Overview

Heart failure with preserved ejection fraction (HFpEF) is a type of heart failure. It happens when the heart's lower left chamber (left ventricle) pumps out less blood than the body needs.

It's sometimes called diastolic heart failure. This is because your left ventricle is not able to fill properly with blood during the diastolic (filling) phase. So the amount of blood pumped out to the body is less than normal. The ventricle can pump well. But it may be stiff so it can't relax and fill with blood as well as it should.

To see how much blood inside the left ventricle is pumped out with each contraction, the ejection fraction is measured. The left ventricle squeezes and pumps some (but not all) of the blood in the ventricle out to your body.

A normal ejection fraction is more than 55%. This means that more than 55% of the total blood in the left ventricle is pumped out with each heartbeat.

You may be diagnosed with HFpEF when the ejection fraction is 50% or more. Although the ejection fraction may be normal, the heart has less blood inside it to pump out.^{footnote 1, footnote 2}

What causes it?

There are many things that can lead to heart failure with preserved ejection fraction (diastolic heart failure). These causes can impair your left ventricle's ability to fill properly with blood during diastole.

For example, causes can include:

• Natural effect of aging. As you age, your heart muscle tends to stiffen. This can prevent your heart from filling with blood properly, leading to diastolic heart failure.
• Coronary artery disease. Coronary artery disease can narrow the arteries that supply blood to the heart. It can cause heart failure because of low blood flow to the heart muscle (ischemia), which can prevent the heart from relaxing and filling with blood.
• High blood pressure. High blood pressure is elevated pressure in your arteries. Heart muscle can thicken the wall of the heart (hypertrophy) in an effort to pump against high blood pressure. Thickened heart muscle limits the heart's ability to relax and fill with blood.

This is not a complete list of possible causes.