Hypoplastic Left Heart Syndrome

Hypoplastic left heart syndrome (HLHS) is a birth defect that prevents the left side of the heart from forming correctly and properly pumping oxygen-rich blood to the body. It is a type of congenital heart defect, meaning that it is present at birth. HLHS patients may have complications into adulthood, and they tend to require regular visits with a cardiologist throughout their lives. HLHS can affect the normal development of several structures on the left side of the heart, which may not be fully formed or are very small, such as the left ventricle, the mitral valve, the aortic valve, or the ascending portion of the aorta. Babies born with HLHS often have an atrial septal defect, which is a hole in the wall between the left and right upper chambers (atria) of the heart. Multiple surgeries usually are required soon after birth to bypass blood flow from the poorly functioning left side of the heart, and babies also may receive special diets to promote energy and weight gain. A heart transplant may be required in complex or severe HLHS cases.


The UAB Congenital Heart Disease Program offers the most advanced care for congenital (present at birth) heart disease, which often requires lifetime monitoring and care. Our multi-specialty team of pediatric and adult cardiologists, cardiovascular surgeons, cardiovascular anesthesiologists, and maternal-fetal medicine specialists have unique expertise in treating patients before birth and into adulthood.

UAB Medicine’s modern ultrasound equipment allows many heart defects to be diagnosed before a child is born. Screening exams performed at 18-20 weeks are recommended for expecting mothers or fathers known to have congenital heart disease. If a defect is discovered, our experts provide prenatal treatment and develop a plan for delivery and treatment after birth.

Thanks to advances in pediatric congenital care, the life expectancy for most patients now reaches far into adulthood. However, more than half of the people with congenital heart problems stop seeing a cardiologist once they turn 18. UAB’s Alabama Adult Congenital Heart Disease Program is designed to prevent that gap in care. As the only adult congenital heart disease program in the state and one of only a few in the country, our expertise greatly increases the chances that symptoms will be identified early. This helps ensure that less serious problems are addressed before they develop into larger, more life-threatening issues such as heart failure, arrhythmia, residual congenital heart defects, endocarditis, and stroke.








UAB is an active participant in research and clinical trials for the diagnosis and treatment of hypoplastic left heart syndrome. We encourage you to speak to your physician about research and clinical trial options and browse the link below for more information.

View Clinical Trials