The stats look normal, but blood flow is still low. Why?
If you are having symptoms like fatigue and shortness of breath with minimal physical activity, your doctor may consider heart failure. One of the numbers they’ll want to measure is something called ejection fraction. However, even if your ejection fraction comes back “normal,” you might still have heart failure. This type is known as heart failure with preserved ejection fraction.
Ejection fraction is the percentage of blood that gets pumped out of the left ventricle with each beat. The left ventricle is one of four chambers of the heart. It’s the last chamber that oxygen-rich blood goes through before dispersing throughout the body.
A healthy ejection fraction is around 50 to 70 percent. That means that about half of the blood in the left ventricle leaves with each beat. This ensures that the body’s organs get the oxygen and nutrients they need to function properly. When the ejection fraction is lower than 50 percent, the body might start to suffer from the low blood flow. (That’s called heart failure with reduced ejection fraction.)
What is heart failure with preserved ejection fraction?
Heart failure with preserved ejection fraction means that the ventricle doesn’t fully fill up with blood between each beat. Often, the walls of the left and right ventricle become stiff, enlarged, and swollen. This means there’s less volume for incoming blood, and also that the ventricle can’t properly relax between the beats. This type of heart failure accounts for about a third of heart failure patients.
Understanding preserved ejection fraction requires doing a little math. Finding the ejection fraction involves dividing the amount of blood pumped out by the total amount of blood that was in the ventricle before the pump.
With heart failure with preserved ejection fraction, the heart may still be pumping out 50 to 70 percent of the blood with each beat. However, there was less blood in the heart to begin with. This means blood flow is still low and the organs may not be getting the oxygen they need, despite a “normal” ejection fraction.
How is heart failure treated?
Treatment for heart failure with preserved ejection fraction includes:
- Sticking to your prescribed medicines (which may include diuretics to reduce water retention and blood pressure-lowering medicines)
- Eating a low-sodium diet
- Exercising regularly, especially going on regular walks
- Getting enough rest (but not too much)
- Not smoking
- Limiting or avoiding alcohol intake
When heart failure becomes more advanced, you may be eligible for additional treatments. This includes implanted devices that assist the heart or potentially surgeries. Luckily, the treatment options available today are better than they were just a few decades ago. That means many people are able to successfully slow the progression of their heart failure.
Marrick Kukin, MD, is a cardiologist at Lenox Hill Hospital, Northwell Health.