Injection fraction
Encyclopedia
Injection fraction, or end diastolic volume (EDV) divided by end systolic volume (ESV) of the ventricles or IF=EDV/ESV, is the inverse mathematical operation of the Myocardium derived Ejection Fraction
Ejection fraction
In cardiovascular physiology, ejection fraction is the fraction of Blood pumped out of the Right Ventricle of the heart to the Pulmonary Circulation and Left Ventricle of the heart to the Systemic Circulation with each Heart beat or Cardiac cycle...

. "Ejection Fraction" is historically and mathematically derived from Cardiac Output
Cardiac output
Cardiac output is the volume of blood being pumped by the heart, in particular by a left or right ventricle in the time interval of one minute. CO may be measured in many ways, for example dm3/min...

 first posited by Adolph Fick 1829-1901. Ejection fraction (EF) is most readily appreciated as the difference between End-systolic volume
End-systolic volume
End-systolic volume is the volume of blood in a ventricle at the end of contraction, or systole, and the beginning of filling, or diastole.ESV is the lowest volume of blood in the ventricle at any point in the cardiac cycle....

 and End-diastolic volume
End-diastolic volume
In cardiovascular physiology, end-diastolic volume is the volume of blood in the right and/or left ventricle at end Load or filling in . Because greater EDVs cause greater distention of the ventricle, EDV is often used synonymously with preload, which refers to the length of the sarcomeres in...

. The utility of this volumetric measurement of systolic function of the heart is now inexpensively and clinically replicated worldwide. Mathematical derivation as stroke volume
Stroke volume
In cardiovascular physiology, stroke volume is the volume of blood pumped from one ventricle of the heart with each beat. SV 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 from the volume...

 and minimum volume or MinV similarly apply as determinants of Systole
Systole (medicine)
Systole is the contraction of the heart. Used alone, it usually means the contraction of the left ventricle.In all mammals, the heart has 4 chambers. The left and right ventricles pump together. The atria and ventricles pump in sequence...

. Ejection Fraction is noninvasively and inexpensively reproduced echocardiographically in many languages as EF=(EDV-ESV)/EDV. Extrapolated to a single chamber of known dimensions this calculation may be simplified to (LV and RV) EF=ESV/EDV. Q is another attractive mathematical construct of Systole.

Volumetric determinants of diastole
Diastole
Diastole is the period of time when the heart fills with blood after systole . Ventricular diastole is the period during which the ventricles are relaxing, while atrial diastole is the period during which the atria are relaxing...

 implies an inverse mathematical approach to the published work of Adolph Fick. Injection fraction as a volumetric determinant of Diastole
Diastole
Diastole is the period of time when the heart fills with blood after systole . Ventricular diastole is the period during which the ventricles are relaxing, while atrial diastole is the period during which the atria are relaxing...

 is the difference between end diastolic volume (EDV) and end systolic volume (ESV)of the ventricles. IF=EDV/ESV or IF=(ESV-EDV)/ESV. Decline of injection fraction implies a measurable volumetric determinant of diastolic heart failure to the extent that decline of Right and Left EF heralds Systolic Heart Failure. Decline of IF probably closely follows clinically relevant time ratios such as E:A intervals across the mitral valve. Tissue Doppler Echocardiography appears similarly useful in identifying pathologic regional wall motion as a signature of diastolic dysfunction.

It can be measured with a MUGA scan
MUGA scan
A MUGA scan is a time-proven yet dated nuclear medicine test designed to evaluate the function of the right and left ventricles of the heart, thus allowing informed diagnostic intervention in heart failure. It is also called radionuclide angiography, as well as gated blood pool imaging...

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