Heart Murmur

What causes a heart murmur?

A murmur is caused by turbulent or abnormal blood flow across your heart valves.

If blood is flowing more rapidly than normal, it can cause an innocent heart murmur (also called normal or physiologic). This type of murmur is common during:

• Childhood.
• Exercise.
• Growth spurts.
• Pregnancy.
• The first few days after a baby is born.

Innocent heart murmurs can disappear and reappear. They may get louder when your heart beats faster. They often go away eventually, but some last a lifetime. Innocent heart murmurs don’t indicate a problem with your heart.

Some heart murmurs are due to a heart problem or other condition, including:

• Anemia: or low red blood cell count, can cause a murmur because it affects blood viscosity (thickness). Other signs of anemia include weakness and fatigue (extreme tiredness).
• Carcinoid syndrome or carcinoid heart disease is a slow-growing tumor (cancer) caused by extra hormones, which can affect your heart. A person with carcinoid syndrome might also experience unexplained weight loss, belly pain, diarrhea or low blood pressure.
• Congenital heart defect: Your heart may have a structural problem that’s been there since birth. Examples of congenital heart defects include a septal defect (hole in your heart) or tetralogy of Fallot.
• Endocarditis is a heart infection. Bacteria or other germs get into the bloodstream and attack your heart valves. It usually causes additional symptoms, like fever, chills, rash or sore throat.
• Heart valve disease means one or more heart valves aren’t working correctly, preventing good blood circulation. For example, a valve may be stiff (valve stenosis). It may not open or close all the way. Or it may allow blood to leak in the wrong direction (valve regurgitation). Other signs include swelling in your ankles or feet, heart palpitations (fluttering), shortness of breath or pressure in your chest.
• Hyperthyroidism, also called overactive thyroid, the gland makes too much thyroid hormone. The condition also may cause anxiety, increased appetite, rapid heartbeat and weight loss.
• Hypertrophic cardiomyopathy is a type of heart disease that makes your heart muscle larger, thicker or stiffer. It can be inherited or develop due to aging or high blood pressure. Other symptoms may include syncope (fainting), chest pain, heart palpitations, fatigue and shortness of breath.

How is a heart murmur diagnosed?

A healthcare provider can diagnose a heart murmur by listening to your heart. A murmur makes an abnormal swishing sound.

Your provider listens to your heart with a stethoscope from different places on your chest and back. They listen for certain things in your heartbeat:

• Lub-dub sound instead of swishing.
• Pitch.
• Rhythm.
• Timing.
• Volume.

Your healthcare provider may ask you to do different things while they listen:

• Grip your hands.
• Sit.
• Squat.
• Stand suddenly.
• Lie down.

What tests might I have if a healthcare provider hears a heart murmur?

If a healthcare provider hears a murmur, you may need further testing to rule out a health problem. You may be referred to a cardiologist, a physician who specializes in the heart.

Tests that can determine the cause of a heart murmur are:

• Chest X-ray: A chest X-ray takes pictures inside your chest to find any structural problems.
• Echocardiogram: Echocardiogram (also called an echo) uses sound waves to create images of your heart’s valves and chambers. It helps examine your heart’s pumping action. This can be a surface ultrasound or a more specialized ultrasound procedure through your mouth and esophagus, which gives better pictures than the surface ultrasound.
• Electrocardiogram: Electrocardiogram(also called an ECG or EKG) is a painless test that measures the electrical activity of your heart.

What is the outlook for people with a heart murmur?

The outlook for people with a heart murmur depends on the condition causing it. Kids often outgrow childhood murmurs, and a murmur with pregnancy usually goes away after childbirth. However, murmurs associated with heart conditions require medical treatment.

How can I prevent heart murmurs?

Heart murmurs can’t be prevented. But you can avoid serious problems from a heart condition by getting your heart checked regularly.