Single-View Echocardiography by Nonexpert Practitioners to Detect Rheumatic Heart Disease: A Prospective Study of Diagnostic Accuracy

Assessing the Role of Echocardiography in Pregnancy in First Nations Australian Women: Is it an Underutilised Resource?

BACKGROUND

Rheumatic heart disease (RHD) remains prevalent within First Nations Australian communities. RHD is more common in females and peak prevalence corresponds with childbearing age. Significant valvular disease can complicate pregnancy. Current practice in Northern Australia is to refer pregnant women for echocardiography if there are signs or symptoms of possible cardiac pathology or a history of acute rheumatic fever (ARF) or RHD. It is not currently routine practice to offer echocardiographic screening for all pregnant women at high risk of RHD.

AIM

This study aimed to assess the current referral practices for echocardiography and disease patterns in pregnant women in the Northern Territory, Australia-a region with a known high prevalence of RHD in the First Nations population.

METHOD

A retrospective analysis of all echocardiography referrals of pregnant women over a 4-year period was performed. Data included indication for echocardiography, clinical history, echocardiographic findings, and location of delivery. Comparisons were made using Fisher's exact and Mann-Whitney U tests.

RESULTS

A total of 322 women underwent echocardiography during pregnancy: 195 First Nations and 127 non-Indigenous women (median age, 25 vs 30 years, respectively; p<0.01). Indications for echocardiography differed by ethnicity, with history of ARF or RHD being the most common indication in First Nations women, and incidental murmur the most common in non-Indigenous women. First Nations women were more likely to have abnormal echocardiograms (35.9% vs 11.0% in non-Indigenous women; p<0.01) or a history of ARF or RHD (39.5% vs 0.8%; p<0.01), but less likely to have documented cardiac symptoms as an indication for echocardiography (8.2% vs 20.5%; p<0.01). New cardiac diagnoses were made during pregnancy in 11 (5.6%) First Nations and two (1.6%) non-Indigenous women (p=0.02). Moderate or severe valve lesions were detected in 26 (13.3%) First Nations women (all previously diagnosed), and 11 (5.6%) had previous cardiac surgery. No severe valve lesions were identified in the non-Indigenous group. Interstate transfer to a tertiary centre with valve intervention services was required during pregnancy or the puerperium for 12 (6.2%) First Nations women and no non-Indigenous women.

CONCLUSIONS

Amongst pregnant women in the Northern Territory who had an indication for echocardiography, First Nations women were more likely to have abnormal echocardiograms. This was mainly due to valvular disease secondary to RHD. Cardiac symptoms were infrequently recorded as an indication for echocardiography in First Nations women, suggesting possible underappreciation of symptoms. Having a low threshold for echocardiographic investigation, including consideration of universal screening during pregnancy, is important in a high RHD-burden setting such as ours. A better understanding of the true prevalence and spectrum of disease severity in this population would enable health services to invest in appropriate resources.

Echocardiographic Screening for Rheumatic Heart Disease: A Brief History and Implications for the Future

Transthoracic echocardiography is the gold standard for early detection of rheumatic heart disease (RHD) in asymptomatic children living in high-risk regions. Advances in technology allowing miniaturisation and increased portability of echocardiography devices have improved the accessibility of this vital diagnostic tool in RHD-endemic locations. Automation of image optimisation techniques and simplified RHD screening protocols permit use by non-experts after a brief period of training. While these changes are welcome advances in the battle to manage RHD, it is important that the sensitivity and specificity of RHD detection be maintained by all echocardiography users on any device to ensure accurate and timely diagnosis of RHD to facilitate initiation of appropriate therapy. This review of the evolution of echocardiography and its use in the detection of rheumatic valve disease may serve as a reminder of the key strengths and potential pitfalls of this increasingly relied-upon diagnostic test.

Point-of-care AI-enhanced novice echocardiography for screening heart failure (PANES-HF)

