Tag Archive for: heart disease

Dr. Sable performing an echocardiogram in Uganda

Penicillin slows impacts of rheumatic heart disease in Ugandan children

Dr. Sable performing an echocardiogram in Uganda

“We know from previous studies that though it is not always well-documented, sub-Saharan Africa continues to have some of the highest numbers of people with rheumatic heart disease and the highest numbers of people dying from it,” said Craig Sable, M.D., associate chief of Cardiology at Children’s National Hospital and co-senior author of the study. “This study is the first large-scale clinical trial to show that early detection coupled with prophylactic treatment of penicillin is feasible and can prevent rheumatic heart disease from progressing and causing further damage to a child’s heart.”

Penicillin, a widely available and affordable antibiotic, may be one key to turning the tide on the deadly impacts of rheumatic heart disease (RHD) for children in developing nations. This according to the new findings of a large-scale, randomized controlled trial completed in Uganda and published in the New England Journal of Medicine.

The most devastating feature of RHD is severe heart valve damage that is caused by rheumatic fever — a condition that results from the body’s immune system trying to fight poorly treated, repeat infections from streptococcus bacteria, also known as strep throat. Though widely eradicated in nations such as the United States due to the swift detection and treatment of strep throat, rheumatic fever remains prevalent in developing countries including those in sub-Saharan Africa. Current estimates are that 40.5 million people worldwide live with rheumatic heart disease, and that it kills 306,000 people every year. Most of those affected are children, adolescents and young adults under age 25.

“We know from previous studies that though it is not always well-documented, sub-Saharan Africa continues to have some of the highest numbers of people with rheumatic heart disease and the highest numbers of people dying from it,” said Craig Sable, M.D., associate chief of Cardiology at Children’s National Hospital and co-senior author of the study. “This study is the first large-scale clinical trial to show that early detection coupled with prophylactic treatment of penicillin is feasible and can prevent rheumatic heart disease from progressing and causing further damage to a child’s heart.”

The study was led by an international panel of pediatric cardiac experts from institutions including Children’s National, Cincinnati Children’s Medical Center, the Uganda Heart Institute and Murdoch Children’s Research Institute in Melbourne, Australia.

“Our study found a cheap and easily available penicillin can prevent progression of latent rheumatic heart disease into more severe, irreversible valve damage that is commonly seen in our hospitals with little or no access to valve surgery,” said co-lead author Emmy Okello, M.D., chief of Cardiology at the Uganda Heart Institute.

To Andrea Beaton, M.D., associate professor of Cardiology at Cincinnati Children’s and co-lead author, this is the first contemporary randomized controlled trial in rheumatic heart disease. “The results are incredibly important on their own, but also demonstrate that high-quality clinical trials are feasible to address this neglected cardiovascular disease,” she said.

Beaton et al. named the trial Gwoko Adunu pa Lutino (GOAL), which means “protect the heart of a child.” The study enrolled 818 Ugandan children and adolescents ages 5 to 17 years old who were diagnosed with latent rheumatic heart disease to see if an injection of penicillin was effective at preventing their heart condition from worsening.

“There are many challenges with recruitment and retention of trial participants in areas like our study region in Uganda,” said Dr. Sable. “But it is critical to work together and overcome barriers, because we must study these treatments in the people most affected by the condition to understand how they, and others like them, may benefit from the findings.”

Of the 799 participants who completed the trial, the group receiving a prophylactic injection of penicillin (399 volunteers) had three participants show evidence of worsened rheumatic heart disease on repeat echocardiogram after two years. In contrast, 33 of the 400 volunteers in the control group, who received no treatment, showed similar progression on echocardiogram results.

Professor Andrew Steer, who is theme director of Infection and Immunity at Murdoch Children’s Research Institute in Melbourne and who served as senior author of the study, said screening for latent rheumatic heart disease was critical to stop progression because heart valve damage was largely untreatable. “Most patients are diagnosed when the disease is advanced and complications have already developed. If patients can be identified early, there is an opportunity for intervention and improved health outcomes.”

The results were shared in a special presentation at the American Heart Association’s Scientific Sessions on the same day that the findings were published in the New England Journal of Medicine.

