Hypoplastic Left Heart Syndrome
Condition
(HLHS)
Definition
Hypoplastic left heart syndrome (HLHS) is a rare heart problem. Structures on the left side of the heart, such as the aorta, aortic valve, left ventricle, and mitral valve, may be too small, missing, or not formed right. This reduces the amount of oxygen the body can use.
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Causes
HLHS is present at birth. It is caused by a genetic issue. It is not known why the heart does not form the right way.
Risk Factors
Things that may raise the risk of having a child with HLHS are:
- Family members who were born with heart problems
- Prior pregnancy with fetal heart problems or miscarriage
Symptoms
Within days after birth a baby may have:
- Blue/gray skin color
- Cool skin
- Problems breathing
- Sweaty, clammy skin
- Poor feeding
Diagnosis
The diagnosis may be suspected during an ultrasound before the child is born.
If the diagnosis was not made before birth, the doctor will ask about symptoms and health history. A physical exam will be done.
Pictures may be taken of the child's chest. This can be done with an echocardiogram. This can confirm the diagnosis.
Treatment
Some of these issues are hard to treat. Some options are:
- Medicines to help with blood flow
- Supportive care, such as IV fluids, a feeding tube, or help with breathing
- A series of surgeries to let the right ventricle do the work of two ventricles
Children with HLHS will need to regularly see a doctor who treats heart issues as they grow up.
Prevention
HLHS cannot be prevented.
American Heart Association
Family Doctor—American Academy of Family Physicians
CANADIAN RESOURCES:
Canadian Cardiovascular Society
Heart and Stroke Foundation of Canada
American Heart Association
Family Doctor—American Academy of Family Physicians
CANADIAN RESOURCES:
Canadian Cardiovascular Society
Heart and Stroke Foundation of Canada
References
- Feinstein, J.A., Benson, D.W., et al. Hypoplastic left heart syndrome: current considerations and expectations. J Am Coll Cardiol, 2012; 59 (1 Suppl): S1-S42. Correction can be found in J Am Coll Cardiol, 2012; 59(5): 544.
- Hypoplastic left heart syndrome. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/hypoplastic-left-heart-syndrome.
- Single ventricle defects. American Heart Association website. Available at: http://www.heart.org/en/health-topics/congenital-heart-defects/about-congenital-heart-defects/single-ventricle-defects.
Contributors
- Chelsea Skucek, MSN, BS, RNC-NIC
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