According to the American Heart Association, approximately 5.7 million adults in the United States have heart failure—a condition that occurs when the heart muscle becomes weak or stiff and can no longer pump blood as effectively as it should. While almost everyone over the age of 65 has some degree of heart failure, there are many ways heart health can be improved. And one of the most promising might just be amino acids. In this article, we’re going to discuss amino acids for heart failure and uncover the many benefits they may offer for people struggling with the effects of this serious medical condition.
What Causes Heart Failure?
Heart failure can be caused by a variety of disorders, but the most common culprit is coronary artery disease—a type of heart disease in which cholesterol and other substances form plaques on the walls of arteries, causing them to become hard and narrow.
According to the Centers for Disease Control and Prevention (CDC), coronary artery disease kills over 370,000 people in the United States each year. However, a number of other conditions can also lead to the development of heart failure. These include:
|High blood pressure||Myocardial infarction|
|Insulin resistance and diabetes||Drug and alcohol abuse|
While many use the terms heart failure and congestive heart failure interchangeably, congestive heart failure actually refers to a specific type of heart failure in which the heart’s ability to pump blood becomes so compromised that it can no longer coordinate blood flow out of the heart with blood returning via the veins.
Heart Failure: Types and Symptoms
The heart is composed of four chambers—two upper chambers called the atria and two lower chambers called the ventricles. Heart failure generally begins on the left side of the heart, specifically in the left ventricle—the largest and most muscular of the heart’s four chambers.
The cardiac dysfunction that characterizes left-sided heart failure can be further subdivided into systolic and diastolic heart failure. With systolic heart failure, the left ventricle becomes enlarged, which weakens it and decreases its ability to contract normally. This type of heart failure is accompanied by a reduction in ejection fraction—a measure of the percentage of blood being pumped out of the heart with each beat.
By contrast, people with diastolic heart failure maintain a normal ejection fraction because the issue with the left ventricle is not its ability to contract, but rather its ability to relax after a contraction. With this type of heart failure, the left ventricle is unable to fill properly.
Symptoms of left-sided heart failure may include:
- Shortness of breath
- Fluid retention
- Rapid heartbeat
- Reduced exercise capacity
- Persistent cough
Heart failure can also affect the right side of the heart, usually as a consequence of left-sided failure and the added burden that places on the right side. However, right-sided failure can also be the result of lung disease, pulmonary hypertension, or damage from a heart attack.
People with right-sided heart failure experience symptoms similar to those seen with left-sided failure. However, the severity of right-sided heart failure symptoms is generally greater than that seen with left-sided failure.
Heart Failure Risk Factors
There are many factors that put a person at risk of developing heart failure. Some of these include:
- Certain medications
- Sleep apnea
- Viral infections
- Tobacco use
Even though heart failure can lead to life-threatening cardiovascular events, symptoms can often be improved with appropriate treatment and lifestyle choices, including healthy diet and body weight, exercise, and stress management.
But there’s also more and more evidence to indicate that amino acids could play a crucial role in the treatment and prevention of heart failure as well.
Making the Case for Amino Acids for Heart Failure
Most of us probably think our muscles do nothing but hold us upright and enable us to move about. However, the reality is that our muscles play an important role in a number of body processes, including regulating glucose levels and increasing lifespan.
Moreover, studies have shown that people with heart disease are much more likely to have a positive outcome if they maintain muscle mass and strength.
And this is where amino acids come in.
Protein is necessary for almost every biological process, and as the building blocks of protein, amino acid concentrations must be high enough to allow protein synthesis to occur. As long as plenty of amino acids are available, our bodies are supported in their efforts to see to the business of building and maintaining muscle—including heart muscle.
In addition, essential amino acid supplements have been shown to help stave off cachexia (body wasting) by improving both muscle strength and function.
We know that essential amino acids may help offset hypercatabolic, or excessively destructive metabolic, states like chronic heart failure. We also know that amino acid supplies are limited in heart failure patients, which leads to abnormalities in heart and skeletal muscle metabolism and eventual loss of heart function and quality of life.
A number of recent studies have also demonstrated the potential benefits of amino acid supplementation in heart failure.
