Deanna M. Neff, MPH
Hypoplastic left heart syndrome is a rare heart defect. In a normal heart, the blood flows in from the body to the right atrium. It then goes into the right ventricle. Next, the blood travels to the lungs through the pulmonary valve. Here, it picks up fresh oxygen. The blood returns to the left atrium and goes into the left ventricle. The blood then moves out to the rest of the body.
With this syndrome, structures on the left side of the heart, which includes the aorta, aortic valve, left ventricle, and mitral valve, may be:
Since the heart cannot function properly, oxygen-rich blood flow to the body is limited. This condition requires immediate care from a doctor.
Hypoplastic left heart syndrome is present at birth. It is not known exactly why the heart does not develop normally.
Factors that may increase your chance of having a child with hypoplastic left heart syndrome include:
Symptoms usually appear within days after birth. Tell the doctor if you notice the following in your infant or child:
You will be asked about your child's symptoms and medical history. A physical exam will be done.
Images may be taken of your child's chest. This can be done with:
Electrocardiogram (EKG) can monitor the heart's electrical activity.
Talk with your doctor about the best treatment plan for your child. Some defects may be so severe that they are difficult to treat. Treatment options include:
Medications are necessary to keep blood flowing through the ductus arteriosus. The ductus arteriosus is a connection between the pulmonary artery and the aorta, which is the largest artery in the body. It usually closes within a few days after birth. Keeping this passage open is a temporary treatment. Other medications may be used as well.
Surgery may be done to improve blood flow. This can be done through a variety of reconstructive and shunting procedures. Surgeries are usually done in stages:
Your child will need to see a heart specialist regularly. Heart medication will be needed throughout your child's life.
There are no current guidelines to prevent hypoplastic left heart syndrome because the cause is unknown. Getting proper prenatal care is always important.
American Heart Association
Family Doctor—American Academy of Family Physicians
Canadian Cardiovascular Society
Heart and Stroke Foundation of Canada
Hypoplastic left heart syndrome. EBSCO DynaMed website. Available at:
http://www.ebscohost.com/dynamed. Updated January 25, 2016. Accessed June 6, 2016.
Hypoplastic left heart syndrome. Johns Hopkins Children's Center website. Available at:
http://www.hopkinschildrens.org/Hypoplastic-Left-Heart-Syndrome.aspx. Updated May 16, 2011. Accessed June 6, 2016.
Single ventricle defects. American Heart Association website. Available at:
http://www.heart.org/HEARTORG/Conditions/CongenitalHeartDefects/AboutCongenitalHeartDefects/Single-Ventricle-Defects_UCM_307037_Article.jsp. Updated October 21, 2015. Accessed June 6, 2016.
Last reviewed June 2016 by Kari Kassir, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
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