The trial was supported by the Thrasher Pediatric Research Fund, Gift of Life International, Children’s National Hospital Foundation: Zachary Blumenfeld Fund, Children’s National Hospital Race for Every Child: Team Jocelyn, the Elias/Ginsburg Family, Wiley-Rein LLP, Phillips Foundation, AT&T Foundation, Heart Healers International, the Karp Family Foundation, Huron Philanthropies and the Cincinnati Children’s Hospital Heart Institute Research Core.

Learn more about the challenges of rheumatic heart disease in sub-Saharan Africa and other developing parts of the world through the Rheumatic Heart Disease microdocumentary series:

Ugandan boy in hospital bed

Acute rheumatic fever often goes undiagnosed in sub-Saharan Africa

Ugandan boy in hospital bed

Despite low numbers of documented acute rheumatic fever cases in sub-Saharan Africa, the region continues to show some of the highest numbers of people with, and dying from, rheumatic heart disease, the serious heart damage caused by repeat instances of rheumatic fever.

Despite low numbers of documented acute rheumatic fever cases in sub-Saharan Africa, the region continues to show some of the highest numbers of people with, and dying from, rheumatic heart disease, the serious heart damage caused by repeat instances of rheumatic fever. A population-based study in the Lancet Global Health collected evidence of acute rheumatic fever in two areas of Uganda, providing the first quantifiable evidence in decades that the disease continues to take a deadly toll on the region’s people.

“These findings matter. Access to life-saving heart surgery is only available to a very small fraction of the hundreds of thousands of patients in Africa who have irreversible heart damage from rheumatic heart disease,” says Craig Sable, M.D., associate chief of Cardiology at Children’s National Hospital and one of the senior authors of the study. “It’s time to focus upstream on capturing these conditions sooner, even in low-resource settings, so we can implement life-sustaining and cost-saving preventive treatments that can prevent further heart damage.”

The authors, who hail from Uganda and several institutions around the United States, including Children’s National and Cincinnati Children’s Hospital Medical Center, note this is the first study to use an active case-finding strategy for diagnosing acute rheumatic fever. They also note that raising awareness in the community and among its healthcare workers while also finding new ways to overcome some of the diagnostic challenges in these low-resource settings greatly improved diagnosis and treatment of the condition.

The study also described clinical characteristics of children ages 5 to 14 presenting with both definitive and possible acute rheumatic fever, providing further clinical data points to help healthcare workers in these communities differentiate between this common infection and some of the other frequently diagnosed conditions in the region.

“With this study, we can now confidently dismiss the myth that acute rheumatic fever is rare in Africa,” the authors write. “It exists at elevated rates in low-resource settings such as Uganda, even though routine diagnosis remains uncommon. While these incidence data have likely underestimated the cases of acute rheumatic fever in two districts in Uganda, they show that opportunity exists to improve community sensitization and healthcare worker training to increase awareness of acute rheumatic fever. Ultimately this leads to diagnosing more children with the condition before they develop rheumatic heart disease, so that they can be offered secondary prophylaxis with penicillin.”

Children with suspected acute rheumatic fever participated in this population-based study. Data was collected over 12 months in Lira district (January 2018 to December 2018) and over nine months (June 2019 to February 2020) in Mbarara district.

Follow-up of children diagnosed in this study will provide more data on the outcomes of acute rheumatic fever, including a better understanding of the risk for a child to develop rheumatic heart disease.

This work was funded by the American Heart Association Children’s Strategically Focused Research Network Grant #17SFRN33670607 and by DEL‐15‐011 to THRiVE‐2 and General Electric.

Learn more about the challenges of rheumatic heart disease in sub-Saharan Africa and other developing parts of the world through the Rheumatic Heart Disease microdocumentary series:


Cholesterol plaque in artery

Looking for atherosclerosis’ root cause

Cholesterol plaque in artery

A multi-institutional team led by research faculty at Children’s National in Washington, D.C., finds that extracellular vesicles derived from kids’ fat can play a pivotal role in ratcheting up risk for atherosclerotic cardiovascular disease well before any worrisome symptoms become visible.

According to the Centers for Disease Control and Prevention, about one in five U.S. kids aged 6 to 19 is obese, boosting their risk for a variety of other health problems now and later in life.

One of these is atherosclerosis, a term that translates literally as hardening of the arteries. Atherosclerosis causes blood vessels that carry oxygen-rich blood throughout the body to become inflamed. White blood cells called macrophages settle in the vessel wall, which becomes overloaded with cholesterol. A plaque forms that restricts blood flow. But it remains a mystery how fat cells residing in one place in the body can trigger mayhem in cells and tissues located far away.

