Physician listening to a heart beatShare on Pinterest
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The aortic valve allows blood to leave the heart and travel through the aorta, which is the largest artery in the body. Aortic stenosis is when this heart valve narrows and doesn’t open fully.

The sound of blood moving through the narrowed valve is called aortic stenosis murmur. A healthcare professional can often detect it by listening to your heart with a stethoscope. The murmur has a high pitch.

Aortic stenosis murmur is one of a few different types of heart murmurs. It can sometimes be the first clue that heart valve disease is present and that a more in-depth medical evaluation is necessary.

In mild cases of aortic stenosis, regular monitoring may be all that’s necessary. For more severe cases, aortic valve repair or replacement may be needed.

The sound of blood flow through the heart’s four valves is usually described as “lub-dub”:

  • The “lub” sound is the beginning of the heart’s contraction (systole) as the mitral and tricuspid valves close and the aortic and pulmonary valves open.
  • The “dub” sound represents the closure of the aortic and pulmonary valves and the opening of the other two valves.

Aortic stenosis prevents healthy blood flow out of the left ventricle into the aorta, which supplies blood to most of the body. When healthy blood flow is disrupted by a problem with one or more heart valves, a different sound emerges.

These changes are called heart murmurs. They may be slight and difficult to detect or very obvious and accompanied by other symptoms of valve disease.

Grading system for heart murmur intensity

Heart murmurs are sometimes characterized as “whooshing” or “swishing” sounds. Doctors grade them from 1 to 6 based on loudness or intensity:

  • Grade 1: faint murmur, barely audible
  • Grade 2: soft murmur
  • Grade 3: easily audible but without a palpable thrill
  • Grade 4: easily audible murmur with a palpable thrill
  • Grade 5: loud murmur, audible with stethoscope lightly touching the chest
  • Grade 6: loudest murmur, audible with stethoscope not touching the chest

Most murmurs will increase or decrease in volume when you perform certain maneuvers. Doctors use this dynamic quality of murmurs as a clinical tool during physical exams to help diagnose a specific murmur.

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Most heart murmurs can be categorized into a few different types:

  • Systolic: the murmur can be detected when the heart is contracting (systole)
  • Diastolic: happens when the heart is resting (diastole)
  • Continuous: the murmur occurs when the heart is pumping or at rest

An aortic stenosis murmur is a systolic murmur because it occurs as blood is trying to move through the constricted opening of the stiffened aortic valve.

You may have symptoms of aortic stenosis separate from the murmur. However, symptoms don’t usually occur until blood flow is significantly restricted.

When symptoms do develop, they can include:

  • chest pain
  • difficulty exercising, including walking or climbing stairs
  • dizziness or lightheadedness
  • racing or fluttering heart
  • shortness of breath
  • trouble sleeping
  • fainting

Aortic valve stenosis can affect anyone, but it’s more common in older adults, often from calcium buildup in the valve flaps or leaflets.

When aortic stenosis is diagnosed in young people, it’s usually because they were born with a faulty aortic valve. In these cases, the person was born with a valve that has two leaflets instead of three leaflets in the aortic valve.

Aortic stenosis murmur makes a high-pitched sound. The point at which it occurs during systole often reveals the severity of the valve problem.

Researchers in a 2021 article noted that aortic stenosis murmur is often illustrated in a diamond shape, with a crescendo at the widest part of the diamond and the decrescendo at the diamond’s narrowest points.

If the crescendo occurs early in systole, the stenosis tends to be mild. As the valve disease worsens, the crescendo moves to a later portion of systole. This is because it takes longer for the left ventricle to pump as much blood as it can through the narrow valve, and the valve closure is usually delayed, too.

When a doctor or other healthcare professional listens to your heart with a stethoscope, the process is called auscultation. One of the key things they’re listening for is the “lub-dub” sound or any possible variation that could indicate heart trouble.

Other tests can indicate the presence of aortic stenosis and the disruption of robust blood flow through the aortic valve. One of the main screening tools is an echocardiogram. This test uses sound waves to create moving images of an organ on a computer monitor.

A special kind of echocardiogram called a transesophageal echocardiogram (TEE) uses a thin, flexible ultrasound probe that’s lowered through the esophagus near the heart so it can provide even more detailed images of the aortic valve.

Sometimes, a doctor may order the following tests to confirm or rule out an aortic stenosis diagnosis:

  • cardiac CT scan
  • cardiac MRI
  • chest X-ray
  • electrocardiogram
  • exercise stress test

Aortic stenosis murmur is only a symptom. This means effective treatment of aortic stenosis should eliminate the murmur and other symptoms.

The three primary treatment options include monitoring, repair, and replacement.

1. Monitoring

When there are no other noticeable symptoms and blood flow through the heart is adequate, a doctor may recommend regular monitoring of your heart function. They may also recommend monitoring the valve for disease progression. This is done with an echocardiogram.

2. Repair

Aortic valve repair may involve open heart surgery or a catheter procedure.

In a catheter procedure, a doctor threads a catheter up through an artery to the aortic valve in the heart. Once there, a deflated balloon at the catheter’s tip is inflated, widening the narrowed valve.

This approach is called balloon valvuloplasty. It’s an option if there hasn’t yet been significant damage to the aortic valve.

3. Replacement

When valve repair isn’t possible, a doctor may recommend the entire valve gets replaced.

Open heart surgery can replace the diseased valve with a cow or pig valve, or with a mechanical valve or bioprosthetic valve.

A nonsurgical option called transcatheter aortic valve replacement (TAVR) can be done using a catheter to guide a new valve up to the heart, where it’s placed over the diseased valve.

According to 2016 research, aortic valve replacement, rather than repair, is recommended when symptoms become noticeable.

Aortic stenosis murmur is a high-pitched sound that can be heard when a healthcare professional listens to your heart with a stethoscope. The sound means there’s a disturbance in the usual steady flow of blood throughout the heart.

The murmur occurs because the aortic valve is narrowed and stiff, and cannot completely open to allow healthy blood flow out of the left ventricle and into the aorta. In many cases, the sound of aortic stenosis murmur is the first sign of aortic valve stenosis.

In mild cases, aortic stenosis may have no significant symptoms other than a barely detectable murmur. In severe cases, aortic stenosis often calls for a repair or replacement of the stenotic valve.