Nav: Home

New findings on embryonic heart valves may prevent congenital heart defects in newborns

January 05, 2016

ITHACA, N.Y. - Cornell biomedical engineers have discovered natural triggers that could reduce the chance of life-threatening, congenital heart defects among newborn infants. Those triggers can override developmental, biological miscues, leading to proper embryonic heart and valve formation.

More than 40,000 babies in the United States - or about 1 in 100 births - are born annually with a congenital heart defect, making it the most common defect, according to the Children's Heart Foundation.

"The heart is the first organ to form in the embryo. It morphs dynamically and rapidly all the while pumping nutrients to the developing body," said senior author Jonathan Butcher, associate professor at Cornell's Nancy E. and Peter C. Meinig School of Biomedical Engineering.

The early embryonic heart originates as a looped tube, without valves or pumping chambers. During the last few weeks of the first trimester, these heart chambers form, but need something to maintain one-way blood flow.

"Wispy globular masses (called cushions because of their shape in the heart wall) need to condense and elongate to form thin robust leaflets capable of fast and resilient opening and closing," Butcher said. "It is this maturation process that's likely disrupted in many clinical cases."

Until this study, scientists did not know how - or if - mechanical forces drove the biological remodeling of cushions into valves. Medical science understood that the embryonic heart needed blood flow to grow, but the valve component's role was not entirely understood, Butcher said.

The researchers found that cyclic stretches and stressing forces activate sensitive enzymes called GTPases, specifically RhoA and Rac1, which coordinate the embryonic heart's maturation. Without the enzymes activating at the proper times, heart valves do not form correctly.

"We identified a mechanism that transduced - or translated - a mechanical force into a biological response," Butcher said. "That biological response over time creates these thin, flexible, formative leaflets. If this tissue fails to get thinner, that's a problem. If the tissue fails to elongate, that's a problem. And these are all problems we see in the clinic."

This work lays a foundation for hemodynamically informed surgical interventions to potentially retard valve malformation - or to restore it, Butcher said.
-end-
The research, which is published in Current Biology, was supported by the National Science Foundation, the National Institutes of Health and the American Heart Association.

Cornell University has television, ISDN and dedicated Skype/Google+ Hangout studios available for media interviews.

Cornell University

Related Congenital Heart Defects Articles:

Faulty signalling pathway linked to congenital heart condition
Faulty signalling pathway causes the heart to develop unnaturally while in the embryo stage, according to Duke-NUS Medical School researchers.
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.
Greater prevalence of congenital heart defects in high intensity oil and gas areas
Mothers living near more intense oil and gas development activity have a 40-70% higher chance of having children with congenital heart defects (CHDs) compared to those living in areas of less intense activity, according to a new study from researchers at the Colorado School of Public Health.
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.
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.
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.
CVIA special issue on adult congenital heart disease
The new journal Cardiovascular Innovations and Applications (CVIA) has just published the first issue of Volume 3.
Getting to the heart of congenital cardiac defects
Heart defects are the most common type of birth defect, and can be caused by mutations in the gene CHD4.
More Congenital Heart Defects News and Congenital Heart Defects Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Rethinking Anger
Anger is universal and complex: it can be quiet, festering, justified, vengeful, and destructive. This hour, TED speakers explore the many sides of anger, why we need it, and who's allowed to feel it. Guests include psychologists Ryan Martin and Russell Kolts, writer Soraya Chemaly, former talk radio host Lisa Fritsch, and business professor Dan Moshavi.
Now Playing: Science for the People

#538 Nobels and Astrophysics
This week we start with this year's physics Nobel Prize awarded to Jim Peebles, Michel Mayor, and Didier Queloz and finish with a discussion of the Nobel Prizes as a way to award and highlight important science. Are they still relevant? When science breakthroughs are built on the backs of hundreds -- and sometimes thousands -- of people's hard work, how do you pick just three to highlight? Join host Rachelle Saunders and astrophysicist, author, and science communicator Ethan Siegel for their chat about astrophysics and Nobel Prizes.