Large hole in boy's liver repaired using innovative catheterization procedure

Through an innovative catheterization procedure, a pediatric cardiologist at Texas Children's Heart Center in Houston repaired a severe liver condition in a 14-year-old male.

The doctor used a catheter and septal occluder device that is generally used to close holes in children's hearts. Similar procedures have been reported only six times in medical literature. But this is the first time the procedure has been performed with this particular device.

"Sammy was born with a hole in his liver about the size of a garden hose that has caused him complicated health problems," said Dr. Henri Justino, an interventional cardiologist at Texas Children's Heart Center and an assistant professor of pediatrics at Baylor College of Medicine. "Since we successfully perform a wide variety of interventional cardiac procedures in the catheterization lab every day, we consulted with colleagues in the Liver Center, and decided to apply the same procedure in Sammy's case," said Justino.

Sammy Drake, a resident of West Texas, was born with a rare liver problem known as patent ductus venosus (PDV). The ductus venosus, a large vein that crosses through the liver and empties near the heart, is normally present before birth and plays an important role in the development of the fetus. After birth, however, the PDV is no longer needed and usually closes on its own. Closure of this vein allows blood returning from the intestines to go to the liver, an essential step needed to filter certain nutrients and toxins in foods.

In Drake's case, the PDV did not close. Instead, it allowed blood returning from the intestines carrying toxic ammonia, to take a shortcut through the PDV directly into the heart and lungs. The high concentration of ammonia in Sammy's bloodstream was toxic to many organs, including his brain. Ammonia likely contributed to his chronic lung problems, making him so short of breath that it is difficult for him to speak.

Justino performed the unusual catheterization procedure by inserting two long straw-like catheters into the liver through veins in Sammy leg and neck. Once the catheters reached the liver, the doctor was able to locate and measure the size of the PDV by injecting a dye while viewing through an x-ray camera. Justino then deployed a mesh-like occluder device through one of the catheters, thus filling the liver's large abnormal vein. The new device now blocks the shortcut channel through the liver. Soon, tissue will grow around the mesh and make a complete closure.

"This is an excellent example of cooperation across medical services," says Dr. Saul Karpen, director, Texas Children's Liver Center and associate professor of pediatrics at Baylor College of Medicine. "Sammy's ultrasound of the liver looks spectacular, and his now-normal ammonia levels are the lowest they have ever been in his life. Without the procedure to close the PDV, Sammy would possibly require a liver transplant or risk progressive brain damage from the toxic ammonia," Karpen said.