Heart murmur

Heart murmur . Murmurs are sounds created by blood to the circular cavities or valves the heart or through the blood vessels near the heart.


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  • 1 Introduction
  • 2 Main causes of heart murmurs
  • 3 Main types of murmurs
  • 4 Symptoms
  • 5 Diagnosis
  • 6 Treatments
    • 1 Modification of lifestyle
    • 2 Medications
    • 3 Surgical procedures
  • 7 Heart murmur in children
  • 8 Diagnosis in children
  • 9 Do all murmurs involve heart disease?
  • 10 Functional Puff
  • 11 Congenital heart disease
    • 1 Most frequent heart diseases
  • 12 Sources


Normal heart sounds are produced in pairs. They are often described as a constant “lab-dab, lab-dab.” The first “lab-dab” is the sound the mitral and tricuspid valves make when closing. The second “lab-dab” is the sound made by the aortic and pulmonary valves closing immediately afterward. But if there is a problem, other than this normal lab-dab, a murmur may occur. By listening to the heart with a stethoscope, the doctor can determine if the abnormal sound indicates turbulence. This is called a heart murmur.

Some heart murmurs are of a harmless type called “functional murmur” or “innocent murmur.” They are common in children and require no treatment or lifestyle changes. In most cases, functional murmurs disappear when they reach adulthood.

Although some heart murmurs are functional, others are symptoms of a more serious heart problem. In these cases, the sound could indicate that blood is flowing through a heart valve that is damaged or straining, that there may be a hole in one of the walls of the heart, or that there is a narrowing in one of the blood vessels in the heart. heart.

Main causes of heart murmurs

Heart murmurs can be caused by various factors or diseases, including the following:
Defective heart valves. When blood must pass through a narrowed valve (called stenosis), or when it leaks back through a faulty valve (called regurgitation). These valve problems can be congenital (from birth) or occur later due to rheumatic fever, coronary artery disease, infective endocarditis, or the aging process.

Holes in the walls of the heart (atrial septum defect or ventricular septum defect)
Reconstructive surgery for congenital heart defects (present at birth).
Processes such as pregnancy, anemia (decreased red blood cells), high blood pressure, fever, or an overactive thyroid gland can also cause an intermittent heart murmur.

Main types of murmurs

The doctor will evaluate a murmur based on various factors. The murmurs are analyzed to know the tone, volume and duration. They are also classified according to their intensity (on a scale of one to six, where one is the weakest and six is ​​the strongest).

Types of murmurs include the following:

  • Systolicmurmur – a heart murmurthat occurs during a contraction of the heart muscle. Systolic murmurs are divided into ejection murmurs (due to blood flowing through a narrowed vessel or irregular valve) and regurgitation murmurs.
  • Diastolicmurmur – heart murmur that occurs during relaxation of the heart muscle between beats. Diastolic murmurs are caused by a narrowing (stenosis) of the mitral or tricuspid valves or regurgitation of the aortic or pulmonary valves.
  • Continuousheart murmur – heart murmur that occurs throughout the cardiac cycle.

Murmurs related to congenital heart disease (present at birth) or another problem involving the structures of the heart will be heard louder in the area of ​​the chest where the problem occurs. Some major defects have almost no murmur in the newborn due to the normally high pressures in the blood vessels of the lungs. The murmurs can be inconsistent and difficult to hear in a baby who is agitated or crying. In this way, the murmurs can be overlooked or undetected.


Most people who have heart murmurs have no symptoms. Murmurs are usually discovered during a medical examination due to other symptoms, such as chest pain, shortness of breath, tiredness, or the presence of a bluish discoloration of the skin or fingertips (called “cyanosis”). »).


In most cases, the doctor will be able to hear the heart murmur using a stethoscope to listen to the heart (a technique called “cardiac auscultation”). Heart murmurs change according to body position or breathing, so the patient may be seen standing, squatting, and lying down and asked to take a deep breath or hold their breath while the doctor listens to the heart.

