Single Ventricle Heart Defects (SVD)

Also known as: single ventricle defect, SVD, hypoplastic left heart syndrome (HLHS), double outlet left ventricle (DOLV), tricuspid atresia and others.

What are single ventricle heart defects?

The ventricles are two of the hearts’ four chambers (the other two are called atria). The ventricles are responsible for pumping blood out of the heart.

When a baby is born with only one of the ventricles functioning  properly (or in some cases where a heart valve may be missing), this group of heart defects are called "single ventricle defects".

These include a group of quite different cardiac abnormalities.

What causes SVD?

These are rare heart defects that are present at birth. The exact cause is not known but is probably related to a genetic abnormality. Some single ventricle heart defects are often present with other congenital heart defects.

What are the symptoms of single ventricle heart defects?

The reduction in blood flow caused by single ventricle heart defects typically leads to extreme fatigue or even unresponsiveness. The baby usually has trouble breathing and feeding, and may have a blue tint to the skin or lips that indicates low oxygen levels.

Some infants will need early treatment depending on how much or how little oxygen the heart can provide.

What are SVD care options?

These are often serious heart defects that require cardiac catheterization, surgical intervention and cardiac intensive care, shortly after birth.

Nicklaus Children's hospital has the most modern facilities and expert professionals to manage these children.

Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: April 12, 2023 09:53 AM

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