The Glenn Procedure (Hemi-Fontan)

What to expect

What happens during the Glenn Procedure?

The Hemi-Fontan or Glenn Procedure helps re-route some blood to the lungs and eases the burden on the heart’s single ventricle. More specifically, deoxygenated blood from the top part of the body is rerouted to return to the lungs instead of the heart. This procedure is performed by a skilled cardiothoracic congenitralcongenital heart surgeon with the steps as noted below:

• The Superior Vena Cava (SVC) is the vessel that brings deoxygenated blood from the top part of the body back to the heart. This vessel is disconnected from the heart and attached to the pulmonary artery (the blood vessel that provides blood to the lungs).
• The disconnection can be done in one of two ways. If performing a Glenn, the SVC is completely disconnected from the heart and sutured directly to the pulmonary artery. If performing a Hemi-Fontan, the SVC is left in place and a patch material is sutured to temporarily block the blood from flowing back into the heart and instead reroute it towards the pulmonary artery. At Riley Children’s, we typically perform the Hemi-Fontan. If the patient underwent a Norwood operation, the shunt that was placed at that surgery is disconnected.
• After this connection, deoxygenated blood from the SVC flows directly into the lungs without passing through the heart. As a result, the workload on the single ventricle heart is reduced while maintaining a reliable source of blood flow to the lungs.

Recovery

Following surgery, your baby will remain in the Cardiovascular Intensive Care Unit (CVICU) for close monitoring, including breathing support, medications to ensure comfort and support heart function and around-the-clock care.  Recovery time varies, but most babies stay in the hospital for several weeks after the operation. During this time, you will be allowed to stay close your baby in their private room equipped with a sleeping space and a private bathroom.  You may participate in rounds which are performed daily and ask any questions at any time.

What happens after recovery?

When your baby has recovered and it is almost time to go home, we may transition them to our cardiac step-down unit, where we continue to work on feeding, growth and development. We ensure that you are fully comfortable with caring for them prior to discharge. Upon leaving the hospital your child will also continue to have close follow-up in the outpatient clinic setting to ensure they are progressing well until the next procedure, the Fontan. This will include vital checks, growth monitoring as well as echocardiograms (ultrasounds) of their heart. The Fontan is the last of the three staged open-heart surgeries and is typically completed around 2-4 years of age. You will be provided with the number for our on-call staff cardiologists who are available to answer your questions 24 hours a day, 7 days a week. At Riley Children’s, your child’s recovery, ongoing care and ultimate outcome are what matter most to us.

Key points to remember

• The bi-directional Glenn or Hemi-Fontan is an open-heart surgery. It is the second surgery in a series of operations for single ventricle congenital heart defects, including Hypoplastic Left Heart Syndrome (HLHS), amongst others.
• This surgery is typically performed around the age of 6-9 months, but that timeline can be adjusted based on what is needed for your child.
• The Hemi-Fontan or Glenn Procedure helps re-route some blood to the lungs and eases the burden on the heart’s single ventricle.