To determine if the murmur is functional or if it is due to another heart problem, the doctor may also order the following studies:

  • A chest x-ray to determine if the heart is enlarged.
  • An electrocardiogram (ECG) to determine if there is any irregular heartbeat (arrhythmia) or if the heart is enlarged.
  • An echocardiogram to examine the function of the valve, the movement of the heart wall, and the size of the heart.
  • A study with a special medicine called “amyl nitrate” that is used to define certain heart murmurs. The doctor will ask you to inhale the medicine, which momentarily alters blood pressure and heart rate.


Treatment of the heart murmur depends on the cause. Functional heart murmurs generally do not need any treatment. If the heart murmur is due to an underlying disease, such as high blood pressure, that disease is treated. If the heart murmur is due to valve disease itself (intrinsic valve disease) or other heart defects, you may need to take medicine or perform a surgical procedure.

Modification of lifestyle

Doctors used to prescribe antibiotics to their heart murmur patients before a dental or surgical procedure to prevent infection of the heart valves. (Some of these procedures may cause bacteria to enter the blood stream, which can lead to infection.) Today, most doctors believe that patients with a heart murmur do not need antibiotics before a dental procedure or Surgical, unless the murmur is caused by an intrinsic valve disease. If you don’t know if you should take antibiotics before a procedure, talk to your doctor or dentist.


The doctor may prescribe certain medications, depending on the underlying cause of the heart murmur.

  • Blood thinners (anticoagulants), which can prevent blood clots from forming that can clog blood vessels.
  • Beta-blockers, which help normalize rapid heartbeat and flutter.
  • Medicines that reduce blood pressure (antihypertensive), which relieve stress on the heart.
  • Antiarrhythmics, which control heartbeat irregularities (arrhythmia) and relieve symptoms of heart palpitations.
  • Diuretics, which reduce blood pressure by removing excess fluid and salt from the body.
  • Digoxin, which strengthens the heartbeat.

Surgical procedures

In some patients, surgery may be necessary to correct a heart defect or to correct or replace a damaged heart valve.

Heart murmur in children

Although many parents fear the worst when their child is diagnosed with a heart murmur, it is important to know that this diagnosis is actually extremely common. In fact, many children get a heart murmur at some point in their lives. Most murmurs should not be a cause for concern and have no impact on the child’s health.
So what exactly is a heart murmur? In itself, the term heart murmur is neither a diagnosis nor a disease; But, to understand what it means, it is important to know how the heart works.

The heart is divided into four chambers; two on the left side and two on the right. Blood from the body is pumped to the lungs, where it is oxygenated, and then pumped through the arteries to the rest of the body. Once oxygen is used, the blood returns to the heart through the veins and is pumped back to the lungs to re-oxygenate.
The word murmur describes a hissing sound that blood makes when it flows through any of the heart’s chambers or valves or even through a hole inside the heart.

Diagnosis in children

The murmur is heard when the child is heard with a stethoscope. Since a child’s heart is very close to the chest wall, subtle sounds can be heard more easily. However, it may sometimes happen that the pediatrician cannot hear a murmur unless the child sits up and is very still. Although they can be heard in very young babies, murmurs are most often detected when children are 2 to 4 years old. Some pediatricians believe this is because most children have had time to become familiar with and confident about their pediatrician, making them quieter and more cooperative during the examination.

Heart murmurs are rated on a scale of 1 to 6. The 1st degree is barely audible, while the 6th? it sounds very loud. Your child’s pediatrician will also look at what part of the heart the murmur is in, what type of noise it makes (for example, if it looks more like a touch or a blow), when in the heart cycle it occurs, and if modifies when the child changes position. When your child’s pediatrician discovers the murmur, he or she may refer the child to a pediatric cardiologist, if he or she feels the evaluation needs to be completed.
Because of the widespread misconception that heart murmurs are serious, it is important for parents to understand what type of murmur their child has and if they need further evaluation.

Do all murmurs involve heart disease?

Not all murmurs are symptoms of heart disease. Sometimes a murmur can be heard in a normal child who has a fever or is anemic; These murmurs disappear when the underlying problem is treated.

