Cost-effectiveness analysis of rheumatic heart disease prevention strategies

Deep Learning in Heart Sound Analysis: From Techniques to Clinical Applications

Importance: Heart sound auscultation is a routinely used physical examination in clinical practice to identify potential cardiac abnormalities. However, accurate interpretation of heart sounds requires specialized training and experience, which limits its generalizability. Deep learning, a subset of machine learning, involves training artificial neural networks to learn from large datasets and perform complex tasks with intricate patterns. Over the past decade, deep learning has been successfully applied to heart sound analysis, achieving remarkable results and accumulating substantial heart sound data for model training. Although several reviews have summarized deep learning algorithms for heart sound analysis, there is a lack of comprehensive summaries regarding the available heart sound data and the clinical applications. Highlights: This review will compile the commonly used heart sound datasets, introduce the fundamentals and state-of-the-art techniques in heart sound analysis and deep learning, and summarize the current applications of deep learning for heart sound analysis, along with their limitations and areas for future improvement. Conclusions: The integration of deep learning into heart sound analysis represents a significant advancement in clinical practice. The growing availability of heart sound datasets and the continuous development of deep learning techniques contribute to the improvement and broader clinical adoption of these models. However, ongoing research is needed to address existing challenges and refine these technologies for broader clinical use.

Long-term antibiotic prophylaxis for prevention of rheumatic fever recurrence and progression to rheumatic heart disease

BACKGROUND

Rheumatic fever is a non-suppurative, inflammatory sequela of group A Streptococcus pharyngitis that can occur at two to four weeks after infection. Following an episode of rheumatic fever, there is a risk of developing rheumatic heart disease (RHD) later in life that carries significant risk of morbidity and mortality. RHD remains the largest global cause of cardiovascular disease in the young (age < 25 years). The historical literature provides inconclusive evidence that antibiotic prophylaxis is beneficial in reducing the risk of recurrence of rheumatic fever and development of RHD. Antibiotics are thought to work by reducing the carriage of group A Streptococcus and thus reducing the risk of infection. This review was commissioned by the World Health Organization (WHO) for an upcoming guideline.

OBJECTIVES

1. To assess the effects of long-term antibiotics versus no antibiotics (control) for secondary prevention of rheumatic fever recurrence and associated sequelae in people with previous rheumatic fever or RHD. 2. To assess the effects of long-term intramuscular penicillin versus long-term oral antibiotics for secondary prevention of rheumatic fever recurrence and associated sequelae in people with previous rheumatic fever or RHD.

SEARCH METHODS

We systematically searched CENTRAL, MEDLINE, Embase, Conference Proceedings Citation Index-Science, clinical trial registers, ISRCTN.com and reference lists without restrictions on language or date up to 10 March 2024.

SELECTION CRITERIA

We sought randomised controlled trials or quasi-randomised trials, described in any language, including participants with previous rheumatic fever and/or RHD of any age, based in community or hospital settings. Studies were included if they compared firstly antibiotic prophylaxis with no antibiotic prophylaxis, and, secondly, intramuscular penicillin prophylaxis versus oral antibiotic prophylaxis.

DATA COLLECTION AND ANALYSIS

We used standardised methodological, Cochrane-endorsed procedures and performed meta-analyses with risk ratios (RR) and Peto odds ratios (Peto OR). Our primary outcomes were recurrence of rheumatic fever, progression or severity of RHD and cardiac complications. Our secondary outcomes were obstetric complications (maternal and foetal events), mortality, treatment adherence, adverse events and acceptability to participants. We performed comprehensive assessments of risk of bias and certainty of evidence, applying the GRADE methodology.

MAIN RESULTS

We included 11 studies (seven RCTs and four quasi-randomised trials) including 3951 participants. The majority of the included studies were conducted in the USA, UK and Canada during the 1950s to 1960s. Most participants with previous rheumatic fever had been diagnosed using the modified Jones criteria (mJC) (four studies), were an average of 12.3 years of age and 50.6% male. We assessed the majority of the included studies to be at high risk of bias, predominantly relating to blinding and attrition bias. Comparison one: antibiotics versus no antibiotics Pooled meta-analysis of six RCTs provides moderate-certainty evidence that antibiotics overall (oral or intramuscular) probably reduce the risk of recurrence of rheumatic fever substantially (0.7% versus 1.7%, respectively) (risk ratio (RR) 0.39, 95% confidence interval (CI) 0.22 to 0.69; 1721 participants). People with early or mild RHD likely have the greatest capacity to benefit from intramuscular antibiotic prophylaxis (8.1%) compared to no antibiotics (0.7%) (RR 0.09, 95% CI 0.03 to 0.29; 1 study, 818 participants; moderate-certainty evidence). Antibiotics may not affect mortality in people with late-stage RHD (RR 1.23, 95% CI 0.78 to 1.94; 1 study, 994 participants; low-certainty evidence). Antibiotics may not affect the risk of anaphylaxis (Peto odds ratio (OR) 7.39, 95% CI 0.15 to 372; 1 study, 818 participants; low-certainty evidence) or sciatic nerve injury (Peto OR 7.39, 95% CI 0.15 to 372; 1 study, 818 participants; low-certainty evidence) compared with no antibiotics, but probably have an increased risk of hypersensitivity reactions (RR 137, 8.51 to 2210; 2 studies, 894 participants; moderate-certainty evidence) and local reactions (RR 29, 1.74 to 485; 1 study, 818 participants; moderate-certainty evidence). Comparison two: intramuscular antibiotics versus oral antibiotics Pooled analysis of two RCTs showed that prophylactic intramuscular benzathine benzylpenicillin likely reduces recurrence of rheumatic fever substantially when compared to oral antibiotics (0.1% versus 1%, respectively) (RR 0.07, 95% CI 0.02 to 0.26; 395 participants; moderate-certainty evidence). Furthermore, it is unclear whether intramuscular benzyl penicillin is superior to oral antibiotics in reducing the risk of mortality in the context of RHD (Peto OR 0.22, 95% CI 0.01 to 4.12; 1 study, 431 participants; very low-certainty evidence). There were no data available on progression of latent RHD or adverse events including anaphylaxis, sciatic nerve injury, delayed hypersensitivity/allergic reactions and local reactions to injection.

