Talk:Ejection fraction

Move to left ventricular ejection fraction?

Is it time to move this to left ventricular ejection fraction, with a redirect from ejection fraction? Hugh2414 18:46, 20 Sep 2004 (UTC)

Though the term most often refers to the left ventricular value, ejection fraction equally applies to the right ventricle, no? --David Iberri (talk) 00:48, 15 February 2006 (UTC)

I've mentioned both RV and LF ejection fractions in the article, noting that when not qualified, EF usually refers to LVEF. Cheers, David Iberri (talk) 05:04, 19 February 2006 (UTC)

Leslie Beben chiming in. EF is probably a good estimate of the work efficiency of electrical and mechanical systole. EF lends itself readily to mathematical derivations of stroke volume. The difference between end diastolic volume and end systolic volume is readily applied to both SV and EF. minV vs. maxV are described as similar variables of myocardial work. Echocardiography has allowed an inexpensive and noninvasive means of illuminating the math in myocardial work. Carried a step further, one can appreciate that the inverse of EF is the difference between end systolic volume and end diastolic volume. This represents the injection fraction (IF). IF is probably a good estimate of diastole and the subject of another submission. —Preceding unsigned comment added by 24.211.109.44 (talk) 02:19, 14 October 2007 (UTC)

Agree that LVEF is a better term than EF as long as one acknowledges the implied application of RVEF, perhaps best elaborated as a pulmonary determinant of myocardial performance. —Preceding unsigned comment added by Lbeben (talk • contribs) 03:37, 21 October 2007 (UTC)

Imagine we Wikify EF to something most people can understand for the encyclopedia. To better appreciate this one needs to step back within the encyclopedic framework allowed and examine the more ancient term of Systole. As we seek to explain the workings of Systole, EF becomes a useful mathematical term to describe measurement of blood volume in varying stages of the Cardiac Cycle.

A ventricle is a hollow biomechanical pumping machine within the chest with the singular purpose of sending blood north, south and all points in between. For reasons we still do not fully understand, the heart knows how to direct blood to the end organ that needs it most under constantly variable physiologic demand. The ventricle is coded with an astonishing capability for phosphorylation of ATP unlike almost all other tissues. The explosive charge that ATP phosphorylation adds to Systole is mathematically absent from the work for reasons unclear. One is born with a left bucket ventricle and a right bucket ventricle. Throughout life the left bucket pumps blood to the body and brain. The brain usually decides how much of the load to send to each organ, muscle or other recipient depending upon if one is sleeping, just had a big meal or being chased by an angry bear. Meanwhile, the right bucket pumps blood into the lungs at a much lower pressure and oxygen saturation than the left sided circuit. Your right bucket is much thinner and wraps about halfway around and piggybacks on your left bucket. Averaged and balanced in health, the two buckets both generally empty and receive about 50% of the blood within them within several heart cycles. Medical imaging is the modern day equivalent to X-Rays from a bygone age. Medical imaging can very accurately measure the volume of the blood ejected out of the heart by measuring the amount of blood in the two ventricles in cubic centimeters. Medical imaging can show these volumetric measurements in real time. Means of imaging of this volume are legion and always proprietary. Two screenshots are necessary for the essential mathematics. The first is the ventricle folded and contracted down in shape as far as possible, the ancient term for this wringing of blood from the ventricle is Systole. The second shot occurs as the ventricle is filled and engorged with as much blood as possible, the opposing term for this is Diastole. The difference between the two screenshots represents a simple ratio that corresponds well to performance of the ventricle. The blood volume ejected from the left bucket feeding the brain and body (the periphery) is the Left Ventricular Ejection Fraction, or LVEF. The blood volumetric ejected from the right bucket into the lungs is the Right Ventricular Ejection Fraction or RVEF. The sum of LVEF + RVEF = Ejection Fraction or EF.

EF is a noble volumetric mathematical construct but incomplete without more constructs. Shovel ready similar constructs exist for contractility, compliance, length/tension relationships, angular velocity and probably Hooke's Law. — Preceding unsigned comment added by 75.176.131.225 (talk) 00:08, 4 February 2014 (UTC)

Problems with EF

I am suprised there is nothing in here about abnormalities in regards to EF and problems that result from those high/low EF. —Preceding unsigned comment added by 98.85.140.145 (talk) 00:59, 3 August 2010 (UTC)

Low EF has been extensively addressed. High EF seems less well understood. In my experience EF >70% represents a healthy female > 70 years of age with grade one diastolic dysfunction. This adaptation is not necessarily pathologic.

