Tag Archive for: sub-Saharan Africa

echocardiogram

AI may revolutionize rheumatic heart disease early diagnosis

echocardiogram

Researchers at Children’s National Hospital have created a new artificial intelligence (AI) algorithm that promises to be as successful at detecting early signs of rheumatic heart disease (RHD) in color Doppler echocardiography clips as expert clinicians.

Researchers at Children’s National Hospital have created a new artificial intelligence (AI) algorithm that promises to be as successful at detecting early signs of rheumatic heart disease (RHD) in color Doppler echocardiography clips as expert clinicians. Even better, this novel model diagnoses this deadly heart condition from echocardiography images of varying quality — including from low-resource settings — a huge challenge that has delayed efforts to automate RHD diagnosis for children in these areas.

Why it matters

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.

Though widely eradicated in nations such as the United States, rheumatic fever remains prevalent in developing countries, including those in sub-Saharan Africa. Recent studies have shown that, if detected soon enough, a regular dose of penicillin may slow the development and damage caused by RHD. But it has to be detected.

The hold-up in the field

Diagnosing RHD requires an ultrasound image of the heart, known as an echocardiogram. However, ultrasound in general is very variable as an imaging modality. It is full of texture and noise, making it one of the most challenging to interpret visually. Specialists undergo significant training to read them correctly. However, in areas where RHD is rampant, people who can successfully read these images are few and far between. Making matters worse, the devices used in these low resource settings have their own levels of varying quality, especially when compared to what is available in a well-resourced hospital elsewhere.

The research team hypothesized that a novel, automated deep learning-based method might detect successfully diagnose RHD, which would allow for more diagnoses in areas where specialists are limited. However, to date, machine learning has struggled the same way the human eye does with noisy ultrasound images.

Children’s National leads the way

Using approaches that led to successful objective digital biometric analysis software for non-invasive screening of genetic disease, researchers at the Sheikh Zayed Institute for Pediatric Surgical Innovation, including medical imaging scientist Pooneh Roshanitabrizi, Ph.D., and Marius Linguraru, D.Phil., M.A., M.Sc., principal investigator, partnered with clinicians from Children’s National Hospital, including Craig Sable, M.D., associate chief of Cardiology and director of Echocardiography, and cardiology fellow Kelsey Brown, M.D., who are heavily involved in efforts to research, improve treatments and ultimately eliminate the deadly impacts of RHD in children. The collaborators also included cardiac surgeons from the Uganda Heart Institute and cardiologists from Cincinnati Children’s Hospital Medical Center.

Dr. Linguraru’s team of AI and imaging scientists spent hours working with cardiologists, including Dr. Sable, to truly understand how they approach and assess RHD from echocardiograms. Building the tool based on that knowledge is why this tool stands apart from other efforts to use machine-learning for this purpose. Orienting the approach to the clinical steps of diagnosis is what led to the very first deep learning algorithm that diagnoses mild RHD with similar success to the specialists themselves. After the platform was built, 2,136 echocardiograms from 591 children treated at the Uganda Heart Institute fed the learning algorithm.

What’s next

The team will continue to collect data points based on clinical imaging data to refine and validate the tool. Ultimately, researchers will look for a way that the algorithm can work directly with ultrasound/echocardiogram machines. For example, the program might be run through an app that sits on top of an ultrasound device and works on the same platform to communicate directly with it, right in the clinic. By putting the two technologies together, care providers on the ground will be able to diagnose mild cases and prescribe prophylactic treatments like penicillin in one visit.

The first outcomes from the program were showcased in a presentation by Dr. Roshanitabrizi at one of the biggest and most prestigious medical imaging and AI computing meetings — the 25th International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI).

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: