10 Things to Know About Heart Murmurs

by Amanda Loudin Health Writer

You’ve just received a heart murmur diagnosis, which can sound pretty scary. But don’t panic—many heart murmurs aren’t dangerous. The heart is a pump comprised of four valves, and murmurs occur when blood flows in or near the heart and a type of turbulence occurs. (In hearts without murmurs, blood flows smoothly and quietly.) Some heart murmurs, known as “innocent” murmurs, are exactly that: harmless. Others, however, may indicate a more serious problem, like heart valve disease (HVD) or a congenital heart defect (meaning, it’s present at birth). Here, we’ll explain how to know the difference.

pregnant couple

Some Murmurs Are Benign, Others a Concern

“Anyone can have a murmur,” says Sandra Lewis, M.D., a cardiologist at Legacy Health System in Portland, OR. “During pregnancy the volume of blood increases, and this might cause a murmur. Or, an athlete whose blood is pumping strongly may have [one],” she adds. About 10% of adults and 30% of children have innocent murmurs, but others are problematic, including endocarditis, a valve infection. “Bacteria can damage a valve and lead to a murmur,” says Dr. Lewis. “Sometimes this can be treated, but often a damaged valve needs to be replaced.”

close father and son

Aging and Genetics Linked to Heart Murmurs

Other origins of heart murmurs and HVD include calcification in the aortic valve as people age. “Calcium leaves our bones and moves into the wrong places as we get older,” says Dr. Lewis. “A calcified valve may need to be replaced, even in our 80s and 90s.” A heart attack can also damage a valve, while other valve issues may be genetic. For instance, about 1% to 2% of the population is born with only two cusps in their aorta, instead of three. This can limit or cause abnormal blood flow, requiring surgical treatment.

A hand holding a newborn baby's foot.

Birth Defects Can Cause Murmurs

Heart murmurs can be present at birth. “Pediatricians will listen to a baby’s heart to check for a murmur,” explains Brent Muhlestein, M.D., interventional cardiologist at Intermountain Healthcare Institute in Salt Lake City, UT. If one is detected, the baby may be given an echocardiogram to look for structural abnormalities in the heart. In utero, babies have a very different circulation—sometimes congenital heart defects are only discovered after birth, which may, on occasion, require immediate surgery. Other times, pediatricians take a wait-and-see approach.

chest pain

Murmurs May Signal Heart Valve Disease

When a murmur indicates HVD, it can present with a variety of symptoms—or sometimes with no indicators, because HVD can progress slowly, according to the American Heart Association. People with symptoms may experience chest pain or palpitations, shortness of breath, fatigue, weakness, light-headedness, and even fainting. Even if symptoms seem minor, the condition can be serious, leading to an enlarged heart and even failure, so it’s important to mention to your doctor anything that seems “off." With endocarditis, symptoms can include fever, night sweats, and/or weight loss.


Different HVD Types Trigger Murmurs

If your heart murmur is the product of valve disease, what’s going on? In some cases, it can be valve stenosis, which means the valve is narrow, tight, and stiff. This limits the forward flow of blood. Or, you could be experiencing valve regurgitation, which means a valve isn’t closing completely, allowing backward blood flow. This is commonly known as a “leaky” valve. In either case, this disturbance in blood flow is what causes the abnormal sound, or murmur. In rare instances, a heart attack can lead to cell death in the heart muscle, which can cause an acute-onset murmur.


Listening and Ultrasound Help Diagnose Murmurs

A diagnosis of a heart murmur and/or HVD usually begins with the doctor simply listening to your heart. “A physical exam is not enough, however, if a murmur is detected,” says Dr. Muhlestein. “The next step is an echocardiogram to try to determine the cause.” A standard tool, an echocardiogram is a special type of ultrasound that will help doctors see the valves and heart muscle, along with blood flow. At this point, a cardiologist is usually involved in the diagnosis, but if not, your treating physician will refer you to one.

surgical equipment

Treatment Depends on Type

Treatment for heart murmurs will vary and depend on the type and resulting condition. The seriousness of murmurs from HVD exist on a wide gradient and so, too, will treatment. In the case of children born with a congenital condition, physicians may monitor them as they grow. In other cases, treatment of infection with medication, valve replacement surgery, or procedures to close holes may be in order. “In congenital heart disease, structural repairs may be complex, requiring lifelong observation and intervention,” says Dr. Lewis.


A Healthy Lifestyle Can Help

While anyone can develop a heart murmur or HVD, certain activities can increase your risk, as does aging. Genetics can also play a role. “You want to follow the same good habits as you would for overall heart health,” says Dr. Muhlestein. “No smoking, a healthy diet, regular exercise, avoiding drugs, and keeping alcohol intake moderate.” High blood pressure, hyperthyroidism, and infection can also contribute to a murmur or HVD. Family history may indicate a higher likelihood of a murmur, as well. Remember that many murmurs are completely innocuous but for those that aren’t, living well can make a difference.

eating with friends

Living a Normal Life With a Murmur

Living with a heart murmur can look different from one person to the next. For those diagnosed as innocent, no lifestyle changes are required. If you’ve gone through surgery or other treatment, however, following your doctor’s orders and maintaining healthy life habits is essential. “Follow up on a regular basis if your valve was replaced,” says Dr. Muhlestein, “because sometimes they wear out.” The good news is that no matter what the cause and/or treatment of your murmur or HVD, in most cases, a healthy, normal life can be expected.

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Amanda Loudin