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An ejection fraction (EF) is the volumetric fraction (or portion of the total) of fluid (usually blood) ejected from a chamber (usually the heart) with each contraction (or heartbeat). It can refer to the cardiac atrium , [ 1 ] ventricle , [ 2 ] gall bladder, [ 3 ] or leg veins, [ 4 ] although if unspecified it usually refers to the left ...
Myocardial infarction or cardiomyopathy causes damage to the myocardium, which impairs the heart's ability to eject blood and, therefore, reduces ejection fraction. This reduction in the ejection fraction can manifest itself as heart failure. Low EF usually indicates systolic dysfunction, and severe heart failure can result in EF lower than 0.2 ...
In cardiovascular physiology, stroke volume (SV) is the volume of blood pumped from the ventricle per beat. Stroke volume is calculated using measurements of ventricle volumes from an echocardiogram and subtracting the volume of the blood in the ventricle at the end of a beat (called end-systolic volume [note 1]) from the volume of blood just prior to the beat (called end-diastolic volume).
SVs are also used to calculate ejection fraction, which is the portion of the blood that is pumped or ejected from the heart with each contraction. To calculate ejection fraction, SV is divided by EDV. Despite the name, the ejection fraction is normally expressed as a percentage.
Heart failure with preserved ejection fraction (HFpEF) is a form of heart failure in which the ejection fraction – the percentage of the volume of blood ejected from the left ventricle with each heartbeat divided by the volume of blood when the left ventricle is maximally filled – is normal, defined as greater than 50%; [1] this may be measured by echocardiography or cardiac catheterization.
The resulting images show that the volumetrically derived blood pools in the chambers of the heart and timed images may be computationally interpreted to calculate the ejection fraction and injection fraction of the heart. The Massardo method can be used to calculate ventricle volumes. This nuclear medicine scan yields an accurate, inexpensive ...
It is relatively straightforward to estimate the volume of a healthy, filled left ventricle by visualizing the 2D cross-section with cardiac ultrasound. [2] This technique is less helpful for estimating right ventricular preload because it is difficult to calculate the volume in an asymmetrical chamber. [ 2 ]
From these, it is easy to calculate the area (in cm 2) of the aortic valve by simply dividing the LV stroke volume (in cm 3) by the AV VTI (in cm) measured on the spectral Doppler display using continuous-wave Doppler. [citation needed] Stroke volume = 0.785(π/4) x Diameter 2 x VTI of LVOT Cross sectional area of LVOT = 0.785(π/4) x LVOT ...