Jugular Vein Distention (JVD): Causes and Treatments
What Does Ejection Fraction Have To Do With Heart Failure?
By Steven Schiff, MD, as told to Stephanie Booth
My patients' concerns about heart failure are usually, "What is my prognosis?" "What are the treatments, like medication and surgery, that are available to me?" But some people will ask me for their ejection fraction (EF) number if they've read about it, or had it discussed with them. This is especially true if they want to know if it's changing over time.
What is EF?
EF is one of many measurements of how well your heart works. It measures the active pump function of your heart when it contracts and pumps blood out of your heart and into your arteries.
Technically, EF is the percentage (fraction) of blood that is ejected from your heart as it contracts. (This is also known as the stroke volume).
Mathematically, EF is the amount of blood pumped with each beat, divided by the amount of blood in the chamber when it's filled.
Your heart has two phases for each heartbeat:
Therefore, EF is the stroke [contracted] volume/diastolic volume.
What does EF have to do with heart failure?
A low ejection fraction lets a doctor know that the active pumping phase of the heart isn't working. It's usually tied to some, but not all, types of heart failure.
Heart failure with a low EF is called "systolic" heart failure.
How is EF measured?
EF is usually measured, with an echocardiogram or cardiac ultrasound. It can also be measured during a heart angiogram and catheterization. That's when catheters (tubes) are put inside of you through an artery, into your heart chambers.
Other measurement techniques include:
All of these techniques are estimates, and can show slightly different results in the same person.
What do EF numbers mean?
Normal EF is in the range of 55% to 70%. As the percentage falls, it tells the doctor that the heart failure is getting worse. In general, if the EF falls below 30%, it's relatively severe. A reading of 20% or below is very severe heart failure.
It's important to know that there's not always a perfect correlation between symptoms and the EF. In addition, an EF above 75% is considered too high, and can be a problem as well.
How can your EF help manage your heart health?
Your EF can be a way of assessing the status and progression of heart failure over time, as well as a way to track the benefits of various heart failure treatments.
For instance, you may be told your EF, then start on medication or go for surgery, and may want to know: "Did my EF go up or down?" We can track serial measurements of EF (usually by echocardiogram) to see if your treatment is helping.
How can you have normal EF and heart failure?
Heart failure with a normal EF is happening more and more often. It's generally related to the filling phase of the heart's cycle of filling and emptying. It is called "diastolic heart failure."
Normal hearts are very compliant. This means that they fill easily, at relatively low pressures. Sometimes, even though the heart contracts normally (normal EF), it might need higher pressure to fill for each beat.
If so, you can have symptoms of heart failure even though your heart contracts normally, with a normal EF. You could have fluid accumulation and overload. We see this most frequently in people with untreated high blood pressure.
Should you find out your EF?
Most people without cardiac issues don't need to know their EF.
If you're simply worried about this, ask your doctor if you should be concerned. A simple echocardiogram will provide a good estimate.
The most important thing to know, if you have been told of heart failure, is what the underlying cause is. That will affect your prognosis, treatment, testing and follow-up.
Among the most common causes [of heart failure] are:
Once you've been given a heart failure diagnosis, you should be seen by a cardiologist for a careful review of your underlying causes, the status of your heart failure, your current treatment, follow up, and prognosis.
Initial EGFR Dip Does Not Worsen Outcomes In Dapagliflozin Initiators With HFpEF
The initial decline in estimated glomerular filtration rate (eGFR) after starting dapagliflozin does not lead to adverse cardiovascular or kidney outcomes in patients with heart failure who have mildly reduced (HFmrEF) or preserved ejection fraction (HFpEF), investigators report.
In a prespecified secondary analysis of the DELIVER randomized clinical trial (ClinicalTrials.Gov, NCT03619213), an initial eGFR decline exceeding 10% was not significantly associated with adverse cardiovascular or kidney composite outcomes in patients treated with 10 mg dapagliflozin daily, Finnian R. McCausland, MBBCh, MMSc, of Brigham and Women's Hospital in Boston, Massachusetts, and colleagues reported in JAMA Cardiology. Placebo recipients with that level of eGFR decline, however, had a significant 33% increased risk of the cardiovascular composite outcome, which included cardiovascular death or a heart failure event compared with nondippers. Placebo recipients with an initial eGFR dip also had higher risks than nondippers of the kidney composite outcome, which included a 50% or more eGFR decline, eGFR less than 15 mL/min/1.73m2 or end-stage kidney disease, or death from kidney causes.
Results were similar when initial eGFR decline was analyzed as a continuous measure.
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These data will be informative to clinicians and patients and, with appropriate monitoring, should provide reassurance for continuation of these medications in the majority of patients.
The median eGFR dipped significantly lower in the first month in the dapagliflozin than placebo group: -4 vs -1 mL/min/1.73m2. The dapagliflozin group had significant 1.9-fold increased odds of an initial eGFR dip of more than 10% within the first month of drug initiation compared with the placebo group.
Despite an initial eGFR dip, trial data show sodium glucose cotransporter 2 inhibitors slow long-term kidney function decline compared with placebo, Dr Causland's team pointed out. The chronic eGFR slope after 4 months appeared similar among dippers and nondippers receiving dapagliflozin in this study.