AUTHORS' CONCLUSIONS

This review provides evidence that antibiotic prophylaxis likely reduces the risk of recurrence of rheumatic fever compared to no antibiotics, and that intramuscular benzathine benzylpenicillin is probably superior to oral antibiotics (approximately 10 times better). Moreover, intramuscular benzathine benzylpenicillin likely reduces the risk of progression of latent RHD. Evidence is scarce, but antibiotics compared with no antibiotics may not affect the risk of anaphylaxis or sciatic nerve injury, but probably carry an increased risk of hypersensitivity reactions and local reactions. Antibiotics may not affect all-cause mortality in late-stage RHD compared to no antibiotics. There is no evidence available to comment on the effect of intramuscular penicillin over oral antibiotics for progression of latent RHD and adverse events, and little evidence for all-cause mortality. It is important to interpret these findings in the context of major limitations, including the following: the vast majority of the included studies were conducted more than 50 years ago, many before contemporary echocardiographic studies; methodology was often at high risk of bias; outdated treatments were used; only one study was in latent RHD; and there are concerns regarding generalisability to low socioeconomic regions. This underlines the need for ongoing research to understand who benefits most from prophylaxis.

Cost and cost-effectiveness of treatments for rheumatic heart disease in low- and middle-income countries: a systematic review protocol

OBJECTIVE

This review will synthesize studies on costs, the impact of these costs, and the cost-effectiveness of treatments for rheumatic heart disease (RHD) in low- and middle-income countries.

INTRODUCTION

RHD incurs high costs owing to its clinical complexity, surgical treatments, and prolonged hospital stays. Thus, the disease has a substantial economic impact on the health system, patients, and their families. No systematic review on economic evidence of treatments for RHD has been published to date.

INCLUSION CRITERIA

This review will consider all cost and cost-effectiveness studies on RHD treatments for children and young adults (5─30 years) residing in low- and middle-income countries.

METHODS

The review will follow the JBI methodology for systematic reviews of economic evaluation evidence. The search strategy will locate published and unpublished studies in English. Systematic searches will be conducted in MEDLINE (PubMed), MEDLINE (Ovid), Embase (Ovid), Scopus, CINAHL (EBSCOhost), National Health Service Economic Evaluation Databases, Pediatric Economic Database Evaluation, and Cost-Effectiveness Analysis Registry. Two independent reviewers will screen titles and abstracts, followed by a full-text review based on the inclusion criteria. Data will be extracted using a modified JBI data extraction form for economic evaluations. JBI's Dominance Ranking Matrix for economic evaluations will be used to summarize and compare the results of cost and cost-effectiveness studies. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach will be used to assess the certainty of economic evidence for outcomes related to resource use.

REVIEW REGISTRATION

PROSPERO CRD42023425850.

Handheld echocardiography for the screening and diagnosis of rheumatic heart disease: a systematic review to inform WHO guidelines

BACKGROUND

Early detection and diagnosis of acute rheumatic fever and rheumatic heart disease are key to preventing progression, and echocardiography has an important diagnostic role. Standard echocardiography might not be feasible in high-prevalence regions due to its high cost, complexity, and time requirement. Handheld echocardiography might be an easy-to-use, low-cost alternative, but its performance in screening for and diagnosing acute rheumatic fever and rheumatic heart disease needs further investigation.

METHODS

In this systematic review and meta-analysis, we searched Embase, MEDLINE, LILACS, and Conference Proceedings Citation Index-Science up to Feb 9, 2024, for studies on the screening and diagnosis of acute rheumatic fever and rheumatic heart disease using handheld echocardiography (index test) or standard echocardiography or auscultation (reference tests) in high-prevalence areas. We included all studies with useable data in which the diagnostic performance of the index test was assessed against a reference test. Data on test accuracy in diagnosing rheumatic heart disease, acute rheumatic fever, or carditis with acute rheumatic fever (primary outcomes) were extracted from published articles or calculated, with authors contacted as necessary. Quality of evidence was appraised using GRADE and QUADAS-2 criteria. We summarised diagnostic accuracy statistics (including sensitivity and specificity) and estimated 95% CIs using a bivariate random-effects model (or univariate random-effects models for analyses including three or fewer studies). Area under the curve (AUC) was calculated from summary receiver operating characteristic curves. Heterogeneity was assessed by visual inspection of plots. This study was registered with PROSPERO (CRD42022344081).

