Maia's Heart

At birth, the two major congenital heart defects Maia has been diagnosed with are Double Outlet Right Ventricle (DORV) and Hypoplastic Left Heart Syndrome (HLHS). Aside from these, she also has other CHDs, including a hole in her heart between the ventricles called a Ventricular Septal Defect (VSD), and Coarctation (narrowing) of the Aorta. The causes are unknown and treatment/surgery will depend on the anatomy of her heart at birth. Since Maia has a hypoplastic left ventricle, the doctors decided the best thing to do is the 3-stage surgery that will eventually convert her heart into a single ventricle heart. 

Children's Hospital of Philadelphia - Hypoplastic Left Heart Syndrome 
Center for Disease Control - Congenital Heart Defects 

Children's Hospital of Philadelphia - Double Outlet Right Ventricle
National Library of Medicine/National Institute of Health - Double Outlet Right Ventricle

Children's Hospital of Philadelphia - Coarctation of the Aorta
National Library of Medicine/National Institute of Health - Coarctation of the Aorta

Surgical repair of Hypoplastic Left Heart Syndrome (HLHS)
(Congenital Heart Institute of Texas website)

The surgical options for HLHS include cardiac transplantation and the Norwood Procedure. The Norwood Procedure is the first of a series of operations designed to have the blue (unoxygenated) blood flow directly to the lungs and then use the existing right heart to pump the red (oxygenated) blood to the body. All three stages are done through a median sternotomy (chest) incision.

Stage I - Norwood Procedure/Sano Modification ProcedureThe Sano Modification of the Norwood involves the placement of a conduit (light blue tube below) between the pulmonary artery and the right ventricle instead of the Modified Blalock-Taussig Shunt.
The Sano shunt modification avoids the problem of competitive flow between the lungs and coronary arteries. The shunt is constructed from a slightly larger Gortex tube graft than that used for the modified Blalock shunt. Generally a 5 mm tube graft is selected in contrast to the 3.5 mm graft used for averagesize babies for a Blalock shunt. Distally, the graft is connected to the main pulmonary artery between the right and left pulmonary artery takeoffs. The proximal end of the shunt is connected to a limited infundibular incision in the right ventricle.

Stage II - Bidirectional Glenn Shunt: The blue blood from the head, neck and upper body is directed to the right lung artery through the superior vena cava. This allows the blood to flow into the lungs for oxygen. The temporary shunt from the Stage I operation is removed. The Stage II procedure reduces the work load of the heart.

Stage III - Extracardiac Fontan Procedure: The blue blood from the lower part of the body is directed to the lungs. This is done using the inferior vena cava and artificial material (Gortex(r) ). A conduit (tube) is fashioned from the material. It is connected from the inferior vena cava to the pulmonary artery. This bypass or rerouting allows the blue blood to enter the lungs without being pumped by the heart. The heart remains available to receive the red blood from the lungs and then pump it to the body. Sometimes, a small hole (fenestration) is placed in the baffle (with a snare around it) to allow the heart and body to adjust gradually to the new blood flow system. The single hole is closed later via a small incision. (Another method is to place several small holes in the baffle to allow the heart and body to adjust gradually to the new blood flow system. These holes close off on their own a few months after surgery.)

Goals of the procedure:
  • separate the red and blue blood
  • have the blue blood enter the lungs directly
  • have the heart itself as the pump of oxygen-rich blood to the body

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