These results in HFpEF and HFmrEF are in line with findings on dapagliflozin initiation in patients with chronic kidney disease. In patients with heart failure with reduced ejection fraction, an initial eGFR dip after dapagliflozin initiation was significantly associated with a 27% lower risk of the primary cardiovascular outcome.
"These data will be informative to clinicians and patients and, with appropriate monitoring, should provide reassurance for continuation of these medications in the majority of patients," Dr Causland's team wrote.
Disclosure: The DELIVER trial was sponsored by AstraZeneca. Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors' disclosures.
This article originally appeared on Renal and Urology News
What Is Heart Failure With Preserved Ejection Fraction? Your FAQs Answered
Heart failure with preserved ejection fraction (HFpEF) occurs when the heart doesn't relax adequately. This is also known as diastolic heart failure.
Heart failure occurs when your heart doesn't pump enough blood to meet your body's needs or when the heart doesn't relax enough and pressures inside the chambers can rise. This can cause fatigue, breathing difficulties, and fluid buildup in your tissues.
According to the Centers for Disease Control and Prevention (CDC), an estimated 6.2 million U.S. Adults have heart failure. Roughly half of those people have HFpEF.
Read on to learn about HFpEF and get the answers to common questions about treatments, outlook, and more.
Heart failure with preserved ejection fraction (HFpEF) is a type of heart failure that occurs when the muscle in the left ventricle stiffens and is less able to relax, so the pressure inside the heart rises.
HFpEF is usually caused by:
To understand HFpEF, it helps to know how your heart works. Your heart is composed of four chambers:
The right atrium receives oxygen-depleted blood from the rest of your body and sends it to your right ventricle, which pumps the blood to your lungs to pick up oxygen.
The left atrium receives oxygen-rich blood from your lungs and sends it to your left ventricle, which pumps the blood to the rest of your body.
The movement of blood depends on the rhythmic relaxation and contraction of your heart chambers. This is known as the cardiac cycle.
In the cardiac cycle, there is a diastole and systole phase.
Your heart chambers (called ventricles) relax during the diastole phase of the cardiac cycle, which allows the heart chambers to fill with blood. Your heart muscle contracts during the systole phase, which pumps the blood.
If you have HFpEF, your left ventricle becomes stiff and can't relax properly. This prevents it from filling with enough blood during the cardiac cycle's diastole phase.
The filling occurs with higher pressure, which reduces the amount of blood available to pump throughout the body during the systole phase. This causes a backup of fluid into the lungs and the body.
As a result, less oxygen-rich blood is delivered to your organs and other tissues. Because of its high pressures, HFpEF can also cause fluid to build up in your tissues, which is known as congestive heart failure.
Heart failure with reduced ejection fraction (HFrEF) is also known as systolic heart failure. It also affects the left ventricle but in different ways.
In HFrEF, the left ventricle is too weak rather than too stiff. It cannot contract properly.
It may fill with enough blood during the cardiac cycle's diastole phase, but it can't pump that blood with enough force during the systole phase, so the amount of blood ejected (ejection fraction) is reduced.
Ejection fraction is a measurement that compares the amount of blood that fills your ventricle to the amount of blood that your ventricle pumps out with each contraction.
A typical ejection fraction is 55–70%. If your ejection fraction is below 50%, you may have HFrEF.
If you have HFpEF, you may actually have a typical ejection fraction. That's because there's less blood coming into the stiffened left ventricle, but your heart can still pump that blood back out of the ventricle.
Though the proportion of blood going in and the proportion going out is typical, your body still isn't getting enough oxygenated blood with each cardiac cycle.
Your doctor won't be able to tell whether you have HFpEF and HFrEF based on your symptoms alone.
To measure ejection fraction and diagnose the type of heart failure you have, your doctor may order tests such as:
Your doctor may prescribe diuretics to limit fluid buildup in your tissues.
They may also prescribe treatments to manage other chronic health conditions or cardiovascular risk factors you may have.
For example, they may prescribe medication to:
Your doctor may encourage you to make other lifestyle changes if necessary, including to:
Scientists are studying other treatments for HFpEF. The Food and Drug Administration (FDA) approved the drug combination sacubitril and valsartan (Entresto) in February 2021 for people with HFpEF.
Your doctor can help you learn about new treatment options as they become available or advise you if you qualify for a clinical trial testing new drugs for HFpEF.
Heart failure is a potentially life threatening condition.
A 2017 study found that all people hospitalized with heart failure survived for a median of 2.1 years. Roughly 75% of people hospitalized with HFpEF in this study passed away within 5 years.
Cardiovascular and heart failure readmission rates were higher in those with HFrEF than those with HFpEF.
Some people live for longer with HFpEF. Your outlook depends on:
Many people with HFpEF have other health conditions and cardiovascular risk factors, such as:
These conditions and risk factors raise the risk of poor health outcomes.
Getting treatment for HFpEF and other chronic conditions may help improve your quality of life and outlook. Practicing healthy habits is also important.
Roughly half of people with heart failure have HFpEF.
This condition reduces the amount of oxygen-rich blood that your heart delivers to other tissues and organs and increases the pressure in your heart.
It can cause uncomfortable symptoms and raise your chances of developing potentially life threatening complications.
It's important to get treatment for HFpEF and other chronic health conditions you may have. Your doctor may prescribe medications and other treatments. They may also encourage you to change your lifestyle to protect your heart and overall health.
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