Small, lipid-lined sacs called extracellular vesicles (EVs), released by cells into the bloodstream, are likely troublemakers since they enable intercellular communication. Now, a multi-institutional team led by research faculty at Children’s National in Washington, D.C., finds that EVs derived from kids’ fat can play a pivotal role in ratcheting up risk for atherosclerotic cardiovascular disease well before any worrisome symptoms become visible. What’s more, the team showed that EVs found in the body’s fat stores can disrupt disposal of cholesterol in a variety of kids, from lean to obese, the team reports online July 22, 2019, in the Journal of Translational Medicine.

“We found that seven specific small sequences of RNA (microRNA) carried within the extracellular vesicles from human fat tissue impaired the ability of white blood cells called macrophages to eliminate cholesterol,” says Robert J. Freishtat, M.D., MPH, senior scientist at the Center for Genetic Medicine Research at Children’s National and the study’s senior author. “Fat isn’t just tissue. It can be thought of as a metabolic organ capable of communicating with types of cells that predispose someone to develop atherosclerotic cardiovascular disease, the leading cause of death around the world.”

Research scientists and clinicians from Children’s National, the George Washington University, NYU Winthrop Hospital and the National Heart, Lung and Blood Institute collaborated to examine the relationship between the content of EVs and their effect on macrophage behavior. Their collaborative effort builds on previous research that found microRNA derived from fat cells becomes pathologically altered by obesity, a phenomenon reversed by weight-loss surgery.

Because heart disease can have its roots in adolescence, they enrolled 93 kids aged 12 to 19 with a range of body mass indices (BMIs), including the “lean” group, 15 youth whose BMI was lower than 22 and the “obese” group, 78 youths whose BMI was in the 99th percentile for their age. Their median age was 17. Seventy-one were young women. They collected visceral adipose tissue during abdominal surgeries and visited each other’s respective labs to perform the experiments.

“We were surprised to find that EVs could hobble the macrophage cholesterol outflow system in adolescents of any weight,” says Matthew D. Barberio, Ph.D., the study’s lead author, a former Children’s National scientist who now is an assistant professor at the George Washington University’s Milken Institute School of Public Health. “It’s still an open question whether young people who are healthy can tolerate obesity—or whether there are specific differences in fat tissue composition that up kids’ risk for heart disease.”

The team plans to build on the current findings to safeguard kids and adults against future cardiovascular risk.

“This study was a huge multi-disciplinary undertaking,” adds Allison B. Reiss, M.D., of NYU Winthrop Hospital and the study’s corresponding author. “Ultimately, we hope to learn which properties belonging to adipose tissue EVs make them friendly or unfriendly to the heart, and we hope that gaining that knowledge will help us decrease morbidity and mortality from heart disease across the lifespan.”

In addition to Dr. Freishtat, additional study co-authors include Samuel B. Epstein, Madeleine Goldberg, Sarah C. Ferrante, and Evan P. Nadler, M.D., director of the Bariatric Surgery Program, all of Children’s National’s Center for Genetic Medicine Research; Lead Author, Matthew D. Barberio, of Millken Institute School of Public Health at the George Washington University; Lora J. Kasselman, Heather A. Renna, Joshua DeLeon, Iryna Voloshyna, Ashley Barlev, Michael Salama and Allison B. Reiss, all of NYU Winthrop Hospital; and Martin P. Playford and Nehal Mehta, of the National Heart, Lung and Blood Institute.

Financial support for research described in this post was provided by the National Institutes of Health National Center for Advancing Translational Sciences under award number UL1TR000075, the National Heart, Lung and Blood Institute under award number Z1AHL-06193-4, the American Heart Association under award number 17POST33670787, the Clark Charitable Foundation, the Elizabeth Daniel Research Fund, and Robert Buescher.

heart and medical equiptment

How much do you know about congenital heart defects?