FINDINGS

Out of 4868 records we identified 11 studies, and two additional reports, comprising 15 578 unique participants. Pooled data showed that handheld echocardiography had high sensitivity (0·87 [95% CI 0·76-0·93]), specificity (0·98 [0·71-1·00]), and overall high accuracy (AUC 0·94 [0·84-1·00]) for diagnosing rheumatic heart disease when compared with standard echocardiography (two studies; moderate certainty of evidence), with better performance for diagnosing definite compared with borderline rheumatic heart disease. High sensitivity (0·79 [0·73-0·84]), specificity (0·85 [0·80-0·89]), and overall accuracy (AUC 0·90 [0·85-0·94]) for screening rheumatic heart disease was observed when pooling data of handheld echocardiography versus standard echocardiography (seven studies; high certainty of evidence). Most studies had a low risk of bias overall. Some heterogeneity was observed for sensitivity and specificity across studies, possibly driven by differences in the prevalence and severity of rheumatic heart disease, and level of training or expertise of non-expert operators.

INTERPRETATION

Handheld echocardiography has a high accuracy and diagnostic performance when compared with standard echocardiography for diagnosing and screening of rheumatic heart disease in high-prevalence areas.

FUNDING

World Health Organization.

TRANSLATIONS

For the Chinese, French, Italian, Persian, Portuguese, Spanish and Urdu translations of the abstract see Supplementary Materials section.

2023 World Heart Federation guidelines for the echocardiographic diagnosis of rheumatic heart disease

Rheumatic heart disease (RHD) is an important and preventable cause of morbidity and mortality among children and young adults in low-income and middle-income countries, as well as among certain at-risk populations living in high-income countries. The 2012 World Heart Federation echocardiographic criteria provided a standardized approach for the identification of RHD and facilitated an improvement in early case detection. The 2012 criteria were used to define disease burden in numerous epidemiological studies, but researchers and clinicians have since highlighted limitations that have prompted a revision. In this updated version of the guidelines, we incorporate evidence from a scoping review, an expert panel and end-user feedback and present an approach for active case finding for RHD, including the use of screening and confirmatory criteria. These guidelines also introduce a new stage-based classification for RHD to identify the risk of disease progression. They describe the latest evidence and recommendations on population-based echocardiographic active case finding and risk stratification. Secondary antibiotic prophylaxis, echocardiography equipment and task sharing for RHD active case finding are also discussed. These World Heart Federation 2023 guidelines provide a concise and updated resource for clinical and research applications in RHD-endemic regions.

The potential global cost-effectiveness of prospective Strep A vaccines and associated implementation efforts

Group A Streptococcus causes a wide range of diseases from relatively mild infections including pharyngitis to more severe illnesses such as invasive diseases and rheumatic heart disease (RHD). Our aim is to estimate the cost-effectiveness of a hypothetical Strep A vaccine on multiple disease manifestations at the global-level. Cost-effectiveness analyses were carried out by building on the potential epidemiological impact of vaccines that align with the WHO's Preferred Product Characteristics for Strep A vaccines. Maximum vaccination costs for a cost-effective vaccination strategy were estimated at the thresholds of 1XGDP per capita and health opportunity costs. The maximum cost per fully vaccinated person for Strep A vaccination to be cost-effective was $385-$489 in high-income countries, $213-$312 in upper-income-income countries, $74-$132 in lower-middle-income countries, and $37-$69 in low-income countries for routine vaccination at birth and 5 years of age respectively. While the threshold costs are sensitive to vaccine characteristics such as efficacy, and waning immunity, a cost-effective Strep A vaccine will lower morbidity and mortality burden in all income settings.

Modalities of group A streptococcal prevention and treatment and their economic justification

Infection by group A Streptococcus (Strep A) results in a diverse range of clinical conditions, including pharyngitis, impetigo, cellulitis, necrotising fasciitis, and rheumatic heart disease. In this article, we outline the recommended strategies for Strep A treatment and prevention and review the literature for economic evaluations of competing treatment and prevention strategies. We find that most economic evaluations focus on reducing the duration of illness or risk of rheumatic fever among people presenting with sore throat through diagnostic and/or treatment strategies. Few studies have evaluated strategies to reduce the burden of Strep A infection among the general population, nor have they considered the local capacity to finance and implement strategies. Evaluation of validated costs and consequences for a more diverse range of Strep A interventions are needed to ensure policies maximise patient outcomes under budget constraints. This should include attention to basic public health strategies and emerging strategies such as vaccination.

Evaluating efficiency and equity of prevention and control strategies for rheumatic fever and rheumatic heart disease in India: an extended cost-effectiveness analysis

BACKGROUND

There is a dearth of evidence on the cost-effectiveness of a combination of population-based primary, secondary, and tertiary prevention and control strategies for rheumatic fever and rheumatic heart disease. The present analysis evaluated the cost-effectiveness and distributional effect of primary, secondary, and tertiary interventions and their combinations for the prevention and control of rheumatic fever and rheumatic heart disease in India.

METHODS

A Markov model was constructed to estimate the lifetime costs and consequences among a hypothetical cohort of 5-year-old healthy children. Both health system costs and out-of-pocket expenditure (OOPE) were included. OOPE and health-related quality-of-life were assessed by interviewing 702 patients enrolled in a population-based rheumatic fever and rheumatic heart disease registry in India. Health consequences were measured in terms of life-years and quality-adjusted life-years (QALY) gained. Furthermore, an extended cost-effectiveness analysis was undertaken to assess the costs and outcomes across different wealth quartiles. All future costs and consequences were discounted at an annual rate of 3%.

FINDINGS

A combination of secondary and tertiary prevention strategies, which had an incremental cost of ₹23 051 (US$30) per QALY gained, was the most cost-effective strategy for the prevention and control of rheumatic fever and rheumatic heart disease in India. The number of rheumatic heart disease cases prevented among the population belonging to the poorest quartile (four cases per 1000) was four times higher than the richest quartile (one per 1000). Similarly, the reduction in OOPE after the intervention was higher among the poorest income group (29·8%) than among the richest income group (27·0%).

