What is ventricular Elastance?
In other words, a stronger ventricle will achive greater stiffness (i.e. greater maximal elastance) than a weak ventricle. The slope of a line through the end-systolic pressure-volume point (the left upper corner of the P-V loop) is termed End-Systolic Elastance (Ees) and is a measure of ventricular contractility.
How do you calculate ventricular Elastance?
The noninvasive assessment of E LVI is based on the equation: E LVI = (end-systolic pressure/end-systolic volume index – V 0) and assumes that V 0 (the theoretical volume when no pressure is generated) is negligible compared with end-systolic volume. The E aI can be calculated as end-systolic pressure/stroke volume.
What is Emax heart?
Emax is defined as the slope of the end-systolic pressure-volume relation, which is relatively linear within the normal working range of the left ventricle.
What is dynamic arterial Elastance?
Dynamic arterial elastance (Eadyn), the ratio between arterial pulse pressure and stroke volume changes during respiration, has been postulated as an index of the coupling between the left ventricle (LV) and the arterial system.
What is Eadyn?
Background. Dynamic arterial elastance (Eadyn), defined as the ratio between pulse pressure variations and stroke volume variations, has been proposed to assess functional arterial load.
What is Espvr?
The ESPVR is the relation between pressure and volume in the left or right ventricle when the myocardium reaches its maximum state of activation near end-systole (2,3).
What is ventricular arterial coupling?
VA coupling characterizes the interaction between the myocardial contractile function and the load opposed by the arterial circulation. This interaction defines the cardiovascular performance and efficiency and can be analytically defined by relating ventricular and arterial elastances.
What is preload and afterload?
Preload is the initial stretching of the cardiac myocytes (muscle cells) prior to contraction. It is related to ventricular filling. Afterload is the force or load against which the heart has to contract to eject the blood.
What increases preload and afterload?
Increased aortic pressure, which increases the afterload on the ventricle, reduces stroke volume by increasing end-systolic volume, and leads to a secondary increase in ventricular preload.
What is pulse pressure variation?
Pulse pressure variation (PPV), which quantifies the changes in arterial pulse pressure during mechanical ventilation, is one of the dynamic variables that can predict fluid responsiveness.