Relationship between sedentary time and youth cardiovascular health

Heart disease is the leading cause of death in the United States, yet for many individuals it is preventable through modifications in diet, physical activity, and sedentary time – all major risk factors. Jacob Hartz, M.D., M.P.H., a cardiology fellow at Children’s National Health System, presented findings from his research on youth cardiovascular health during the American Heart Association (AHA) Scientific Sessions, held November 12-16 in New Orleans. The AHA Scientific Sessions featured the latest developments in science and cardiovascular clinical practice, including all aspects of basic, clinical, population, and translational science. Dr. Hartz spoke on “The Relationship Between Clustering of Cardiovascular Health Behaviors and Physical Fitness Among U.S. Adolescents – Data from the National Health and Nutrition Examination Survey,” and shared how grouping children with risk factors into clusters enabled researchers to pinpoint sedentary time as the leading predictor of heart health.

Read more about Children’s National AHA Scientific Sessions speakers.

Link between population health and heart disease

Gerard Martin

Although clinical advances have improved treatments and mortality among patients with cardiovascular disease, heart disease remains the leading cause of death worldwide. Gerard Martin, M.D., cardiologist and medical director of Global Health at Children’s National and Chair of the American College of Cardiology’s Population Health Policy and Promotion Committee shares how cardiologists can improve outcomes by focusing on the link between population health and heart disease in a just-published article in Cardiology.

Read more.

Robert J. Freishtat

A game changer for detecting complications from obesity

Robert J. Freishtat

The work that Children’s National Health System physician-scientist Robert J. Freishtat, M.D., M.P.H., and colleagues are doing could soon be a game changer when it comes to early intervention and prevention of obesity-related illnesses.

They already knew there’s a direct relationship between the amount of visceral adipose, or belly fat, a person has and development of some of the most common and life-threatening complications of obesity, including cardiovascular disease and the insulin resistance that leads to diabetes. What remained unclear, until recently, were the precise mechanisms for how the increase in belly fat triggers the onset of additional disease.

Dr. Freishtat, senior author of “Adipocyte-Derived Exosomal miRNAs: A Novel Mechanism for Obesity-Related Disease,” published by Pediatric Research, studies the adipocytes, or fat cells, of visceral adipose in both lean and obese patients to understand exactly how these fat cells can and do wreak havoc — not just locally but throughout the body. Cells leverage exosomes to communicate among themselves, but in overweight patients those cellular communications can go awry.

“As the body’s visceral fat grows, somewhere on the path to obesity the fat cells change and begin to release different exosomes than lean adipose cells do. These new messages disrupt some important processes that eventually prevent the body from effectively dealing with sugar and cholesterol,” says Dr. Freishtat, chief of Emergency Medicine at Children’s National, and associate professor of Pediatrics, Emergency Medicine, and Integrative Systems Biology at the George Washington University.

Dr. Freishtat describes exosomes as “biological tweets”— short messages shed by all cells that allow for intercellular communication and alter gene expression. In the case of the adipocytes that exist in large quantities of visceral fat, these “tweets” actually cause the downregulation of proteins impacting two key signaling pathways — TGF-β and Wnt/β-catenin — associated with controlling chronic inflammation and fibrotic disease throughout the body. These signaling changes make morbidly obese patients more vulnerable to systemwide issues, such as cholesterol accumulation and changes to how the liver processes fat.

Details of the study

The study authors surgically collected fat tissue from lean and obese female patients aged 11 to 19 and used modified bead-based flow cytometry to separate, identify, and compare the exosomal RNA shed by the fat cells in both lean and obese samples. To confirm the unique impact of the obese adipose exosomes on gene expression, the research team then exposed lung cells in vivo to the exosomes shed by both lean and obese adipose. They measured the impact of exposure and uptake on a single receptor type — activin receptor type-2B — known to have a major influence on the TGF-β pathway. The exosomes from obese adipose caused the receptor to slow down, leading to significant changes in the function of the TGF-β pathway.

The team continues to explore how the exosomes shed from excess amounts of visceral adipose spread throughout the body and how the function of organs such as the liver, the heart, and the brain are impacted by the migrating fat cells.

A Look into the future

Successfully identifying and isolating these exosomes also has opened the door to developing a test to detect them, an idea that may permit even earlier intervention to delay or prevent the onset of obesity-related illnesses.

“It is entirely plausible, and is on its way to happening very soon, that someone could walk into their physician’s office for a routine physical and, via a urine test, find out that they are on the road to some dangerous additional side effects of significant weight gain,” says Dr. Freishtat. “That type of early detection could really be a game changer for the millions of Americans who are on track to developing heart, liver, and other diseases resulting from morbid obesity.”