INTERPRETATION

The combined secondary and tertiary prevention and control strategy is the most cost-effective option for the management of rheumatic fever and rheumatic heart disease in India, and the benefits of public spending are likely to be accrued much more by those in the lowest income groups. The quantification of non-health gains provides strong evidence for informing policy decisions by efficient resource allocation on rheumatic fever and rheumatic heart disease prevention and control in India.

FUNDING

Department of Health Research, Ministry of Health and Family Welfare, New Delhi.

Recent Advances in the Rheumatic Fever and Rheumatic Heart Disease Continuum

Nearly a century after rheumatic fever (RF) and rheumatic heart disease (RHD) was eradicated from the developed world, the disease remains endemic in many low- and middle-income countries (LMICs), with grim health and socioeconomic impacts. The neglect of RHD which persisted for a semi-centennial was further driven by competing infectious diseases, particularly the human immunodeficiency virus (HIV) pandemic. However, over the last two-decades, slowly at first but with building momentum, there has been a resurgence of interest in RF/RHD. In this narrative review, we present the advances that have been made in the RF/RHD continuum over the past two decades since the re-awakening of interest, with a more concise focus on the last decade's achievements. Such primary advances include understanding the genetic predisposition to RHD, group A Streptococcus (GAS) vaccine development, and improved diagnostic strategies for GAS pharyngitis. Echocardiographic screening for RHD has been a major advance which has unearthed the prevailing high burden of RHD and the recent demonstration of benefit of secondary antibiotic prophylaxis on halting progression of latent RHD is a major step forward. Multiple befitting advances in tertiary management of RHD have also been realized. Finally, we summarize the research gaps and provide illumination on profitable future directions towards global eradication of RHD.

Existing cost-effectiveness analyses for diseases caused by Group A Streptococcus: A systematic review to guide future research

Background: Group A Streptococcus (Strep A) causes a broad spectrum of disease manifestations, ranging from benign symptoms including throat or skin infections, to fatal illness such as rheumatic heart disease, or chronic renal failure. Currently, there is no vaccine available against Strep A infections. Despite the high burden of Strep A-associated infections worldwide, little attention has been paid to the research of these diseases, including standardized surveillance programs, resulting in a lack of economic evaluations for prevention efforts. This study aims at identifying existing cost-effectiveness analyses (CEA) on any Strep A infections. Methods: A systematic literature review was conducted by searching the PubMed electronic database. Results: Of a total of 321, 44 articles met the criteria for inclusion. Overall, CEA studies on Strep A remain limited in number. In particular, a number of available CEA studies on Strep A are disproportionately lower in low-income countries than in high-income countries. Decision-analytic models were the most popular choice for CEA on Strep A. A majority of the models considered pharyngitis and acute rheumatic fever, but it was rare to observe a model which covered a wide range of disease manifestations. Conclusions: Future research is needed to address missing clinical outcomes, imbalance on study locations by income group, and the transmission dynamic of selected diseases.

Detection of subclinical rheumatic heart disease in children using a deep learning algorithm on digital stethoscope: a study protocol

INTRODUCTION

Rheumatic heart diseases (RHDs) contribute significant morbidity and mortality globally. To reduce the burden of RHD, timely initiation of secondary prophylaxis is important. The objectives of this study are to determine the frequency of subclinical RHD and to train a deep learning (DL) algorithm using waveform data from the digital auscultatory stethoscope (DAS) in predicting subclinical RHD.

METHODS AND ANALYSIS

We aim to recruit 1700 children from a group of schools serving the underprivileged over a 12-month period in Karachi (Pakistan). All consenting students within the age of 5-15 years with no underlying congenital heart disease will be eligible for the study. We will gather information regarding sociodemographics, anthropometric data, history of symptoms or diagnosis of rheumatic fever, phonocardiogram (PCG) and electrocardiography (ECG) data obtained from DAS. Handheld echocardiogram will be performed on each study participant to assess the presence of a mitral regurgitation (MR) jet (>1.5 cm), or the presence of aortic regurgitation (AR) in any view. If any of these findings are present, a confirmatory standard echocardiogram using the World Heart Federation (WHF) will be performed to confirm the diagnosis of subclinical RHD. The auscultatory data from digital stethoscope will be used to train the deep neural network for the automatic identification of patients with subclinical RHD. The proposed neural network will be trained in a supervised manner using labels from standard echocardiogram of the participants. Once trained, the neural network will be able to automatically classify the DAS data in one of the three major categories-patient with definite RHD, patient with borderline RHD and normal subject. The significance of the results will be confirmed by standard statistical methods for hypothesis testing.

ETHICS AND DISSEMINATION

Ethics approval has been taken from the Aga Khan University, Pakistan. Findings will be disseminated through scientific publications and to collaborators.

ARTICLE FOCUS

This study focuses on determining the frequency of subclinical RHD in school-going children in Karachi, Pakistan and developing a DL algorithm to screen for this condition using a digital stethoscope.

An investment case for the prevention and management of rheumatic heart disease in the African Union 2021-30: a modelling study

BACKGROUND

Despite declines in deaths from rheumatic heart disease (RHD) in Africa over the past 30 years, it remains a major cause of cardiovascular morbidity and mortality on the continent. We present an investment case for interventions to prevent and manage RHD in the African Union (AU).

