Nav: Home

Careful monitoring of children following cardiac surgery may improve long-term outcomes

October 03, 2019

In a medical records study covering thousands of children, a U.S.-Canadian team led by researchers at Johns Hopkins Medicine concludes that while surgery to correct congenital heart disease (CHD) within 10 years after birth may restore young hearts to healthy function, it also may be associated with an increased risk of death and kidney failure within a few months or years after surgery.

Although deaths related to end-stage kidney disease (ESKD) were rare in the total population studied, the researchers report that overall mortality was up to 10 times more prevalent in those who had cardiac repair surgeries compared with the general population.

"Congenital heart disease is among the most common forms of birth defects and successful surgical interventions are usually performed before the age of 2; however, the specific risks of long-term, negative outcomes -- especially deaths resulting from ESKD -- are basically unknown for this population," says Chirag Parikh, M.D., Ph.D., director of the Division of Nephrology at the Johns Hopkins University School of Medicine and lead author of the new paper. "So, we conducted what is believed to be the largest study with the longest follow-up ever of these children to better understand these risks and guide the development of methods to help them lessen the chance of kidney-related mortality."

The study is published in the October 2019 issue of the Clinical Journal of the American Society of Nephrology (CJASN).

Parikh says that clinical outcome studies in recent years provide evidence that surgical repair of heart problems during the first decade of life does not cure the underlying congenital defect, and that pathological changes can continue in the cardiovascular system and the kidneys. These changes may result in impaired heart function, decreased blood flow and oxygen delivery to the kidneys, and higher-than-normal pressure (hypertension) in the veins that drain the kidneys of filtered blood and return it to the heart for oxygenation.

In an attempt to more precisely measure the problem of ESKD after childhood heart surgery, Parikh and his colleagues looked at medical records from seven linked Canadian patient databases. Since Canadians have universal access to health care services, the study population was free of disparities and differences in the treatment and follow-up care they received.

From the list of all babies born in Ontario, Canada, between April 1, 2012, and March 31, 2015, the researchers selected 3,600 children who had surgeries to repair CHD within 10 years of birth, and matched them with 36,000 others who did not have the congenital condition nor any procedures performed on their hearts. Most of the patients who had repair surgery were prematurely born males with low birth weights and around 150 days old at the time of their first surgery.

Cardiac repair surgeries performed on the patients were ranked from 1 to 4 in increasing complexity, with 43% being listed at categories 3 or 4, and including some more complex than category 4. The two most commonly seen procedures (72%) were closure of a hole between the atria (upper chambers of the heart) or between the ventricles (lower chambers of the heart).

Both the cardiac repair surgery and the non-surgery subjects were followed medically for up to 13 years, with data collected until death, diagnosis of ESKD or the end of the study (March 31, 2015). Of the 3,600 subjects who had surgery, 140 (3.89%) died and 52 (1.44%) developed ESKD. These numbers were significantly higher than those among the 36,000 who did not have CHD or surgery. In the latter group, 35 (0.10%) died -- a rate four times lower than the CHD patients -- and six (0.02%) developed ESKD, a rate nearly nine times lower.

The mortality incidence rate -- the total number of deaths from all causes during the study period divided by the cumulative time in years for all of the patients participating (known as person-years) -- for the cardiac repair surgery subjects was 69 deaths per 10,000 person-years. By contrast, the rate for the nonsurgery group was two deaths per 10,000 person-years.

The researchers say this indicates that children who had cardiac repair surgery at a young age were 34.5 times more likely to die within a decade after that surgery than those in the general population.

The ESKD incident rates also showed significantly higher risk of developing kidney failure as an outcome of early age CHD repair surgery. For the surgery patients, the incident rate was 26 cases per 10,000 person-years compared with 0.3 cases per 10,000 person-years -- a difference of 867-to-1.

"We also saw that the more complex the cardiac surgery performed, the higher the risk of both death from any causes and for developing ESKD," Parikh says. "In the most extreme case, patients who had surgery to correct a hypoplastic left heart -- a severe defect where the left side of the heart is underdeveloped -- were 10 times more likely to develop ESKD than those who had other congenital heart conditions remedied."

Parikh cautions that medical records studies that "look back" at patient histories have limitations, but says that the research team's findings should be useful in guiding better long-term care for those at highest risk for ESKD and shortened lifespans.

