected to a greater extent (right-sided failure or left-sided failure). In some cases, biventricular failure may occur.  

* '''Forward failure''' (cardiogenic shock): underperfusion of the arterial circulation at normal pressure

* '''Forward failure''' (low output failure/cardiogenic shock): underperfusion of the arterial circulation at normal pressure

* '''Backward failure''' (congestive heart failure): adequate output at abnormal pressures, too much fluid in the venous circulation

* '''Backward failure''' (congestive heart failure): adequate output at abnormal pressures, too much fluid in the venous circulation