Overview
Hypoplastic left heart syndrome is a rare congenital heart defect where the left side of the heart is severely underdeveloped, affecting its ability to pump blood effectively. In this condition, the left ventricle is either too small or not present, and the aortic valve and mitral valve do not function properly. As a result, blood cannot flow adequately to the body, and the right side of the heart must compensate by pumping blood to both the lungs and the rest of the body through a connection between the pulmonary artery and the aorta (ductus arteriosus). Symptoms of hypoplastic left heart syndrome include cyanosis, rapid and difficult breathing, poor feeding, cold hands and feet, weak pulse, heart rhythm problems, fluid buildup in the lungs and other parts of the body, and the need for additional heart surgery or a heart transplant. The exact cause of the condition is unknown, but having a family history of heart defects increases the risk.
Understanding the disease
Symptoms
The symptoms of hypoplastic left heart syndrome include grayish-blue color of the lips and gums (cyanosis), rapid and difficult breathing, poor feeding, cold hands and feet, weak pulse, and being unusually drowsy or inactive. In addition, if the natural connections between the heart's left and right sides close, babies can go into shock and potentially die, displaying signs such as cool, clammy skin; a weak and rapid pulse; slow and shallow or very rapid breathing; and dull eyes. If you notice these symptoms in your baby, seek medical help immediately.
Risk Factors
The exact cause of hypoplastic left heart syndrome is unknown. However, some risk factors have been identified for congenital heart defects in general, which may include:
- Rubella (German measles): Having rubella during pregnancy can cause problems in a baby's heart development. A blood test done before pregnancy can determine if you're immune to rubella. A vaccine is available for those who aren't immune.
- Diabetes: Careful control of blood sugar before and during pregnancy can reduce the risk of congenital heart defects in the baby. Diabetes that develops during pregnancy (gestational diabetes) generally doesn't increase a baby's risk of heart defects. While there are no specific risk factors mentioned for hypoplastic left heart syndrome, it's worth noting that having a family history of heart defects or having a child with a congenital heart defect could increase the likelihood of having another baby with a heart defect.
Development
In hypoplastic left heart syndrome, the left side of the heart is underdeveloped, resulting in a combination of structural and functional abnormalities. The left ventricle, which is responsible for pumping blood to the body, is either small or absent. The aortic and mitral valves on the left side of the heart do not function correctly. Additionally, the main artery leaving the heart (aorta) is smaller than usual. Due to these issues, the right side of the heart must work harder to compensate for the left side's inadequacies. It pumps blood both to the lungs and to the rest of the body through a blood vessel called the ductus arteriosus. This connection prevents the oxygen-rich blood from flowing back to the lungs, as it normally would. Despite advances in care, hypoplastic left heart syndrome remains a complex and challenging condition. It often requires medication, surgical interventions, or even heart transplantation. The causes of this congenital heart defect are not fully understood, and there is no known prevention method. If you have a family history of heart defects or have a child with a congenital heart defect, consulting with a genetic counselor and a cardiologist who specializes in congenital heart defects can be helpful.
Assessment and Diagnosis
Triage
You should seek medical help if you notice your baby has any of the symptoms of hypoplastic left heart syndrome, such as grayish-blue color of the lips and gums (cyanosis), rapid and difficult breathing, poor feeding, cold hands and feet, weak pulse, being unusually drowsy or inactive. If you think your baby is in shock, immediately call 911 or your local emergency number.
Diagnosis
Hypoplastic left heart syndrome can be diagnosed through a variety of tests, including routine ultrasound exams during pregnancy, physical examination of the baby at birth, and an echocardiogram after birth. An ultrasound can detect the condition before birth, while symptoms such as grayish-blue lips, trouble breathing, heart murmur, and abnormal heart sounds may indicate the presence of heart defects like hypoplastic left heart syndrome after birth. An echocardiogram, which uses sound waves to create images of the heart, is the most reliable method to diagnose hypoplastic left heart syndrome, revealing a small left ventricle and aorta, and any potential issues with heart valves.
Management and Treatment
Complications
Potential complications of hypoplastic left heart syndrome include:
- Heart rhythm problems (arrhythmias)
- Fluid buildup in the lungs, abdomen, legs, and feet (edema)
- Poor growth and development
- Blood clots that may lead to a pulmonary embolism or stroke These complications may occur despite proper treatment, and many babies with hypoplastic left heart syndrome can survive with appropriate care and interventions.
Home Remedies
It is important to consult with a healthcare professional who can provide personalized advice and recommendations for managing hypoplastic left heart syndrome.
Treatment
Treatment for hypoplastic left heart syndrome usually involves medication and surgery or a heart transplant. Medication: Babies born with hypoplastic left heart syndrome are often given medication to keep the ductus arteriosus open. This connection between the right and left sides of the heart helps maintain blood flow to the body until the necessary surgery can be performed. Surgery: The primary treatment for hypoplastic left heart syndrome is a series of surgeries known as the Norwood procedure, followed by the Glenn and Fontan procedures. These surgeries are performed in stages, with the first surgery typically done within the first week of life, and the subsequent surgeries occurring at around 4-6 months and 2-3 years of age. These operations are designed to reroute blood flow and improve the function of the heart. Heart Transplant: In some cases, a heart transplant may be necessary if the child's condition is severe or if they experience complications. It's important to note that advances in care have improved the outlook for babies born with hypoplastic left heart syndrome. With proper medical intervention, many affected individuals can lead healthy, active lives.
Preparing for medical consultation
To prepare for an appointment for hypoplastic left heart syndrome, you should:
- Make a list of any previous heart treatments, including medications, surgeries, or procedures you or your child have received for a heart problem.
- Be aware of any pre-appointment restrictions. When you schedule the appointment, ask if there are any forms to fill out or dietary restrictions to follow before the appointment.
- Note any symptoms, including those that may seem unrelated to hypoplastic left heart syndrome. Be specific about when they began, such as days, weeks, or months.
- Gather any relevant medical records, including echocardiogram results, and bring them to the appointment.
- Write down any questions or concerns you have for the healthcare provider. By being well-prepared, you can ensure that you make the most of your appointment and address any necessary concerns or questions effectively.