"For now, we recommend that children who have cardiac repair early in their lives be monitored more closely for signs of developing ESKD," he says. "Future research should look for early biomarkers of kidney damage and develop computer models that could help us identify those most at risk."
-end-
Including Parikh, the other members of the research team are Heather Thiessen-Philbrook, M.MATH, and Allen Everett, M.D., from the Johns Hopkins University School of Medicine (Baltimore, Maryland); Jason Greenberg, M.D., from Yale University (New Haven, Connecticut); Eric McArthur, M.Sc., from ICES (Toronto, Ontario, Canada); Ron Wald, M.D., C.M., from St. Michael's Hospital and the University of Toronto (Toronto, Ontario, Canada); Michael Zappitelli, M.D., M.Sc., from The Hospital for Sick Children (Toronto, Ontario, Canada); Rahul Chanchlani, M.D., from McMaster University (Hamilton, Ontario, Canada); and Amit X. Garg, M.D., Ph.D., from Western University (London, Ontario, Canada).

The study was supported by ICES, which is funded by an annual grant from the Ontario Ministry of Health and Long-Term Care (Toronto, Ontario, Canada). Parikh reports personal fees for consulting from Akebia Therapeutics Inc. and Genfit Biopharmaceutical Company, and other fees from Renaltix AI. None of the other authors have anything to disclose.

Johns Hopkins Medicine

Related Congenital Heart Disease Articles:

Telehealth effectively diagnoses/manages fetal congenital heart disease in rural patients
A recent study of 368 pregnant mothers, led by Bettina Cuneo, MD, director of perinatal cardiology and fetal cardiac telemedicine at Children's Hospital Colorado, found that fetal congenital heart disease (CHD) was correctly identified and successfully managed according to evidence-based risk stratification.
Uncorrected congenital heart disease may lead to increased risks in pregnant women
Pregnant women with congenital heart disease (CHD) who have not had surgery to repair their cardiac condition are more likely to experience cardiac events or maternal death, especially those with certain conditions in emerging countries, according to a study published Oct.
A new framework to study congenital heart defects
In a new study published in the scientific journal Nature, a team of researchers at the Gladstone Institutes, in collaboration with the University of Luxembourg, reveal for the first time the full spectrum of cells that come together to make a heart at the earliest stages of embryo formation.
Risk of cancer among children, young adults with congenital heart disease
National registry data in Sweden were used in this study that assessed the risk of developing cancer in children and young adults with congenital heart disease compared with healthy people in the general population from birth to age 41.
Congenital heart defects vastly increase risk of heart problems later in life
An infant born with a relatively simple heart defect is far more likely to develop heart problems as an adult, researchers at the Stanford University School of Medicine have discovered.
Human milk is a 'life-saving intervention' for infants with congenital heart disease
With a lower risk of serious complications and improved feeding and growth outcomes, human milk is strongly preferred as the best diet for infants with congenital heart disease (CHD), according to a research review in Advances in Neonatal Care, official journal of the National Association of Neonatal Nurses.
Climate change may increase congenital heart defects
The rise in temperatures stemming from climate change may increase the number of US infants born with congenital heart defects between 2025 and 2035.
Worse outcomes for Hispanic infants with critical congenital heart disease
Hispanic infants born with critical types of heart disease had significantly worse one-year outcomes than infants born to white mothers.
UA study: Sleep apnea, congenital heart disease may be deadly mix for hospitalized infants
Infants with congenital heart disease and central sleep apnea are four times more likely to die in the hospital, researchers find.
Newborns with congenital heart disease have enlarged kidneys
The hearts and brains of babies born with congenital heart disease are not the only organs affected by this common medical condition.
More Congenital Heart Disease News and Congenital Heart Disease Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#543 Give a Nerd a Gift
Yup, you guessed it... it's Science for the People's annual holiday episode that helps you figure out what sciency books and gifts to get that special nerd on your list. Or maybe you're looking to build up your reading list for the holiday break and a geeky Christmas sweater to wear to an upcoming party. Returning are pop-science power-readers John Dupuis and Joanne Manaster to dish on the best science books they read this past year. And Rachelle Saunders and Bethany Brookshire squee in delight over some truly delightful science-themed non-book objects for those whose bookshelves are already full. Since...
Now Playing: Radiolab

An Announcement from Radiolab