The increasing prevalence of heart failure (HF) in ageing populations drives demand for echocardiography (echo). There is a worldwide shortage of trained sonographers and long waiting times for expert echo. We hypothesised that artificial intelligence (AI)-enhanced point-of-care echo can enable HF screening by novices. The primary endpoint was the accuracy of AI-enhanced novice pathway in detecting reduced LV ejection fraction (LVEF) < 50%. Symptomatic patients with suspected HF (N = 100, mean age 61 ± 15 years, 56% men) were prospectively recruited. Novices with no prior echo experience underwent 2-weeks' training to acquire echo images with AI guidance using the EchoNous Kosmos handheld echo, with AI-automated reporting by Us2.ai (AI-enhanced novice pathway). All patients also had standard echo by trained sonographers interpreted by cardiologists (reference standard). LVEF < 50% by reference standard was present in 27 patients. AI-enhanced novice pathway yielded interpretable results in 96 patients and took a mean of 12 min 51 s per study. The area under the curve (AUC) of the AI novice pathway was 0.880 (95% CI 0.802, 0.958). The sensitivity, specificity, positive predictive and negative predictive values of the AI-enhanced novice pathway in detecting LVEF < 50% were 84.6%, 91.4%, 78.5% and 94.1% respectively. The median absolute deviation of the AI-novice pathway LVEF from the reference standard LVEF was 6.03%. AI-enhanced novice pathway holds potential to task shift echo beyond tertiary centres and improve the HF diagnostic workflow.

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.

Silent Acute Rheumatic Fever Unmasked by Using Handheld Echocardiography for Febrile Children Presenting in a Rheumatic Heart Disease-Endemic Area

OBJECTIVE

To understand the burden of acute rheumatic fever (ARF) among children living in low-income countries who present to the hospital with febrile illness and to determine the role of handheld echocardiography (HHE) in uncovering subclinical carditis as a major manifestation of ARF.

STUDY DESIGN

This was a cross-sectional study carried at the Pediatric Hospital in Al Obeid, North Kordofan, Sudan, from September 2022 to January 2023 and including febrile children 3 through 18 years of age with or without clinical features of ARF and without another cause for their fever (not excluding malaria). History, examination, blood investigations, and HHE were done. ARF was diagnosed according to the Jones criteria. Clinical ARF was diagnosed if there was a major clinical Jones criterion and silent ARF if the only major Jones criteria was subclinical carditis.

RESULTS

The study cohort included 400 children with a mean age of 9 years. Clinical ARF was diagnosed in 95 patients (95/400, 24%), most of whom presented with a joint major manifestation (88/95, 93%). Among the 281 children who did not present with a clinical manifestation of ARF, HHE revealed rheumatic heart disease (RHD) in 44 patients (44/281, 16%); 31 of them fulfilled criteria for silent ARF (31/281, 11%). HHE increased the detection of ARF by 24%. HHE revealed mild RHD in 41 of 66 (62%) and moderate or severe RHD in 25 of 66 (38%) patients. Both sensitivity and specificity of HHE compared with standard echocardiography were 88%.

CONCLUSIONS

There is a significant burden of ARF among febrile children in Sudan. HHE increased the sensitivity of diagnosis, with 11% of children having subclinical carditis as their only major manifestation (ie, silent ARF). RHD-prevention policies need to prioritize decentralization of echocardiography to improve ARF detection.

The Impact of a Handheld Ultrasound Device in a Rheumatic Heart Disease Screening Program in Ethiopia

Background: Rheumatic heart disease (RHD) affects 33 million people in low and middle income countries and is the leading cause of cardiovascular death among children and young adults. Penicillin prophylaxis prevents progression in asymptomatic disease. Efforts to expand echocardiographic screening are focusing on simplified protocols, non-physician ultrasonographers, and portable ultrasound devices, including handheld ultrasound. Recent advances support the use of single-view screening protocols. With the increasing availability and low cost of handheld devices, studies are needed to evaluate their performance in these settings. Methods: We conducted a retrospective study comparing the rate of screen positive ultrasounds before and after the use of a handheld ultrasound in an RHD screening program in Ethiopia. We also performed a cross-sectional device comparison in 19 at-risk school-children participating in the rheumatic heart disease screening program. Results: Between March of 2019 and January of 2022, 6631 children were screened for rheumatic heart disease of whom 4029 were screened after the introduction of a handheld device. Before the use of the handheld ultrasound device 291 (11.2%) children had a screen positive ultrasounds compared with 167 (4.1%) afterwards (p<0.001). We also compared non-expert to expert interpretation by device and found a significant difference in interpretation for the Lumify (p=0.025). There was a trend towards shorter jet length by color Doppler in the handheld ultrasound device for both expert and non-expert review. Conclusions: Our study highlights that the screen-positive rate in a RHD screening program is influenced by the device being used in the screening process.

Abbreviated Echocardiographic Screening for Rheumatic Heart Disease by Nonexperts with and without Offsite Expert Review: A Diagnostic Accuracy Study

BACKGROUND

Early detection of rheumatic heart disease (RHD) through echocardiographic screening can facilitate early access to effective treatment, which reduces the risk for progression. Accurate, feasible approaches to echocardiographic screening that can be incorporated into routine health services are needed. The authors hypothesized that offsite expert review could improve the diagnostic accuracy of nonexpert-obtained echocardiographic images.

