Imagine a baby who weighs less than two pounds. Now imagine that baby has a life-threatening, congenital heart condition called patent ductus arteriosus (PDA), in which the opening between the two blood vessels leading from the heart hasn’t closed. Now imagine performing open-chest surgery on that tiny neonate.
“Patent ductus arteriosus is a significant problem for many premature babies,” pediatric cardiologist William S. McMahon, MD, said. Usually, however, it closes on its own. That’s not the case in micropreemies, defined as babies born before the 26th week of pregnancy or weighing less than 28 ounces (700-800 grams).
PDA affects up to 80% of micropreemies, keeping them on ventilators longer and increasing the risk of lung disease. It can also lead to gastrointestinal problems and affect neurological development. That’s why closing the opening is critical.
“It’s a hard decision to make because many babies will survive with the PDA, or it may get smaller,” he said. While there is medication available to treat PDA, it’s often unsuccessful and has its own risk of kidney complications. Still, given the risk of open-chest surgery in such a small baby, “many surgeons would choose to continue to manage the baby medically,” Law said.
That changed in 2019 with the approval of the Amplatzer Piccolo Occluder, a pea-sized device that a cardiologist can snake through the femoral vein and into the heart via a catheter. “With this device, we now have the opportunity to intervene in a minimally invasive fashion with much less insult to the baby and a much lower risk of serious complications and still get the PDA closed,” McMahon said.
The occluder also allows them to avoid the artery, which they use to close PDAs in full-term or larger premature babies. In such tiny babies, however, putting a catheter through the artery could cause significant damage. “It’s part of the miracle of this device that we don’t have to access the artery,” McMahon said. “It’s much safer going in through the vein.”
Unlike most catheterization procedures, implanting the occlusion device requires a team of specialists, including neonatology, the cardiac catheterization team and anesthesiology, among others. “They’re fragile babies at risk just for the exposure and movement,” Law said. To date, the team has implanted the device in more than 20 babies.
“Not only will the device keep more of these tiny babies alive,” he said, “but, hopefully, it will result in more micropreemies who get to the end of the first year of life with fewer difficulties like chronic lung disease, GI tract disease and neurodevelopmental problems.”
“Any little thing that you can help these babies do better in the first year of life, so they are less dependent on medical technology and even less damaged from the care required to keep them alive,” McMahon said, “ends up in a better baby in the future.”