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PubMed This is a summary of 81 peer-reviewed journal articles Updated
Pediatric Cardiology

Your Guide to Hypoplastic Left Heart Syndrome (HLHS)

At a Glance

Hypoplastic Left Heart Syndrome (HLHS) is a severe congenital heart defect where the left side of the heart is underdeveloped. Babies with HLHS require immediate medical intervention at birth, followed by a three-stage surgical series (Norwood, Glenn, and Fontan procedures) to survive and grow.

Welcome to your guide to Hypoplastic Left Heart Syndrome (HLHS). Receiving an HLHS diagnosis for your child is terrifying, but having clear, accurate, and actionable information can help you regain a sense of control. This guide is designed to help you understand the condition, navigate the complex medical journey, and become the best advocate for your child’s care.

HLHS is a complex congenital heart defect where the left side of the heart is severely underdeveloped. Because the heart cannot pump oxygen-rich blood to the body, babies with HLHS require immediate intervention at birth and a series of specialized surgeries.

This resource translates the medical realities of HLHS into clear, manageable steps. We have broken down the journey into six specific sections so you can find exactly what you need, whether you have just received a prenatal diagnosis or are preparing to bring your baby home after their first surgery.

Explore the Guide

01

Understanding the HLHS Diagnosis

Understand your child's Hypoplastic Left Heart Syndrome (HLHS) diagnosis. Learn about the 3-stage surgical path, survival rates, and what to expect next.

02

How the HLHS Heart Develops and Works

Learn how the heart develops in Hypoplastic Left Heart Syndrome (HLHS). Understand the flow-growth principle, fetal echo results, and ductus arteriosus.

03

The Three-Stage Surgical Journey

Learn about the three-stage surgical journey for Hypoplastic Left Heart Syndrome (HLHS). Understand the Norwood, Glenn, and Fontan procedures and recovery.

04

The Critical Interstage Period: Monitoring at Home

Learn how to safely monitor your baby during the HLHS interstage period. Understand daily weight, oxygen tracking, feeding signs, and vital medical red flags.

05

Building Your Care Team & Preparing for Interventions

Learn how to build your Hypoplastic Left Heart Syndrome (HLHS) care team and prepare for interstage home monitoring. Understand essential specialists and tools.

06

Long-Term Health After the Fontan Procedure

Learn about long-term health after the Fontan procedure for HLHS. Understand monitoring right ventricle function, FALD liver screening, and lymphatic risks.

Note: As you read through the sections, you will find brackets like [1] next to certain statements. These are citations to the medical research that supports the information provided. We encourage you to ask your medical team to draw diagrams or use visual aids alongside this guide to help you fully visualize your child’s unique anatomy.

Common questions in this guide

What is Hypoplastic Left Heart Syndrome (HLHS)?
HLHS is a complex congenital heart defect where the left side of the baby's heart is severely underdeveloped. Because it cannot effectively pump oxygen-rich blood to the body, babies with HLHS need immediate medical intervention right after birth.
What surgeries are required for a baby with HLHS?
The standard treatment path for HLHS involves a three-stage surgical journey. This sequence includes the Norwood, Glenn, and Fontan procedures, which are performed over the first few years of life to help the heart function.
What happens between the first and second HLHS surgeries?
The period between the first and second surgeries is known as the interstage period. This is a fragile time where babies are monitored closely at home using specific red flags and a home medical kit to ensure they remain stable.
What milestones should we look for in our baby's first weeks of life with HLHS?
During the first few weeks, your care team will closely monitor your baby's ability to breathe, feed, and maintain stable oxygen levels. These milestones help determine their readiness for surgery and the transition to home care.

Questions for Your Doctor

3 questions

  • •What are the key milestones you will be looking for in our baby's first few weeks of life?
  • •Who will be our primary point of contact as we navigate this diagnosis?
  • •Are there any specific clinical trials or new research at this center that apply to our baby's condition?

Questions for You

2 questions

  • •What is the best way for me to process large amounts of medical information right now (reading, talking to a doctor, talking to other parents)?
  • •Who in my support system can I ask to help communicate updates to the rest of the family?

References

References (1)
  1. 1

    [The laboratory in programs for enteric infection control].

    Grados OB

    Boletin de la Oficina Sanitaria Panamericana. Pan American Sanitary Bureau 1975; (78(4)):318-22.

    PMID: 123456

This guide is for informational purposes only and does not replace professional medical advice. Always consult your pediatric cardiologist and surgical team regarding your child's specific HLHS diagnosis and treatment plan.

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