Heart disorders (acquired) - children

What is an acquired heart defect?#

Some children develop a heart problem after an illness in childhood. This is called an acquired heart defect. It is different from a congenital heart defect, which is present when a child is born.

The four main types of acquired heart disorder in children are:

• Kawasaki disease — an illness that occurs mainly in young children and may leave the heart muscle or coronary arteries damaged
• Myocarditis — inflammation of the heart muscle, which may be damaged after a viral infection, leading to poor heart function
• Cardiomyopathy — a disease of the heart muscle, caused by a genetic disorder or developing after an infection
• Rheumatic heart disease — caused by rheumatic fever, leading to heart muscle and valve damage

Kawasaki disease#

Kawasaki disease usually, but not always, affects children aged 5 years and under, and it may damage the heart muscle or coronary arteries. It is named after the Japanese pediatrician who identified it. The cause is unknown, but it is probably an abnormal reaction to a common germ. Kawasaki disease is not contagious, although it can occur in clusters.

Symptoms#

The main symptom is a persistent fever (over 38.5°C (101.3°F)) for 5 days or longer. There is usually no obvious explanation for the fever, and it generally does not respond to paracetamol. Other symptoms, usually caused by inflammation of small blood vessels (vasculitis), may include:

• A rash, sometimes in the groin region
• Red, swollen and cracked lips
• Red eyes
• A bright red, swollen tongue
• Swollen hands and feet, with a red rash on the palms and soles
• Swollen lymph nodes

Diagnosis#

There is no single test for Kawasaki disease. Diagnosis is made by excluding other possible causes of the symptoms, and may involve blood tests and an echocardiogram to examine the heart for any changes in the coronary arteries.

Treatment#

Most children who receive proper treatment make a full recovery. A few develop heart problems, including damage to the coronary arteries, and a small number need lifelong monitoring into adulthood. If no treatment is given, about 25% of patients develop inflammation of the coronary arteries (which supply blood to the heart muscle), and this can disturb the flow of blood.

The treatment is intravenous gammaglobulin (immunoglobulin), made from donated blood. Large doses usually stop the fever and other symptoms, and treatment should be given within 10 days of the fever starting to minimize heart problems. Children may also be prescribed aspirin for some weeks to help prevent coronary artery problems. However, aspirin should only be given to children on the advice of a doctor, pediatrician or cardiologist, because it is linked to Reye’s syndrome — a rare but potentially fatal disease.

Myocarditis#

Myocarditis is inflammation of the heart muscle. Infections can damage the heart’s cells. The immune system normally responds by attacking the infecting organism, but in some children this response is too aggressive and destroys heart muscle cells as well. The heart muscle can thicken and swell, and damaged cells may heal or form scar tissue. If a large part of the heart is affected, its ability to pump blood may be impaired.

In most children, myocarditis is triggered by an infection, usually viral. Possible causes include:

• Autoimmune diseases
• Influenza (flu)
• Glandular fever
• Rheumatic fever
• Rubella
• Diphtheria
• HIV

Symptoms#

There is no specific test for myocarditis, and there may be no obvious symptoms. When they do occur, symptoms can be hard to detect and may include:

• Poor circulation, showing as cold hands and feet
• Skin discoloration in blue or gray tones
• Swelling in the face, feet or legs
• Decreased urine production due to impaired kidney function
• Chest pain and palpitations
• Fever

Diagnosis#

Tests used to diagnose myocarditis may include:

• Chest x-rays, which may show whether the heart is enlarged or there is fluid in the lungs
• Electrocardiogram
• Echocardiogram (heart ultrasound)
• Blood tests to assess kidney and liver function
• Cardiac MRI
• Heart biopsy — a catheter is inserted through a leg blood vessel to obtain a tiny piece of heart muscle

Treatment#

Many children recover completely, but some develop significant heart failure. In rare cases, patients develop blood clots that lead to stroke or heart attack, or a serious heart arrhythmia that can be fatal. There is no cure; treatment focuses on the underlying cause and on supporting the heart to maintain adequate circulation. It can include:

• Bed rest and avoiding strenuous physical activity
• Medication to control blood pressure and body fluids (diuretics)
• Intravenous immunoglobulin or purified antibodies to reduce inflammation

Immunizations against the viral diseases that can trigger myocarditis, including rubella and influenza, are an important way to help prevent it.

