What is Hypoplastic Left Heart Syndrome?

Cardiology | by Dr. Ashok B Malpani | Published on 04/11/2024

The heart is one of the vital organs of the human body and is in charge of pumping blood throughout the body. But what if some part of this important organ could not develop? 

Hypoplastic Left Heart Syndrome (HLHS) is a rare congenital condition that affects newborn babies. In this condition, the left side of a baby’s heart is not developed completely, which affects its ability to pump blood effectively. 

The left side of the heart consists of several parts—the left ventricle, mitral valve, aortic valve, and ascending aorta. In HLHS, these parts are either missing or too small to function adequately, which affects blood flow and can lead to severe symptoms early in life.

Since the left side of the heart is crucial for sending oxygen-rich blood to the body, babies born with HLHS need immediate and ongoing medical attention. If you or your family are facing any issues related to heart health, you can book an appointment with one of the best cardiologists in Kolkata at BM Birla Heart Research Hospital to ensure a proper diagnosis and effective treatment based on the patient's symptoms.

Signs and Symptoms of Hypoplastic Left Heart Syndrome

HLHS symptoms often appear within the first few days of a baby’s life since the baby’s body starts to struggle with low oxygen levels.

• Cyanosis - a condition that makes the colour of skin blue or greyish due to insufficient oxygen. 
• Difficulty in breathing or rapid breathing
• Poor feeding or difficulty gaining weight
• Weak pulse and cool extremities

Such symptoms occur due to insufficient oxygen supply by the heart to the body. A prompt medical evaluation is required to confirm and treat the condition. 

Causes of HLHS

• The exact cause of HLHS has not been established, although some factors may have contributed to it. 
• Some of these risk factors include genetic mutations, family history of congenital heart disease, and some environmental factors during pregnancy.
• Medical science is yet to discover why these heart structures fail to fully develop, with ongoing investigations focusing on understanding the genetic aspect of the disease and whether there is a role of the environment as well.

Who is at risk of HLHS?

• Hypoplastic Left Heart Syndrome (HLHS) occurs more commonly in males, though the exact reason for this is not entirely understood. 
• Research suggests there may be genetic factors at play, and families with a history of congenital heart defects may have a slightly increased risk. 
• While HLHS is not typically inherited in a direct pattern, certain genetic syndromes associated with heart abnormalities, like Turner syndrome, may increase the chances.
• The survival rates for HLHS after the series of surgeries (Norwood, Glenn, and Fontan) have improved notably in recent years. The survival rates can reach approximately 70-75% by the five-year mark after the complete surgical series, though this can vary based on individual factors. 

Hypoplastic Left Heart SyndromeTreatment

Managing HLHS is not easy and involves a multi-stage process. These procedures aim to improve flow and oxygen delivery in the body. Through a series of surgical interventions, the flow of blood in the body is rerouted to make up for the poor development of the left side of the heart.

The following are the main surgical stages:

Sometimes, if the interventions are not enough or if complications arise, then a health professional may consider a heart transplantation. However, it comes with its own challenges, including lifelong immunosuppressive medication to prevent rejection and the limited availability of donor hearts.

Where there is hope, there is a way!

When you welcome a new life, your first prayer is for their health and happiness. HLHS can be stressful for any family. Though it is a serious concern that needs immediate attention, it can be improved with the right assessment, quick medical intervention, and advanced treatments.

Our team of healthcare professionals at BMB, Kolkata, combines expertise, technology, and compassion to offer each child a chance to grow and live a meaningful life. We are committed to providing the best possible care for children suffering from HLHS and other congenital heart conditions. 

FAQs 

Is HLHS genetic?

While HLHS is not strictly hereditary, genetic factors are believed to play a role in its development. A family history of congenital heart defects may increase the likelihood, but no specific gene directly causes HLHS. Suggestion: Genetic counselling may be helpful for families with a history of congenital heart disease to assess risks in future pregnancies.

What is the life expectancy for babies with HLHS?

It is usually determined by factors such as the success of surgeries and the person's overall health condition. Although children diagnosed with HLHS can reach adulthood, there may be some complications that require timely medical interventions. 

Can HLHS be detected before birth?

Yes, HLHS can often be diagnosed during a prenatal ultrasound. If suspected, a follow-up by a foetal echocardiogram offers a detailed examination of the baby’s heart.