Some children have what is known as an innocent breath. These murmurs are not related to congenital heart disease and usually resolve when the child reaches adulthood. If your child’s doctor hears an innocent murmur, they may want to carry out additional tests to make sure there is no heart disease. The child who has an innocent murmur can lead a normal life and be as active as any healthy child.

Functional Puff

The most common type of heart murmur is the so-called functional or harmless. This diagnosis implies that the murmur is produced by a normal and completely healthy heart. It can appear and disappear throughout childhood. It usually disappears by itself as the child grows and does not pose any risk to health.

Children who have functional murmurs do not need to follow a special diet, restrict their activities, or any other special treatment. Children who are old enough to understand that they have a murmur must be assured that they are no different than other children and that they can lead completely normal lives.

Congenital heart disease

Some heart murmurs may indicate that there is a problem with the heart. If your child’s pediatrician suspects that the child may have something more important than a functional murmur, he or she will refer you to a pediatric cardiologist, who may send you or do additional tests such as a chest x-ray, an ECG (electrocardiogram), or an echocardiogram. An echocardiogram, or “echo,” allows a special moving picture to be made of the heart chambers and of how blood flows through the heart. Records the size and shape of the heart’s chambers, valves, and blood vessels. It also shows the direction of blood flow through the heart and helps determine how efficiently this organ is pumping.

About 1 in 100 babies is born with a structural heart problem, called congenital heart disease. These babies may have symptoms of heart disease as early as the first few days of life, or they may appear to be completely healthy until much later. Some children will have no symptoms other than a heart murmur, but others will have symptoms that could be mistaken for other diseases or disorders.

Symptoms of major heart disease in a newborn include:

  • Fast breathing
  • Difficulty feeding
  • Bluish or purple lips (called cyanosis)
  • Delayed growth.
  • Symptoms in a child or adolescent may include:
  • Fatigue
  • Difficulty exercising or practicing physical activities
  • Chest pain

If you notice any of these symptoms in your child, contact your pediatrician.

Congenital heart defects are caused by genetic factors (including chromosomal abnormalities such as Down syndrome or DiGeorge syndrome, a rare congenital disease of genetic origin) and by environmental factors (such as exposure to chemicals for industrial use), but many children do not have any known risk factors. Some parents may have more than one child with a heart condition, but in most cases, heart disease is not considered inherited.

The mother’s health during pregnancy also plays a role. Women who are more likely to give birth to a child with heart disease are those who during pregnancy:

  • They contract rubella
  • Have untreated or uncontrolled diabetes
  • They have phenylketonuria (a metabolic disorder of genetic origin).
  • Some medications can also increase the chances of having a child with congenital heart disease. Drinking alcohol during pregnancy or the fact that the mother or father uses drugs are also risk factors.
  • Babies who have other types of abnormalities or who are born prematurely may also have heart disease.

More frequent heart diseases

The most common heart problems in children are structural abnormalities, which can cause a heart murmur and include the presence of holes inside the heart (interatrial communication or ventricular septal defect), and valve abnormalities (aortic valve stenosis or pulmonary).

Abnormalities in the heart septum affect the walls that divide the heart into 4 chambers. When there is a hole in the heart septum, blood can flow through it to the other heart chambers. This excess blood can cause a murmur. It can also cause the heart to overwork and consequently increase in size. Some holes may be large enough to produce symptoms other than the murmur; others are smaller and sometimes end up closing on their own over time.

Valve abnormalities are also frequent. Between the heart chambers there are 4 valves (one-way openings) that prevent the blood from backing up when it is pumped. When a valve narrows or becomes blocked, it does not allow blood to flow freely; Valves with abnormal morphology may not be effective in preventing blood from flowing back into the heart. In either of these cases, there will be a murmur.

If your child has any of these heart conditions, it may be mild enough that it does not require any treatment. A pediatric cardiologist will help you decide whether the abnormality needs to be treated, and if so, whether surgery is required or some other procedure is best.


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