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Author Spotlight: Effect of Left Atrial Ligation on Avian Embryonic Hearts and HLHS Implications
Published on: June 16, 2023
Hypoplastic Left Heart Syndrome: A Review
Diego Ramonfaur1, Xiaoya Zhang1, Abraham P Garza2
1From the Division of Postgraduate Medical Education, Harvard Medical School, Boston, MA.
Insights
Hypoplastic left heart syndrome (HLHS) is a severe congenital heart defect requiring complex surgical palliation. Improved surgical techniques have enhanced survival, but neurodevelopmental outcomes remain a critical concern.
Area of Science:
- Pediatric Cardiology
- Congenital Heart Disease
- Cardiac Surgery
Background:
- Hypoplastic left heart syndrome (HLHS) is a rare congenital heart defect characterized by an underdeveloped left ventricle.
- It invariably leads to early childhood mortality without intervention, necessitating complex palliative strategies.
Approach:
- Treatment involves a staged surgical correction, beginning with the Norwood procedure within weeks of birth.
- Subsequent procedures, including the bidirectional Glenn and Fontan operations, aim to manage systemic and pulmonary circulation.
- Novel therapeutic alternatives are being explored to enhance survival and neurodevelopmental outcomes.
Key Points:
- The prognosis for HLHS has improved due to advancements in surgical palliation.
- Survival is influenced by both modifiable and nonmodifiable factors.
- Neurodevelopmental outcomes are a significant focus for improving quality of life in HLHS survivors.
Conclusions:
- Staged surgical palliation offers a chance of survival for infants with HLHS.
- Continued research into novel treatments is crucial for improving long-term survival and neurodevelopment.
- Addressing neurodevelopmental comorbidities is essential for enhancing the quality of life for children with HLHS.
Abstract:
Hypoplastic left heart syndrome is a rare and poorly understood congenital disorder featuring a univentricular myocardium, invariably resulting in early childhood death if left untreated. The process to palliate this congenital cardiomyopathy is of high complexity and may include invasive interventions in the first week of life. The preferred treatment strategy involves a staged correction with 3 surgical procedures at different points in time. The Norwood procedure is usually performed within the first weeks of life and aims to increase systemic circulation and relieve pulmonary vascular pressure. This procedure is followed by the bidirectional Glenn and the Fontan procedures in later life, which offer to decrease stress in the ventricular chamber. The prognosis of children with this disease has greatly improved in the past decades; however, it is still largely driven by multiple modifiable and nonmodifiable variables. Novel and clever alternatives have been proposed to improve the survival and neurodevelopment of these patients, although they are not used as standard of care in all centers. The neurodevelopmental outcomes among these patients have received particular attention in the last decade in light to improve this very limiting associated comorbidity that compromises quality of life.
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