Isotopes are atoms of the same element (that is, with the same number of protons in their atomic nucleus), but having different numbers of neutrons. Most (66 of 94) naturally occurring elements have more than one stable isotope.here are 80 elements that have at least one stable isotope and 38 that have exclusively radioactive isotopes, which decay over time into other elements. Iron is the most abundant element (by mass) making up the Earth, while oxygen is the most common element in the crust of the earth.
This test, often called an echo, shows your heart's movement. During this exam, your doctor places a wand on the surface of your chest. It sends ultrasound waves that show pictures of your heart's valves and chambers. Those images let your doctor look at how well your ticker is pumping. Your doctor may combine an echocardiogram with tests called Doppler ultrasound and color Doppler to check blood flow across your heart's valves. Ejection fraction (EF). It's a measure of how much blood is pumped out of your heart each time it beats.
What Is Ejection Fraction? Ejection fraction, or EF, is a measurement that indicates how well your heart is functioning. This number tracks how much blood your heart is pumping out with each contraction. Your ejection fraction is described as a percentage. If youâre healthy, your ejection fraction is generally between 55% and 70%. For instance, an ejection fraction of 60% means your heart is pumping 60% of your blood out of your left ventricle (its main pumping chamber) every time your heart beats. What Is Low Ejection Fraction? Low ejection fraction, sometimes called low EF, is the term we use to describe your ejection fraction if it falls below 55%. It means your heart isnât functioning as well as it could. If a diagnostic test indicates that you have low ejection fraction, your doctor will want to thoroughly check you for a heart condition. If you get to a 35% ejection fraction or below, you are at high risk of developing a dangerous arrhythmia and going into heart failure.