METHODS

We created a cohort state-transition model to estimate key outcomes in the disease process, including cases of pharyngitis from group A streptococcus, episodes of acute rheumatic fever (ARF), cases of RHD, heart failure, and deaths. With this model, we estimated the impact of scaling up interventions using estimates of effect sizes from published studies. We estimated the cost to scale up coverage of interventions and summarised the benefits by monetising health gains estimated in the model using a full income approach. Costs and benefits were compared using the benefit-cost ratio and the net benefits with discounted costs and benefits.

FINDINGS

Operationally achievable levels of scale-up of interventions along the disease spectrum, including primary prevention, secondary prevention, platforms for management of heart failure, and heart valve surgery could avert 74 000 (UI 50 000-104 000) deaths from RHD and ARF from 2021 to 2030 in the AU, reaching a 30·7% (21·6-39·0) reduction in the age-standardised death rate from RHD in 2030, compared with no increase in coverage of interventions. The estimated benefit-cost ratio for plausible scale-up of secondary prevention and secondary and tertiary care interventions was 4·7 (2·9-6·3) with a net benefit of $2·8 billion (1·6-3·9; 2019 US$) through 2030. The estimated benefit-cost ratio for primary prevention scale-up was low to 2030 (0·2, <0·1-0·4), increasing with delayed benefits accrued to 2090. The benefit-cost dynamics of primary prevention were sensitive to the costs of different delivery approaches, uncertain epidemiological parameters regarding group A streptococcal pharyngitis and ARF, assumptions about long-term demographic and economic trends, and discounting.

INTERPRETATION

Increased coverage of interventions to control and manage RHD could accelerate progress towards eradication in AU member states. Gaps in local epidemiological data and particular components of the disease process create uncertainty around the level of benefits. In the short term, costs of secondary prevention and secondary and tertiary care for RHD are lower than for primary prevention, and benefits accrue earlier.

FUNDING

World Heart Federation, Leona M and Harry B Helmsley Charitable Trust, and American Heart Association.

Secondary prophylaxis to control rheumatic heart disease in developing countries: Put into a cage if can't be killed

A significant socioeconomic inequality is the main barrier to achieve primordial prevention of rheumatic heart disease (RHD) in the developing countries. An effective vaccine with affordable cost against Streptococcus yet to be identified. The subclinical nature of rheumatic fever (RF) is the main hurdle for effective primary prevention of RHD. When RF and RHD are recognized at the earliest, treated adequately and SP with penicillin is strictly followed, then this disease can be kept under control though cannot be eradicated.

The WHF Roadmap for Reducing CV Morbidity and Mortality Through Prevention and Control of RHD

Rheumatic heart disease (RHD) is a preventable non-communicable condition that disproportionately affects the world's poorest and most vulnerable. The World Heart Federation Roadmap for improved RHD control is a resource designed to help a variety of stakeholders raise the profile of RHD nationally and globally, and provide a framework to guide and support the strengthening of national, regional and global RHD control efforts. The Roadmap identifies the barriers that limit access to and uptake of proven interventions for the prevention and control of RHD. It also highlights a variety of established and promising solutions that may be used to overcome these barriers. As a general guide, the Roadmap is meant to serve as the foundation for the development of tailored plans of action to improve RHD control in specific contexts.

Rheumatic Heart Disease Severity, Progression and Outcomes: A Multi-State Model

Background

Rheumatic heart disease (RHD) remains a disease of international importance, yet little has been published about disease progression in a contemporary patient cohort. Multi‐state models provide a well‐established method of estimating rates of transition between disease states, and can be used to evaluate the cost‐effectiveness of potential interventions. We aimed to create a multi‐state model for RHD progression using serial clinical data from a cohort of Australian patients.

Methods and Results

The Northern Territory RHD register was used to identify all Indigenous residents diagnosed with RHD between the ages of 5 and 24 years in the time period 1999–2012. Disease severity over time, surgeries, and deaths were evaluated for 591 patients. Of 96 (16.2%) patients with severe RHD at diagnosis, 50% had proceeded to valve surgery by 2 years, and 10% were dead within 6 years. Of those diagnosed with moderate RHD, there was a similar chance of disease regression or progression over time. Patients with mild RHD at diagnosis were the most stable, with 64% remaining mild after 10 years; however, 11.4% progressed to severe RHD and half of these required surgery.

Conclusions

The prognosis of young Indigenous Australians diagnosed with severe RHD is bleak; interventions must focus on earlier detection and treatment if the observed natural history is to be improved. This multi‐state model can be used to predict the effect of different interventions on disease progression and the associated costs.

Echocardiographic Screening for Rheumatic Heart Disease in Indigenous Australian Children: A Cost-Utility Analysis

BACKGROUND

Rheumatic heart disease (RHD) remains a leading cause of cardiovascular morbidity and mortality in children and young adults in disadvantaged populations. The emergence of echocardiographic screening provides the opportunity for early disease detection and intervention. Using our own multistate model of RHD progression derived from Australian RHD register data, we performed a cost-utility analysis of echocardiographic screening in indigenous Australian children, with the dual aims of informing policy decisions in Australia and providing a model that could be adapted in other countries.

METHODS AND RESULTS

We simulated the outcomes of 2 screening strategies, assuming that RHD could be detected 1, 2, or 3 years earlier by screening. Outcomes included reductions in heart failure, surgery, mortality, disability-adjusted life-years, and corresponding costs. Only a strategy of screening all indigenous 5- to 12-year-olds in half of their communities in alternate years was found to be cost-effective (incremental cost-effectiveness ratio less than AU$50 000 per disability-adjusted life-year averted), assuming that RHD can be detected at least 2 years earlier by screening; however, this result was sensitive to a number of assumptions. Additional modeling of improved adherence to secondary prophylaxis alone resulted in dramatic reductions in heart failure, surgery, and death; these outcomes improved even further when combined with screening.

