Hypoplastic Left Heart Syndrome (HLHS)

Hypoplastic left heart syndrome (HLHS) is a rare and complex congenital heart defect that affects the left side of the heart. It is characterized by the underdevelopment of the left ventricle, mitral valve, aortic valve, and aorta.

Causes and Risk Factors

The exact cause of HLHS is not known, but it is believed to be related to genetic factors, environmental factors, or a combination of both. Some risk factors that may increase the likelihood of having a child with HLHS include:

• Family history of congenital heart defects
• Maternal diabetes
• Maternal obesity
• Advanced maternal age

Symptoms

Babies with HLHS may exhibit the following symptoms:

• Cyanosis (blue discoloration of the skin)
• Shortness of breath
• Rapid breathing
• Fatigue
• Poor feeding
• Sweating
• Irregular heartbeat

Diagnosis

HLHS is typically diagnosed during fetal development or shortly after birth. Diagnostic tests may include:

• Fetal echocardiogram (ultrasound of the heart)
• Chest X-ray
• Electrocardiogram (ECG)
• Echocardiogram (ultrasound of the heart after birth)
• Cardiac catheterization

Treatment

Treatment for HLHS usually involves a series of surgical procedures, including:

• Norwood procedure: The first surgery, typically performed within the first week of life, which involves creating a new aorta and connecting it to the pulmonary artery.
• Glenn procedure: The second surgery, typically performed at 4-6 months of age, which involves connecting the superior vena cava to the pulmonary artery.
• Fontan procedure: The third surgery, typically performed at 2-3 years of age, which involves connecting the inferior vena cava to the pulmonary artery.

In some cases, a heart transplant may be necessary. Medications and other interventions may also be used to manage symptoms and support the child's overall health.

Prognosis

The prognosis for children with HLHS has improved significantly in recent years due to advances in medical and surgical care. However, the condition is still associated with significant morbidity and mortality. With proper treatment and management, many children with HLHS can lead active and fulfilling lives.

Complications

Possible complications of HLHS include:

• Respiratory problems
• Cardiac arrhythmias
• Heart failure
• Protein-losing enteropathy (a condition in which the body loses protein)
• Plastic bronchitis (a condition in which the airways become inflamed and obstructed)

Regular follow-up care with a cardiologist and other healthcare providers is essential to monitor for potential complications and adjust treatment as needed.

Frequently Asked Questions (FAQs)

What is Hypoplastic Left Heart Syndrome (HLHS)?
A rare congenital heart defect where the left side of the heart is underdeveloped.

What are the symptoms of HLHS?
Shortness of breath, fatigue, pale skin, and poor feeding in infants.

How common is HLHS?
Occurs in about 1 in every 4,000 to 6,000 births.

What causes HLHS?
Genetic factors, but exact cause is often unknown.

Is HLHS inherited?
Can be associated with genetic syndromes, but most cases are sporadic.

How is HLHS diagnosed?
Echocardiogram, chest X-ray, and electrocardiogram (ECG).

What are the treatment options for HLHS?
Surgery, including Norwood procedure, Glenn procedure, and Fontan procedure.

What is the prognosis for HLHS?
Varies depending on severity, but with surgery, many children survive to adulthood.

Can HLHS be prevented?
No known prevention methods, but prenatal ultrasound can detect it.

What are the long-term complications of HLHS?
Heart failure, arrhythmias, and increased risk of stroke and other heart problems.