By Lorenzo Benet

A mother and her 25-week-old fetus are doing well after a USC surgeon and pediatrician performed a successful in utero cardiac interventional procedure on the fetus at CHA Hollywood Presbyterian Medical Center late last month.

The minimally invasive procedure, known as a fetal aortic valvuloplasty, was a first for a Southern California hospital. Designed to treat a congenital heart defect known as critical aortic stenosis and evolving hypoplastic left heart syndrome, doctors succeeded in using a tiny balloon to open the fetus’s narrow aortic valve to increase blood flow to the body, improve left heart function and promote normal left heart growth during the critical third trimester growing stage.

“Right now mom and baby are doing well,” said obstetrician/gynecologist Ramen H. Chmait, MD, director of the USC Institute for Maternal-Fetal Health, Los Angeles Fetal Therapy at CHA Hollywood Presbyterian Medical Center, and Children’s Hospital Los Angeles (CHLA) since 2006. “We’re optimistic that the baby’s heart will be much better off because of this procedure.”

Chmait performed the procedure on Sept. 25 with Frank F. Ing, MD, Keck School professor of clinical pediatrics and CHLA pediatric interventional cardiologist. Collaborating for the first time, both physicians had previously performed the delicate fetal procedure at hospitals outside of California.

“The surgery went beautifully; we were able to open up the aortic valve,” said Ing. “Fetal cardiac intervention is a relatively new field and requires expertise, commitment and collaboration among four specialty areas: pediatric interventional cardiology, fetal echocardiography, maternal-fetal-medicine and anesthesia.”

The doctors emphasized that the partnership between the specialists from USC, Children’s Hospital, and CHA Hollywood Presbyterian was critical to the procedure’s success.

Left untreated, critical aortic stenosis results in a severely damaged left ventricle in newborn infants and can sometimes progress to a dangerous condition called hypoplastic left heart syndrome (HLHS) when the child is born. HLHS can be fatal and typically requires three separate and very risky surgeries to correct after birth.
“In fetuses with critical aortic stenosis, the aortic valve is very narrow,” said Chmait, who is also an assistant professor of clinical medicine at the Keck School. The condition “prevents normal emptying of blood from the left ventricle to the aorta. If treatment is delayed until after birth, the left ventricle can become so damaged that it cannot function normally.”

The patient was 25 weeks pregnant at the time of procedure, which took a total of three hours and involved a team of 12, including physicians and support staff. Much of that time was devoted to Chmait’s maneuvering the fetus into position by manually adjusting the mother’s abdomen. Once in place, surgeons inserted a special needle into the fetal heart’s left ventricle, inflating a tiny balloon-tipped catheter and increasing blood flow into the aorta.

Fetal aortic valvuloplasty, first performed in England in 1991, has been completed more than 100 times total in the United States. Only a handful of hospitals west of the Mississippi River have performed the procedure.