CONCLUSIONS

Echocardiographic screening for RHD is cost-effective in our context, assuming that RHD can be detected ≥2 years earlier by screening. Our model can be adapted to any other setting but will require local data or acceptable assumptions for model parameters.

Child and teacher acceptability of school-based echocardiographic screening for rheumatic heart disease in Uganda

Introduction Rheumatic heart disease causes substantial morbidity in children in low-income countries. School-based echocardiographic screening has been suggested as a means to identify children with latent disease; however, little is known about the experience of children and teachers participating in screenings. The aim of our study was to assess students' and teachers' experience of school-based echocardiographic screening and identify areas for improvement. Materials and methods A school-based echocardiographic screening programme was conducted in five schools in Northern Uganda in 2013. After 8 months, an age- and gender-stratified population that included 5% of the participating students and teachers completed a questionnaire via an in-person interview. Responses were reviewed by question and coded to identify key themes.

RESULTS

A total of 255 students (mean 10.7 years; 48% male) and 35 teachers participated in our study. In total, 95% of the students and 100% of the teachers were happy to have participated in the screening; however, students reported feeling scared (35%) and nervous (48%) during the screening process. Programmatic strengths included the following: knowing one's health status, opportunity to receive treatment, and staff interactions. Although 43% of the patients did not suggest a change with open-ended questioning, concerns regarding privacy, fear of the screening process, and a desire to include others in the community were noted. Discussion School-based echocardiographic rheumatic heart disease screening was well received by students and teachers. Future programmes would likely benefit from improved pre-screening education regarding the screening process and diagnosis of rheumatic heart disease. Furthermore, education of teachers and students could improve screening perception and establish realistic expectations regarding the scope of screening.

Rheumatic heart disease screening: Current concepts and challenges

Rheumatic heart disease (RHD) is a disease of poverty, is almost entirely preventable, and is the most common cardiovascular disease worldwide in those under 25 years. RHD is caused by acute rheumatic fever (ARF) which typically results in cumulative valvular lesions that may present clinically after a number of years of subclinical disease. Therapeutic interventions, therefore, typically focus on preventing subsequent ARF episodes (with penicillin prophylaxis). However, not all patients with ARF develop symptoms and not all symptomatic cases present to a physician or are correctly diagnosed. Therefore, if we hope to control ARF and RHD at the population level, we need a more reliable discriminator of subclinical disease. Recent studies have examined the utility of echocardiographic screening, which is far superior to auscultation at detecting RHD. However, there are many concerns surrounding this approach. Despite the introduction of the World Heart Federation diagnostic criteria in 2012, we still do not really know what constitutes the most subtle changes of RHD by echocardiography. This poses serious problems regarding whom to treat and what to do with the rest, both important decisions with widespread implications for already stretched health-care systems. In addition, issues ranging from improving the uptake of penicillin prophylaxis in ARF/RHD-positive patients, improving portable echocardiographic equipment, understanding the natural history of subclinical RHD and how it might respond to penicillin, and developing simplified diagnostic criteria that can be applied by nonexperts, all need to be effectively tackled before routine widespread screening for RHD can be endorsed.

A Cost-Effectiveness Tool to Guide the Prioritization of Interventions for Rheumatic Fever and Rheumatic Heart Disease Control in African Nations

BACKGROUND

Rheumatic heart disease (RHD) prevalence and mortality rates remain especially high in many parts of Africa. While effective prevention and treatment exist, coverage rates of the various interventions are low. Little is known about the comparative cost-effectiveness of different RHD interventions in limited resource settings. We developed an economic evaluation tool to assist ministries of health in allocating resources and planning RHD control programs.

METHODOLOGY/PRINCIPAL FINDINGS

We constructed a Markov model of the natural history of acute rheumatic fever (ARF) and RHD, taking transition probabilities and intervention effectiveness data from previously published studies and expert opinion. Our model estimates the incremental cost-effectiveness of scaling up coverage of primary prevention (PP), secondary prevention (SP) and heart valve surgery (VS) interventions for RHD. We take a healthcare system perspective on costs and measure outcomes as disability-adjusted life-years (DALYs), discounting both at 3%. Univariate and probabilistic sensitivity analyses are also built into the modeling tool. We illustrate the use of this model in a hypothetical low-income African country, drawing on available disease burden and cost data. We found that, in our hypothetical country, PP would be cost saving and SP would be very cost-effective. International referral for VS (e.g., to a country like India that has existing surgical capacity) would be cost-effective, but building in-country VS services would not be cost-effective at typical low-income country thresholds.

CONCLUSIONS/SIGNIFICANCE

Our cost-effectiveness analysis tool is designed to inform priorities for ARF/RHD control programs in Africa at the national or subnational level. In contrast to previous literature, our preliminary findings suggest PP could be the most efficient and cheapest approach in poor countries. We provide our model for public use in the form of a Supplementary File. Our research has immediate policy relevance and calls for renewed efforts to scale up RHD prevention.

