What's Your Ejection Fraction?  Heart Patients Need to Know 
(Posted 2/27/07) 

Numbers are a part of life, from your address, phone number and driver's license to your health-related numbers like your blood pressure and cholesterol. 

But there's an important number for your heart health that tends to get overlooked:  It's your EF number. 

EF means "ejection fraction," and it's the percentage of blood that is squeezed or ejected out of the heart's left ventricle during each beat.  Like cholesterol and blood pressure, it's a key indicator of your heart health.  

During National Heart Month, the Genesis Heart Institute urges those with heart disease and those at high risk for heart disease to know their EF.  A normal ejection fraction is 55-65 percent.  An EF of less than 40 percent indicates that the heart muscle has been damaged and is not functioning properly. 

"Ejection fraction is one of the most important factors of cardiac morbidity and mortality," said electrophysiologist Blair foreman, M.D., of Cardiovascular Medicine, P.C.  "When heart function declines, the heart is less able to pump the blood necessary to meet the demands of the body.  The result is a rise in pressure within the heart and lungs, leading to breathlessness, fluid retention and symptoms of fatigue and malaise.  The primary concern of a low EF is the known correlation with Sudden Cardiac Arrest."  

Knowing your EF and seeking treatment if it's not at a safe level can help reduce the risk of Sudden Cardiac Arrest, a condition that claims more than 335,000 American lives each year. 

"People know their blood sugar; they know their hemoglobin A1C if they're diabetic, and they often know their HDL and their LDL.  Yet, they don't know the single most important number that determines whether they're going to diet of a heart rhythm disorder," said electrophysiologist Michael Giudici, M.D., Cardiovascular Medicine, P.C. 

"If your ejection fraction is 35-40 percent or less, you're in a high risk group for Sudden Cardiac Death or Sudden Cardiac Arrest." 

A Low EF and Sudden Cardiac Arrest
Sudden Cardiac Arrest is caused by an electrical problem in the heart.  It begins as a dangerously fast heartbeat that accelerates and makes the heart an ineffective pump, unable to supply the body and brain with oxygen.  About 90-95 percent of cardiac arrest victims die before they get to the hospital. 

Without immediate treatment, Sudden Cardiac Arrest leads to Sudden Cardiac Death in minutes. 

"What we are learning is that there is a correlation between a decrease in EF and the risk of Sudden Cardiac Death or heart failure death," Dr. Foreman explained.  "We also know that a majority of people who die suddenly are people who would have said they felt pretty well."  

Sudden Cardiac Arrest often strikes without warning.   Some people may experience a racing heartbeat or they may feel dizzy, alerting them that a potentially dangerous heart rhythm has started.  But in the great majority of cases, Sudden Cardiac Arrest happens without warning. 

Sudden Cardiac Arrest is often confused with a heart attack but they are different.  Sudden Cardiac Arrest is caused by an electrical or heart rhythm problem that prevents the heart from pumping blood to the brain and organs.  A heart attack is caused by a "plumbing" problem, a blockage that prevents blood flow to the heart. 

Using tests such as an echocardiogram, doctors can see how well the heart's left ventricle works by measuring the ejection fraction, Dr. Giudici explained.  An ejection fraction of 50 percent means the ventricle pumps out half its volume each time it contracts. 

"These studies are not done routinely, so there are a lot of people out there who don't know their ejection fraction," Dr. Giudici said.  "I have many patients referred to me for low ejection fraction who are unaware of what that means."  

Heart Patients Take Notice
It's especially important to know your EF if you have: 

• Had a heart attack
• High blood pressure that isn't controlled well
• Heart valve problems
• Heart failure 
• A family link to Sudden Cardiac Arrest

Ejection fraction can be measured in many ways, but the most common is with an echocardiogram, a simple test that uses sound waves - ultrasound - to take moving pictures of the heart.  

Symptoms of a low EF may include shortness of breath, particularly during exercise, fatigue and weakness, swelling of the feet and lower legs, irregular heartbeat, abdominal discomfort and mental confusion.  But some people with low EF experience minimal, or even no symptoms. 

If your EF is too low, your physician can prescribe medications, devices, surgery or lifestyle changes. 

Throughout Genesis, a campaign is underway to make physicians and staff aware that ejection fraction is a very important number to know for heart failure patients, said Marie Williams, R.N., coordinator of cardiovascular outcomes at Genesis.  Heart failure is a key reason people 65 and older are hospitalized.  Nearly 5 million Americans have this condition, with 500,000 new cases emerging each year. 

"There are several medications that can be used for patients whose ejection fraction is lower than 35-40 percent," Williams said.  "Under a physician's supervision, following a low-sodium diet; stopping smoking; staying physically active; losing weight if you are overweight; and limiting alcohol also are important.  There are many ways to treat symptoms and to keep out of the hospital longer." 

Recognizing the early warning signs of congestive heart failure, such as fluid retention, shortness of breath and lethargy, and knowing their EF also is emphasized to heart patients undergoing Cardiac Rehabilitation, says Shari Gall, R.N., Manager of Cardiac Rehab and the Intensive Care Unit at the Genesis Illini Campus. 

Implantable Devices
Depending on the underlying cause of a low EF, an implanted device to monitor and correct abnormal heart rhythms may be recommended. 

Implantable cardioverter defibrillators (ICD's) can interrupt cardiac arrest by monitoring the heart's rhythm and delivering an electrical shock when a life-threatening arrhythmia is detected. 

"An implantable defibrillator is always on call, continuously monitoring your heart round-the-clock," Dr. Giudici said.  "It's like an emergency response team that's with you all the time." 

The interest in knowing your EF has surged over the years because new medical technology and a growing body of research has confirmed the usefulness of implantable defibrillators as primary prevention for Sudden Cardiac Arrest. 

"Back when they were first invented in the mid-80s, the food and Drug Administration recommended implantable defibrillators for patients who had had two cardiac arrests," Dr. Giudici said.   

"As we got around to the 2000s, they did a number of important studies that looked at their use for primary prevention - trying to give people car insurance before they got into a wreck rather than waiting until we already had identified a problem.  What we learned in those studies was that people who had an ejection fraction of less than 35 percent are at significant enough risk and have a better chance of being here in 5-10 years if they have an implantable defibrillator.  So now, there's a big push to identify your ejection fraction." 

• 50-75% - heart's pumping ability is NORMAL
• 36-49% - heart's pumping ability is BELOW NORMAL 
• 35% & below - heart's pumping ability is LOW

-- by Linda Barlow, Genesis