METHODS

This prospective cross-sectional study was performed to evaluate the diagnostic accuracy of health worker-conducted single parasternal long-axis view with a sweep of the heart using hand-carried ultrasound for the detection of RHD in high-risk populations in Timor-Leste and Australia. In the primary analysis, the presence of any mitral or aortic regurgitation met the criteria for a positive screening result. Sensitivity and specificity were calculated for a screen-and-refer approach based on nonexpert practitioner assessment (approach 1) and for an approach using offsite expert review of nonexpert practitioner-obtained images to decide onward referral (approach 2). Each participant had a reference test performed by an expert echocardiographer on the same day as the index test. Diagnosis of RHD was determined by a panel of three experts, using 2012 World Heart Federation criteria.

RESULTS

The prevalence of borderline or definite RHD among 3,329 participants was 4.0% (95% CI, 3.4%-4.7%). The sensitivity of approach 1 for borderline or definite RHD was 86.5% (95% CI, 79.5%-91.8%), and the specificity was 61.4% (95% CI, 59.7%-63.1%). Approach 2 achieved similar sensitivity (88.4%; 95% CI, 81.5%-93.3%) and improved specificity (77.1%; 95% CI, 75.6%-78.6%).

CONCLUSION

Nonexpert practitioner-obtained single parasternal long-axis view with a sweep of the heart images, reviewed by an offsite expert, can detect borderline and definite RHD on screening with reasonable sensitivity and specificity. Brief training of nonexpert practitioners with ongoing support could be used as an effective strategy for scaling up echocardiographic screening for RHD in high-risk settings.

Handheld echocardiographic screening for rheumatic heart disease by non-experts in rural South Kordofan, Sudan: Supporting task shifting for control of a serious disease

BACKGROUND

Rheumatic heart disease (RHD) is a major and preventable cause of cardiac morbidity in Sudan. It can be detected early with a handheld echocardiography (HHE) machine. Our study aimed to screen for RHD in rural South Kordofan and to investigate the ability of non-experts to obtain good quality HHE records.

METHODS

A cross-sectional study was conducted in South Kordofan, Sudan. A team of non-experts was trained for two weeks on handheld echocardiographic screening for RHD using a simplified protocol. Cases were recorded and reviewed by a pediatric cardiologist. Demographic and clinical features of screened subjects were studied. Descriptive statistics were presented as "number (%)" or "mean ± SD". RHD frequency was expressed as cases per 1000, and the Chi-Square test/Fisher's Exact test was used to compare RHD findings between different groups.

RESULTS

A total of 467 subjects were screened. Echocardiographic quality was acceptable in 93% of recorded studies, hence 452 cases were included in the analysis. The disease frequency was found to be 50 per 1000. Out of 452 screened subjects (age 10-25 years), 23 were found to have RHD. The disease was mild in 70% and moderate or involving two valves in 30% of patients. Risk factors for the disease included the father's occupation and the village of residence.

CONCLUSION

Shortly trained non-expert medicals can assist in RHD surveillance in remote areas using HHE for early detection and management. South Kordofan state is highly endemic to RHD and a control program needs to be implemented.

High burden of rheumatic heart disease confirmed by echocardiography among Pacific adults living in New Zealand

BACKGROUND

Despite numerous echocardiographic screening studies of children in high incidence acute rheumatic fever (ARF)/rheumatic heart disease (RHD) communities, little is known about the prevalence of RHD in adults in these populations.We sought to determine the prevalence of RHD in an urban area of South Auckland, New Zealand, where previous studies had shown the prevalence of RHD in children to be around 2%.

METHODS

A cross-sectional screening study was conducted between 2014 and 2016. Echocardiography clinics were conducted at an urban Pacific-led primary healthcare clinic in New Zealand. Eligible persons aged 16-40 years were recruited according to a stratified randomised approach. Echocardiograms were performed with a standardised image acquisition protocol and reported by cardiologists.

RESULTS

There were 465 individuals who underwent echocardiograms. The overall prevalence of RHD (define and borderline) was 56 per 1000 (95% CI 36 to 78 per 1000). Definite RHD was found in 10 individuals (4 of whom were already under cardiology review at a hospital clinic) with a prevalence of 22 per 1000 (95% CI 9 to 36 per 1000). Non-rheumatic cardiac abnormalities were found in 29 individuals.

CONCLUSIONS

There is a high burden of both rheumatic and non-rheumatic cardiac abnormalities in this population. Rates described in New Zealand are as high as lower-middle-income countries in Africa. Addressing knowledge gaps regarding the natural history of RHD detected by echocardiography in adults is a priority issue for the international RHD community.