Rheumatic heart disease echocardiographic screening: approaching practical and affordable solutions

Rheumatic heart disease (RHD) affects at least 32.9 million people worldwide and ranks as a leading cause of death and disability in low-income and middle-income countries (LMICs). Echocardiographic screening has been demonstrated to be a powerful tool for early RHD detection, and holds potential for global RHD control. However, national screening programmes have not emerged. Major barriers to implementation include the lack of human and financial resources in LMICs. Here, we focus on recent research advances that could make echocardiographic screening more practical and affordable, including handheld echocardiography devices, simplified screening protocols and task shifting of echocardiographic screening to non-experts. Additionally, we highlight some important remaining questions before echocardiographic screening can be widely recommended, including demonstration of cost-effectiveness, assessment of the impact of screening on children and communities, and determining the importance of latent RHD. While a single strategy for echocardiographic screening in all high-prevalence areas is unlikely, we believe recent advancements are bringing the public health community closer to developing sustainable programmes for echocardiographic screening.

Acute rheumatic fever and rheumatic heart disease

Acute rheumatic fever (ARF) is the result of an autoimmune response to pharyngitis caused by infection with group A Streptococcus. The long-term damage to cardiac valves caused by ARF, which can result from a single severe episode or from multiple recurrent episodes of the illness, is known as rheumatic heart disease (RHD) and is a notable cause of morbidity and mortality in resource-poor settings around the world. Although our understanding of disease pathogenesis has advanced in recent years, this has not led to dramatic improvements in diagnostic approaches, which are still reliant on clinical features using the Jones Criteria, or treatment practices. Indeed, penicillin has been the mainstay of treatment for decades and there is no other treatment that has been proven to alter the likelihood or the severity of RHD after an episode of ARF. Recent advances - including the use of echocardiographic diagnosis in those with ARF and in screening for early detection of RHD, progress in developing group A streptococcal vaccines and an increased focus on the lived experience of those with RHD and the need to improve quality of life - give cause for optimism that progress will be made in coming years against this neglected disease that affects populations around the world, but is a particular issue for those living in poverty.

Rheumatic heart disease among adults in a mining community of Papua, Indonesia: findings from an occupational cohort

Background

Rheumatic heart disease (RHD) remains a significant cause of cardiovascular morbidity and mortality in developing countries such as Indonesia. Yet, despite being one of the most readily preventable chronic diseases, RHD has received scant research or policy attention, particularly in South-East Asia.

Aim

To describe the pattern of RHD occurrence in a sample of presenting cases from an occupational cohort in Papua Province, Indonesia.

Methods

Clinical records of 15 608 mining workers (96.4% men, mean age 36.3±7.4 years) were reviewed retrospectively to identify and extract data on all rheumatic fever (RF) and RHD cases admitted to two hospitals in Papua during 2008–2013. Collected data included basic demographics, employment history and echocardiographic findings.

Results

83 RHD cases (95.6% men, mean age 39.6±12.5 years) and 3 RF cases were identified between 2008 and 2013. Increased RHD risk was observed among those aged 35–44 (HR=3.60) and 45–68 (HR=4.46) years relative to the youngest age group (p<0.01). RHD incidence density was 6.84 per 10 000 person years of follow-up. Among cases, mitral stenosis was the most common valvular lesion at initial presentation (41.0%), and 6.0% were multivalvular.

Conclusions

The prevalence of RHD in Papuan mining workers correlates with adult prevalence data in other populations with a high RHD burden, highlighting RHD as a significant health issue into adulthood. The late stage at which most patients presented points to a strong need for earlier intervention. Both primary and secondary preventive measures must be considered critical tools to prevent and reduce RHD burden, particularly among older age groups.

Echo-based screening of rheumatic heart disease in children: a cost-effectiveness Markov model

OBJECTIVES

To project the cost-effectiveness of population-based echo screening to prevent rheumatic heart disease (RHD) consequences.

BACKGROUND

RHD is a leading cause of cardiovascular mortality and morbidity during adolescence and young adulthood in low- and middle-per capita income settings. Echocardiography-based screening approaches can dramatically expand the number of children identified at risk of progressive RHD. Cost-effectiveness analysis can inform public health agencies and payers about the net economic benefit of such large-scale population-based screening.

METHODS

A Markov model was constructed comparing a no-screen to echo screen approach. The echo screen program was modeled as a 2-staged screen of a cohort of 11-year-old children with initial short screening performed by dedicated technicians and follow-up complete echo by cardiologists. Penicillin RHD prophylaxis was modeled to only reduce rheumatic fever recurrence-related exacerbation. Quality-adjusted life years (QALYs) and societal costs (in 2010 Australian dollars) associated with each approach were estimated. One-way, two-way and probabilistic sensitivity analyses were performed on RHD prevalence and transition probabilities; echocardiography test characteristics; and societal level costs including supplies, transportation, and labor.

RESULTS

The incremental costs and QALYs of the screen compared to no screen strategy were -$432 (95% CI = -$1357 to $575) and 0.007 (95% CI = -0.0101 to 0.0237), respectively. The joint probability that the screen was both less costly and more effective exceeded 80%. Sensitivity analyses suggested screen strategy dominance depends mostly on the probability of transitioning out of sub-clinical RHD.

CONCLUSION

Two-stage echo RHD screening and secondary prophylaxis may achieve modestly improved outcomes at lower cost compared to clinical detection and deserves closer attention from health policy stakeholders.

A cost-effectiveness analysis of a program to control rheumatic fever and rheumatic heart disease in Pinar del Rio, Cuba

Background

Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) persist in many low- and middle-income countries. To date, the cost-effectiveness of population-based, combined primary and secondary prevention strategies has not been assessed. In the Pinar del Rio province of Cuba, a comprehensive ARF/RHD control program was undertaken over 1986 – 1996. The present study analyzes the cost-effectiveness of this Cuban program.

