Heart Murmurs

A heart murmur is an unusual sound heard during a heartbeat, often described as a "whooshing" or "swishing" noise. It is caused by turbulent blood flow in or near the heart and can vary in loudness, pitch, and timing. While many heart murmurs are harmless, others can indicate an underlying heart condition that may require further investigation. Here’s a guide to understanding heart murmurs, their causes, symptoms, and when to seek medical attention.

What Is a Heart Murmur?

A heart murmur is essentially an extra or unusual sound heard between the normal beats of the heart. In a regular heartbeat, the heart's valves open and close smoothly, allowing blood to flow in and out without obstruction. However, a murmur occurs when there is turbulence in this flow, which can be caused by either harmless or pathological conditions. Murmurs can be detected during a physical exam with a stethoscope and are often graded on a scale from 1 to 6 based on loudness, with 1 being very faint and 6 being extremely loud.

Types of Heart Murmurs

There are two main types of heart murmurs:

Innocent (or Functional) Murmurs: Innocent murmurs are common, especially in children, and are usually harmless. They are often due to temporary or benign changes in blood flow, such as increased blood flow during pregnancy or childhood growth. Innocent murmurs typically don’t require treatment and don’t indicate heart disease.

Abnormal (or Pathologic) Murmurs: Abnormal murmurs are more likely to be caused by an underlying heart problem. They may be due to congenital heart defects, valve abnormalities, or acquired conditions. These murmurs often require further testing and medical intervention, depending on the severity and the underlying cause.

Causes of Heart Murmurs

The cause of a heart murmur depends on whether it is innocent or abnormal.

Innocent Murmur Causes

Innocent murmurs often occur when blood flows more rapidly than usual through the heart. Common triggers include:

Physical activity or exercise: Increased blood flow during exercise can create benign murmurs.

Fever: Higher body temperature increases the heart rate, causing more rapid blood flow.

Pregnancy: During pregnancy, the body circulates more blood to support the growing fetus.

Anemia: Low red blood cell levels can lead to increased blood flow and a functional murmur.

Abnormal Murmur Causes

Abnormal heart murmurs are typically linked to structural issues with the heart, often involving heart valves or congenital heart defects. Common causes include:

Heart Valve Issues: Damaged or improperly functioning valves are a leading cause of abnormal murmurs.

Stenosis: A condition where a valve is narrowed, restricting blood flow.

Regurgitation (or Insufficiency): This occurs when a valve does not close completely, allowing blood to flow backward.

Congenital Heart Defects: These are structural problems in the heart present from birth, such as septal defects (holes between the chambers of the heart), which allow blood to flow abnormally.

Endocarditis: This is an infection of the inner lining of the heart, typically involving the valves, and can lead to abnormal murmurs if the infection damages the heart tissue.

Rheumatic Fever: This condition, which can follow untreated strep throat, can damage heart valves and lead to murmur-causing abnormalities.

Symptoms of Heart Murmurs

Many heart murmurs are asymptomatic, especially if they are innocent. However, in cases where a heart murmur is related to a structural issue, additional symptoms might be present. Symptoms associated with abnormal heart murmurs can include:

Shortness of Breath: Difficulty breathing, especially during physical activity, can indicate restricted blood flow.

Chest Pain: Pain or discomfort in the chest may signal a heart-related issue.

Fatigue: Unexplained tiredness or inability to exercise without getting overly exhausted can be a sign of heart strain.

Cyanosis: A bluish tint on the lips, skin, or fingertips due to insufficient oxygen in the blood, often seen in babies with congenital heart conditions.

Dizziness or Fainting: Reduced blood flow or low oxygen levels may cause lightheadedness or fainting.

Swelling: Swelling in the legs, feet, or abdomen can indicate heart failure related to valve issues or other heart diseases.

Diagnosing Heart Murmurs

When a murmur is detected, a healthcare provider will likely perform additional tests to determine its cause and severity. Diagnostic tests may include:

Echocardiogram: This is an ultrasound of the heart, which provides detailed images of its structure and function. An echocardiogram can reveal issues with the heart valves, heart chambers, and blood flow.

Electrocardiogram (ECG or EKG): This test records the electrical activity of the heart, helping to identify arrhythmias or other heart issues that may be related to murmurs.

Chest X-ray: A chest X-ray can show the size and shape of the heart, revealing any structural abnormalities that may contribute to a murmur.

Cardiac Catheterization: In this procedure, a thin tube is inserted into the heart through a blood vessel to measure pressures and blood flow. It is generally used when other tests indicate a more serious problem.

Blood Tests: These can identify underlying conditions like anemia or infection, which may contribute to or result from heart problems.

Treatment for Heart Murmurs

Treatment for a heart murmur depends on its cause and severity. Innocent murmurs usually require no treatment and may resolve on their own. However, abnormal murmurs related to heart disease or structural issues may require one or more of the following treatments:

Medications: Certain medications can help manage symptoms and treat underlying conditions that cause abnormal murmurs.

Antibiotics: In cases of endocarditis, antibiotics can treat the infection.

Blood Pressure Medication: For valve issues or other heart problems, blood pressure medications can reduce strain on the heart.

Anticoagulants: These help prevent blood clots, which can occur when blood flow is abnormal.

Valve Repair or Replacement: For severe valve-related murmurs, surgery may be required to repair or replace a faulty valve, restoring normal blood flow.

Septal Repair: In cases of septal defects, surgical procedures can close the holes in the heart, improving circulation and oxygenation.

Lifestyle Adjustments: For some individuals, lifestyle changes such as regular exercise, a heart-healthy diet, avoiding smoking, and managing stress can support heart health and reduce symptoms associated with murmurs.

When to Seek Help

If you or a loved one is experiencing symptoms of a heart murmur, it’s essential to consult a healthcare provider to determine whether the murmur is innocent or abnormal. Seek medical attention if you experience any of the following:

Shortness of breath, especially when at rest or during mild exertion

Chest pain, tightness, or pressure

Unexplained fatigue or weakness

Swelling in the legs, feet, or abdomen

Fainting or lightheadedness

Rapid or irregular heartbeat

Prompt evaluation by a healthcare provider is critical, as untreated heart conditions can lead to serious complications, including heart failure, arrhythmias, or stroke.

Living with a Heart Murmur

For many people, having a heart murmur does not significantly impact daily life, especially if it’s an innocent murmur. However, those with abnormal murmurs related to heart disease may need ongoing care, regular check-ups, and possibly lifestyle adjustments to manage their heart health.

Educating yourself on the potential symptoms and risks associated with abnormal murmurs can help you make informed decisions about when to seek help and how to maintain heart health. With proper medical guidance and, if necessary, treatment, most people with heart murmurs can lead healthy, active lives.