For example, a recent study published in the journal Nutrients investigated the hypothesis that consumption of a specially formulated composition of essential amino acids can stimulate the net gain of body protein in individuals with heart failure to a greater extent than a commercially popular protein-based dietary supplement (designed to support individuals with heart failure with greater caloric but lower essential amino acid content).
Participants in the study had an average age of around 80 years and were classified as obese, with an average body mass index (BMI) of approximately 33.
The essential amino acid–based formulation consisted of the amino acids histidine (1.6%), isoleucine (9.6%), leucine (34%), lysine (13.6%), methionine (2.7%), phenylalanine (5.5%), threonine (6.8%), valine (6.8%), tryptophan (2.7%), and citrulline (10.9%) and contained 48 kilocalories per serving.
By contrast, the protein-based nutritional supplement (Ensure Active Heart Health chocolate drink, Abbott Nutrition, 237 milliliters) consisted of 8 grams of protein in the form of milk protein isolate and soy protein isolate as well as approximately 21 grams of carbohydrates and 3 grams of fat, for a total of 140 kilocalories per serving.
Interestingly, the net gain in body protein (determined by stable isotope tracer methodology) for participants given the essential amino acid formulation was found to be more than twice that seen in those receiving their protein intake from the Ensure dietary supplement.
What’s more, the anabolic (muscle-building) response to the essential amino acids was found to be even greater when the amount of calories consumed was taken into account—a significant finding for a population that tends to be overweight or obese.
These findings led researchers to conclude that an essential amino acid formulation designed specifically to promote protein synthesis in individuals with heart failure is superior to a protein-based dietary supplement.
These results are also consistent with a 2010 study published in the Mediterranean Journal of Nutrition and Metabolism. This study was designed to determine whether an essential amino acid supplement improved quality of life, cardiac function, and exercise tolerance in 27 male patients with stable chronic heart failure.
Participants were given thyroxine (T4), vitamins B1 and B6, and an essential amino acid–based supplement twice a day for 3 months. The dietary supplement used in this study contained the amino acids leucine, lysine, isoleucine, valine, threonine, cysteine, histidine, phenylalanine, methionine, and tryptophan.
After 3 months on this regimen, a significant improvement was found in all three parameters tested, indicating that essential amino acid supplementation can be useful for improving cardiac function, quality of life, and exercise tolerance in patients with stable chronic heart failure.
A separate clinical trial published in 2014 in Clinical Medical Insights: Cardiology investigated the effects of amino acid supplementation in 13 male patients with stable chronic heart failure. Like the aforementioned study, this study was conducted over 3 months.
Researchers measured exercise tolerance with a cardiopulmonary stress test and a 6-minute walking test and evaluated quality of life with the Minnesota Living with Heart Failure Questionnaire.
Similar to the 2010 study, this study found that amino acid supplementation was well tolerated and helpful in improving exercise tolerance. (However, unlike the previous study, participants reported no improvement in quality of life.)
In addition, a study from 2018 found that supplementation with the branched-chain amino acid (BCAA) leucine was able to prevent rat heart failure after administration of the chemotherapy drug doxorubicin. This is an important finding in light of the known risk of heart failure with the use of chemotherapy medications.
It’s also important to note that leucine was the most abundant amino acid used in the studies described above.
Beyond helping to maintain muscle in heart failure patients, amino acids can also help regulate blood flow and improve energy metabolism.
Two amino acids, in particular, that can be used to target impaired blood flow are citrulline and L-arginine, both of which have been shown to increase the production of nitric oxide, which acts as a vasodilator and helps regulate muscle blood flow.
In addition, the essential amino acid and BCAA leucine is known to stimulate the production of new mitochondria—the organelles where energy is produced. And the amino acid carnitine can improve the transport of fatty acids into the mitochondria, which helps these organelles function more efficiently.
Likewise, an increasing body of evidence suggests that the amino acid taurine may be effective in reducing the risk of cardiac dysfunction and heart failure, as well as reducing oxidative stress.
As you can see, amino acid supplements show promise as a safe and natural way to help improve the symptoms of both heart failure and many of the cardiovascular diseases that can contribute to the development of a failing heart.
However, it’s important to remember that amino acids for heart failure work best when used as part of a balanced formulation that includes all nine essential amino acids.