Methods and Findings

We developed a decision tree model based on the natural history of ARF/RHD, comparing the costs and effectiveness of the 10-year Cuban program to a “do nothing” approach. Our population of interest was the cohort of children aged 5 – 24 years resident in Pinar del Rio in 1986. We assessed costs and health outcomes over a lifetime horizon, and we took the healthcare system perspective on costs but did not apply a discount rate. We used epidemiologic, clinical, and direct medical cost inputs that were previously collected for publications on the Cuban program. We estimated health gains as disability-adjusted life years (DALYs) averted using standard approaches developed for the Global Burden of Disease studies. Cost-effectiveness acceptability thresholds were defined by one and three times per capita gross domestic product per DALY averted. We also conducted an uncertainty analysis using Monte Carlo simulations and several scenario analyses exploring the impact of alternative assumptions about the program’s effects and costs. We found that, compared to doing nothing, the Cuban program averted 5051 DALYs (1844 per 100,000 school-aged children) and saved $7,848,590 (2010 USD) despite a total program cost of $202,890 over 10 years. In the scenario analyses, the program remained cost saving when a lower level of effectiveness and a reduction in averted years of life lost were assumed. In a worst-case scenario including 20-fold higher costs, the program still had a 100% of being cost-effective and an 85% chance of being cost saving.

Conclusions

A 10-year program to control ARF/RHD in Pinar del Rio, Cuba dramatically reduced morbidity and premature mortality in children and young adults and was cost saving. The results of our analysis were robust to higher program costs and more conservative assumptions about the program’s effectiveness. It is possible that the program’s effectiveness resulted from synergies between primary and secondary prevention strategies. The findings of this study have implications for non-communicable disease policymaking in other resource-limited settings.

Screening for rheumatic heart disease: evaluation of a focused cardiac ultrasound approach

BACKGROUND

Rheumatic heart disease (RHD) remains a major public health problem worldwide. Although early diagnosis by echocardiography may potentially play a key role in developing active surveillance, systematic evaluation of simple approaches in resource poor settings are needed.

METHODS AND RESULTS

We prospectively compared focused cardiac ultrasound (FCU) to a reference approach for RHD screening in a school children population. FCU included (1) the use of a pocket-sized echocardiography machine, (2) nonexpert staff (2 nurses with specific training), and (3) a simplified set of echocardiographic criteria. The reference approach used standardized echocardiographic examination, reviewed by an expert cardiologist, according to 2012 World Heart Federation criteria. Among the 6 different echocardiographic criteria, first tested in a preliminary phase, mitral regurgitation jet length≥2 cm or any aortic regurgitation was considered best suited to be FCU criteria. Of the 1217 subjects enrolled (mean, 9.6±1 years; 49.6% male), 49 (4%) were diagnosed with RHD by the reference approach. The sensitivity of FCU for the detection of RHD was 83.7% (95% confidence interval, 73.3-94.0) for nurse A and 77.6% (95% confidence interval, 65.9-89.2) for nurse B. FCU yielded a specificity of 90.9% (95% confidence interval, 89.3-92.6) and 92.0% (95% confidence interval, 90.4-93.5) according to users. Percentage of agreement among nurses was 91.4%.

CONCLUSIONS

FCU by nonexperts using pocket devices seems feasible and yields acceptable sensitivity and specificity for RHD detection when compared with the state-of-the-art approach, thereby opening new perspectives for mass screening for RHD in low-resource settings.

Controlling acute rheumatic fever and rheumatic heart disease in developing countries: are we getting closer?

PURPOSE OF REVIEW

To describe new developments (2013-2014) in acute rheumatic fever (ARF) and rheumatic heart disease (RHD) relevant to developing countries.

RECENT FINDINGS

Improved opportunities for the primary prevention of ARF now exist, because of point-of-care antigen tests for Streptococcus pyogenes, and clinical decision rules which inform management of pharyngitis without requiring culture results. There is optimism that a vaccine, providing protection against many ARF-causing S. pyogenes strains, may be available in coming years. Collaborative approaches to RHD control, including World Heart Federation initiatives and the development of registers, offer promise for better control of this disease. New data on RHD-associated costs provide persuasive arguments for better government-level investment in primary and secondary prevention. There is expanding knowledge of potential biomarkers and immunological profiles which characterize ARF/RHD, and genetic mutations conferring ARF/RHD risk, but as yet no new diagnostic testing strategy is ready for clinical application.

SUMMARY

Reduction in the disease burden and national costs of ARF and RHD are major priorities. New initiatives in the primary and secondary prevention of ARF/RHD, novel developments in pathogenesis and biomarker research and steady progress in vaccine development, are all causes for optimism for improving control of ARF/RHD, which affect the poorest of the poor.

Rheumatic heart disease in Tennessee: An overlooked diagnosis

Rheumatic heart disease, already a major burden in low- and middle-income countries, is becoming an emerging problem in high-income countries. Although acute rheumatic fever and rheumatic heart disease have almost been eradicated in areas with established economies, the emergence of this problem may be attributable to the migration from low-income to high-income settings. Between 2010 and 2012, we diagnosed a cluster of rheumatic heart disease cases in children from the Middle Tennessee area. The goal of this report is to increase awareness among clinicians as the incidence and prevalence of acute rheumatic fever remain relatively significant in large US metropolitan areas. Although acute rheumatic fever is seasonal, a high suspicion index may lead to the early diagnosis and prevention of its cardiac complications. Furthermore, screening procedures may be recommended for populations at risk for rheumatic heart disease in endemic areas, and active surveillance with echocardiography-based screening might become very important.