Normal Values

"The QT interval as recorded on a standard Electrocardiogram is generally agreed to be an exemplary display of depolarization of the ventricles. Widening of the QT interval is a reliable and inexpensive method in determination of mismatched flow states between the RV and LV."

This paragraph seems to be a complete non sequitur in this section. Perhaps someone knowledgeable can delete or amend it.154.5.40.122 (talk) 14:50, 22 November 2011 (UTC)

The QT interval is broad and includes both systolic and diastolic performance phases. Halved, the QS interval defines electrical depolarization Systole of the heart while the ST interval defines electrical repolarization Diastole.

Minimum EF to sustain life

I understand the normal range of EF is 50% to 70%, however, i'm not quite sure what the lowest EF that can sustain a human life, according to some non-official sources, i have found that the min EF that a live human would be around 8% or 9%, however this cannot be validated since these would probably very sick patients, who were probably on death's doorstep. however for research purposes, i will post this number here as a reference that will not be clinically tested. — Preceding unsigned comment added by Zhenny (talk • contribs) 02:31, 23 March 2013 (UTC)

You ask an important question. The age and condition of an individual seeking heart transplantation always implies an EF less than 20%.

Recent edits added to problems

In places this article reads like a patient information leaflet, which has made a problematic article worse. Whoever added things like "talk to your doctor about..." needs to read wp:MEDMOS. Lesion (talk) 02:08, 10 April 2013 (UTC)

Reorganization

While there isn't a section in wp:medmos on things like ejection fraction (which is what, physiology? medical phenomena?), i propose the following structure for this page, based on extension from the outlines for "Signs or symptoms" and "Medical tests":

• Top/Overview/Intro
• Medical uses
• Physiology
  • Normal values
  • Physics
• Clinical significance, with pathophysiology
• History
• Other animals

I'll work towards reorganizing with this in mind. Other's input appreciated.

BakerStMD T|C 15:36, 18 January 2015 (UTC)

I have a draft at user:Bakerstmd/Ejection fraction. Please leave your comments on that draft here. BakerStMD T|C 22:57, 18 January 2015 (UTC)

Heart failure categories section

What is "(Table [null 3.1])"? --Guy Macon (talk) 23:49, 15 May 2018 (UTC)

Definition of Ejection Fraction

In the first sentence Ejection fraction is defined as "the volumetric fraction (or portion of the total) of fluid (usually blood) ejected from a chamber (usually the heart) with each contraction (or heartbeat)." I think this definition is very misleading, as it is not the portion of the TOTAL blood, it is the portion of the AMOUNT LEFT OVER in the ventricle. The denominator in the fraction is the End Diastolic Volume, not the total blood in the ventricle pre-systole, e.g. at an ejection fraction of 50%, if the stroke volume is 50 arbitary units, and the end diastolic volume is 100 arbitary units, then 50 units were ejected leaving 100 units left, then originally there was 150 units of blood in the ventricle in the moments before contraction.

This is a common mistake. — Preceding unsigned comment added by 94.175.24.89 (talk) 01:23, 24 January 2020 (UTC)

Wiki Education assignment: Technical and Scientific Communication

This article was the subject of a Wiki Education Foundation-supported course assignment, between 22 August 2022 and 9 December 2022. Further details are available on the course page. Student editor(s): Ftaylor4 (article contribs).

— Assignment last updated by Ftaylor4 (talk) 23:53, 20 September 2022 (UTC)

Two recent comments

On June 13, 2023, @Lbeben: added the below unsigned statement to #Reorganization above.

I'll attempt to explain. Ejection fraction is a mathematical puzzle of physiology and medical phenomena regarding how a human heart pumps 60-80 times per minute for 80 years.

And on June 16, 2023, Lbeben added the below unsigned statement to #Minimum EF to sustain life.

Math nerd; shouldn't the most common calculations for ejection fraction be free sourced on Wikipedia to anyone interested in heart failure?

I've removed them from those old postings, but since they do seem to be about the topic of the article, added them back here. SchreiberBike | ⌨  20:06, 17 June 2023 (UTC)

Schreiber Bike this is essentially pure mathematics. Why should theory be subject to any license or patent? lbeben 03:21, 25 June 2023 (UTC)