“It’s unfathomable, then, that we could make things worse by limiting or taking away the child’s health care coverage.”
Roughly 40,000 infants are born each year with a heart defect. The one that struck Mr. Kimmel’s son is called Tetralogy of Fallot with pulmonary atresia; it affects about seven of every 100,000 babies born alive and accounts for 2 percent of all congenital heart defects.
The condition is hard to miss: The child is often born blue because the passage from the heart to the lungs is completely blocked. Blood cannot get to the lungs, where it would be oxygenated.
The infant is alive only because a passageway to the lungs during fetal development remains, letting blood get through. It will close, though, and the condition can be fatal without immediate surgery, which can cost $100,000.
Roughly 90 percent of these children will survive to age 18, but the initial surgery is just a temporary fix. Doctors usually have to operate several times over the years. And people with the condition need regular care from experts.
“It’s a disease of a lifetime,” said Dr. Yuli Kim, director of the adult congenital heart disease center at the University of Pennsylvania.
Before the passage of the Affordable Care Act in 2010, federal law required employer-sponsored plans to cover newborns regardless of their health status as long as their parents enrolled them within 30 days, said Karen Pollitz, a senior fellow at the Kaiser Family Foundation.
If parents switched jobs, their new insurers could not impose waiting periods or charge more for sick newborns.
But things were different for parents who bought their insurance individually.
All 50 states had laws requiring newborns to be covered under a parent’s insurance policy and not to be charged more if they were sick, if they were enrolled within 30 days. But if a parent switched plans after a baby’s birth, the new insurer could refuse to cover the care for an ill infant for an initial period of time or charge more, Ms. Pollitz said.
They could also do so if the parents were uninsured to begin with.
Lifetime limits on coverage were a problem, too. In both individual and employer-sponsored plans, some critically ill children met policy limits within the first few years of their lives.
Ms. Pollitz pointed out, however, that about half of all newborns were and still are insured by Medicaid, “which basically says whatever the kid needs is covered.” Many infants with severe congenital defects require home care provided under the program, as well.
Under the Republican repeal-and-replace bill, the biggest concern for seriously ill newborns may be cuts to the Medicaid program. The Republican plan would give states a choice between a fixed annual sum per recipient or a block grant, either of which would almost certainly lead to major limitations in coverage over time.
The bill would also allow states to opt out of several consumer protections, including the Affordable Care Act’s ban on insurance companies’ charging higher premiums to people with pre-existing medical conditions.
That could affect the roughly 8 percent of Americans who rely on the individual insurance market, though only if they had been uninsured for 63 days or more in the previous year.
Under this plan, families with sick children who rely on individual coverage would “have to be meticulous about signing up at every open enrollment and never missing a payment,” Ms. Pollitz said.
“One slip-up, and you’re back in the underwritten pool again and could be charged an unaffordable amount.”
The Republican bill would also let states allow insurers to offer skimpier coverage than the Affordable Care Act requires, and it would provide smaller premium tax credits for many Americans.
“You’re going to have a certain level of income to even be able to afford the coverage in the first place,” said Sabrina Corlette, a research professor at Georgetown University.
Even now, parents of newborns with severe heart defects struggle for care.
Ideally, infants with congenital heart defects receive surgery in specialized medical centers, said Dr. Gerald Marx, a pediatric cardiologist at Boston Children’s Hospital, which performs about 1,400 heart operations each year. Outcomes are better if the surgeon and medical center are highly experienced.
Not every state has specialized congenital heart disease centers, yet families often have insurance policies that do not cover medical care outside their state.
“When the insurers won’t pay for it, very tragically, they end up just not coming,” Dr. Marx said.
The future worries Elizabeth Swift, of Billerica, Mass., whose son, James, now 7, was born with the same heart defect as Mr. Kimmel’s son.
She and her husband were so stressed and distracted after his birth and open-heart surgery that they missed the 30-day window to inform their insurer in order to guarantee coverage. The insurance company refused to cover their son’s care.
“I was getting bills for hundreds of thousands of dollars in the mail,” she said. “I just cried and said, ‘I can’t deal with this now.’”
Eventually, she managed to obtain coverage for her son from the state. When the Affordable Care Act passed, her husband’s company insurance agreed to cover James.
Now she worries about what might happen to James’s insurance and that of other children with severe congenital defects if the Republican bill passes.
What if lawmakers restore insurers’ ability to impose lifetime caps on the amount they will pay? What might happen in the long term, after James turns 26 and can no longer be covered under his parents’ insurance?
“I am praying,” Mrs. Swift said.
An earlier version of this article misspelled the given name of a cardiologist at the University of Pennsylvania. She is Dr. Yuli Kim, not Yuri.