Cardiomyopathy#

Cardiomyopathy is a disease of the heart muscle. There are three main types:

• Dilated cardiomyopathy — enlargement of one or more of the heart’s chambers
• Hypertrophic cardiomyopathy — thickening of the heart muscle
• Restrictive cardiomyopathy — the heart muscle becomes more rigid

In most cases in children, the cause is unknown. Possible factors include genetic disorders (including Noonan syndrome), heart valve problems, viral infections that trigger myocarditis, and a family history of cardiomyopathy.

Symptoms#

Some children have no symptoms in the earlier stages. When they occur, symptoms may include:

• Swelling of the hands and feet
• Swelling of the abdomen with fluid
• Breathlessness and fatigue
• Irregular heart rhythm
• Dizziness, light-headedness or fainting during physical activity

Diagnosis#

Tests may include a chest x-ray, electrocardiogram, echocardiogram, blood tests and cardiac catheterization.

Treatment#

Treatment depends on the type of cardiomyopathy and may include:

• Medications such as angiotensin-converting enzyme (ACE) inhibitors and beta blockers to improve the heart’s pumping ability
• Devices such as a pacemaker to coordinate the contractions between the left and right ventricle, or an implantable cardioverter defibrillator (ICD) to monitor the heart rhythm and deliver electrical shocks to control abnormal, rapid heartbeats
• Surgery and transplant — a heart transplant may be an option for patients with advanced symptoms or who have not responded to other measures

Rheumatic heart disease#

Rheumatic heart disease is caused by acute rheumatic fever, which is a delayed complication of a throat infection with group A streptococcus bacteria. Repeated and untreated episodes can cause long-term damage to the heart muscle or heart valves. Early diagnosis and treatment of acute rheumatic fever can prevent rheumatic heart disease.

Only a small number of people infected with the bacteria develop acute rheumatic fever, but the risk increases if the infection is not treated, usually with penicillin. Acute rheumatic fever is uncommon in many places but is more common in some populations and in lower-income settings.

Symptoms#

Symptoms of acute rheumatic fever can include:

• Fever
• Joint pain and swelling
• Carditis (inflammation of the heart)

Treatment#

Acute rheumatic fever is treated with medication, usually antibiotics including penicillin, and children with the fever are usually hospitalized. Where the disease has damaged heart valves (rheumatic heart disease), surgery may be needed to repair or replace them.

Ask your child’s cardiologist whether your child needs antibiotics for certain procedures, such as having teeth removed or other surgery involving the mouth, nose, intestinal organs or genito-urinary system. Bacteria may enter the bloodstream during these procedures and cause a serious infection (infective endocarditis) in the abnormal part of the heart. Check all medications with your pharmacist, doctor or cardiologist, and give the usual immunizations at the normal times after advice from your doctor.

Key points#

• An acquired heart defect develops after an illness in childhood, unlike a congenital defect that is present at birth.
• The four main types are Kawasaki disease, myocarditis, cardiomyopathy and rheumatic heart disease.
• Cardiomyopathy is a disease of the heart muscle, caused by a genetic disorder or developing after an infection; rheumatic heart disease follows rheumatic fever and damages heart muscle and valves.
• The cause of Kawasaki disease is unknown but is probably an abnormal reaction to a common germ; its main symptom is a persistent fever over 38.5°C (101.3°F) for 5 days or longer.
• Several of these conditions have no single diagnostic test, so diagnosis is often made by excluding other possible causes of the symptoms.

Where to get help#