 end-diastolic pressure, end-systolic pressure, ejection and filling intervals, contractility index, stroke volume, and ejection fraction).More importantly, other interesting parameters are derived from series of loops obtained under changing conditions.For example, the end-diastolic pressure-volume relationship (EDPVR) and end-systolic pressure-volume relationship (ESPVR) are derived from series of loops obtained by slowly inflating a balloon to occlude the inferior vena cava, a procedure that reduces cardiac preload.