Reasons for disagreement between screening and standard echocardiography in primary care: data from the PROVAR + study : Disagreement between screening and standard echo

We aimed to evaluate the reasons for disagreement between screening echocardiography (echo), acquired by nonexperts, and standard echo in the Brazilian primary care (PC). Over 20 months, 22 PC workers were trained on simplified handheld (GE VSCAN) echo protocols. Screening groups, consisting of patients aged 17-20, 35-40 and 60-65 years, and patients referred for clinical indications underwent focused echo. Studies were remotelyinterpreted in US and Brazil, and those diagnosed with major or severe HD were referred for standard echoperformed by an expert. Major HD was defined as moderate to severe valve disease, ventriculardysfunction/hypertrophy, pericardial effusion or wall-motion abnormalities. A random sample of exams wasselected for evaluation of variables accounting for disagreement. A sample of 768 patients was analyzed, 651(85%) in the referred group. Quality issues were reported in 5.8%, and the random Kappa for major HD between screening and standard echo was 0.51. The most frequent reasons for disagreement were: overestimation of mitral regurgitation (MR) (17.9%, N=138), left ventricular (LV) dysfunction (15.7%, N=121), aortic regurgitation (AR) (15.2%, N=117), LV hypertrophy (13.5%, N=104) and tricuspid regurgitation (12.7%, N=98). Misdiagnosis of mitral and aortic morphological abnormalities was observed in 12.4% and 3.0%, and underestimation of AR and MR occurred in 4.6% and 11.1%. Among 257 patients with suspected mild/moderate MR, 129 were reclassified to normal. In conclusion, although screening echo with task-shifting in PC is a promising tool in low-income areas, estimation of valve regurgitation and LV function and size account for considerable disagreement with standard exams.

Bridging the gap between science and indigenous cosmologies: Rheumatic Heart Disease Champions4Change

Australia has articulated a commitment to eliminate rheumatic heart disease (RHD) by 2031. Business as usual will not achieve this goal. Diverse sectors need to work together in implementing complementary strategies towards this ambitious target. Rheumatic Heart Disease Australia’s ‘Champions4Change’ program is one important element that provides a novel and vital approach. Champions4Change is a culturally safe program of people living with acute rheumatic fever (ARF) and rheumatic heart disease (RHD). The Champions support each other, advocate for ending RHD, design education and awareness programs and inform resource and program development through their lived experiences. New approaches that acknowledge the complex and challenging environments in which ARF/RHD exist are required to eliminate RHD and improve care for those living with ARF/RHD. Approaches taken by the program include local engagement, improved capacity and opportunities for Champions and their communities to make self-determined decisions based on culturally informed information. This paper highlights success stories using culture and locally appropriate approaches to improve community knowledge and awareness of RHD. We describe the rationale, development and purpose of Champions4Change, illustrating how this is far more than a peer-support group, and provides benefits for health services and researchers, as well as empowering community members.

Rheumatic heart disease prevalence in Namibia: a retrospective review of surveillance registers

BACKGROUND

Rheumatic heart disease (RHD) is the most commonly acquired heart disease in children and young people in low and middle-income settings. Fragile health systems and scarcity of data persist to limit the understanding of the relative burden of this disease. The aims of this study were to estimate the prevalence of RHD and to assess the RHD-related health care systems in Namibia.

METHODS

Data was retrieved from outpatient and inpatient registers for all patients diagnosed and treated for RHD between January 2010 to December 2020. We used descriptive statistics to estimate the prevalence of RHD. Key observations and engagement with local cardiac clinicians and patients helped to identify key areas of improvement in the systems.

RESULTS

The outpatient register covered 0.032% of the adult Namibian population and combined with the cumulative incidence from the inpatient register we predict the prevalence of clinically diagnosed RHD to be between 0.05% and 0.10% in Namibia. Young people (< 18 years old) are most affected (72%), and most cases are from the north-eastern regions. Mitral heart valve impairment (58%) was the most common among patients. We identified weaknesses in care systems i.e., lack of patient unique identifiers, missing data, and clinic-based prevention activities.

CONCLUSION

The prevalence of RHD is expected to be lower than previously reported. It will be valuable to investigate latent RHD and patient follow-ups for better estimates of the true burden of disease. Surveillance systems needs improvements to enhance data quality. Plans for expansions of the clinic-based interventions must adopt the "Awareness Surveillance Advocacy Prevention" framework supported by relevant resolutions by the WHO.