CARDIOLOGY
Why Hearts Fail
Can a team of pediatric heart researchers identify why some children ’ s hearts fail after single ventricle surgery and identify potential therapeutic drugs to stop that progression ?
A team of doctors at Children ’ s Hospital Colorado ’ s Heart Institute is working to uncover the exact mechanisms that lead to heart failure for some children after single ventricle surgery . The hope is to not only identify potential drugs to slow the progression , but ultimately prevent the need for a heart transplant altogether .
The University of Colorado Anschutz Medical Campus is home to one of the largest IRB-approved cardiac tissue biobanks in the country , where Shelley Miyamoto , MD , and her team receive freshly explanted heart tissue to study . This area of pediatric research is particularly valuable because what we know about heart failure in adults is vastly different than what we know about heart failure in children . As Dr . Miyamoto puts it , “ There ’ s something different about pediatric heart failure ,” and the team at Children ’ s Colorado is determined to figure out what .
One of the most common severe congenital heart diseases is single ventricle disease , where a baby is born with only one pumping chamber of the heart . The most common treatment path for single ventricle babies is a series of three surgeries over the first five years of the child ’ s life to reroute the heart ’ s blood flow . After the third surgery , known as the Fontan procedure , an entire team of experts in the Children ’ s Colorado Fontan multidisciplinary clinic partner with the child ’ s primary cardiologist to support the child through the next hurdles . The team watches for complications in the lungs and liver , tests for neurodevelopmental issues and monitors patients for the signs of heart failure that could require an eventual heart transplant .
Dr . Miyamoto and her team are working to understand why heart failure happens to these young children . She has spent nearly two decades at Children ’ s Colorado and is the top-funded child health research investigator at the Heart Institute . She is also a valuable mentor to Anastacia “ Tasha ” Garcia , PhD , Stephanie Nakano , MD , and Kathryn Chatfield , MD , PhD , among others . Together , they are making significant contributions to this area of research .
UNCOVERING ANSWERS
When Dr . Garcia arrived at Children ’ s Colorado nearly eight years ago , Dr . Miyamoto saw an opportunity to bridge the world of basic science and clinical translational research for single ventricle heart disease . At the time , researchers knew that adults with heart failure typically have mitochondrial dysfunction , where the energy factory of the cells is not functioning properly . But that was never proven true for single ventricle pediatric patients — until now .
“ Until recently , very little was known about the transition to heart failure in this unique population ,” Dr . Garcia explains . “ But over the past several years , our lab and others have really characterized what happens at a molecular level .”
Dr . Garcia has worked her entire professional career to identify mechanisms of heart failure progression and to assess if there is mitochondrial dysfunction in these failing single ventricle hearts . And according to Dr . Miyamoto , Dr . Garcia ’ s latest paper , published earlier this year in Journal of the American College of Cardiology , is the first to show proof of this . Her team found that failing single
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