Focused cardiac ultrasound screening for rheumatic heart disease by briefl y trained health workers: a study of diagnostic accuracy

Background Echocardiographic screening for rheumatic heart disease (RHD) can identify individuals with subclinical disease who could benefi t from antibiotic prophylaxis. However, most settings have inadequate resources to implement conventional echocardiography and require a feasible, accurate screening method. We aimed to investigate the accuracy of screening by non-expert operators using focused cardiac ultrasound (FoCUS). Methods In this prospective study of diagnostic accuracy, we recruited schoolchildren aged 5 to 15 years in Fiji to undergo two blinded tests. The index test was a FoCUS assessment of mitral and aortic regurgitation, performed by nurses after an 8-week training programme. The reference standard was the diagnosis of RHD by a paediatric cardiologist, based on a standard echocardiogram performed by a skilled echocardiographer. The primary outcome was the accuracy of the index test with use of the most sensitive criteria (any regurgitation). Findings We included 2004 children in the study. The index tests were done between September, 2012, and September, 2013, by seven nurses in eight schools in Fiji. The diagnostic accuracy of the screening test (area under receiver operator characteristic curve) was 0·89 (95% CI 0·83–0·94). When the primary cut-off point (any regurgitation) was used for analysis, sensitivity was 84·2% (72·1–92·5) and specifi city was 85·6% (83·9–87·1). The sensitivity of individual nurses ranged from 66·7% to 100% and specifi city 74·0% to 93·7%. Interpretation Screening by briefl y trained nurses using FoCUS was accurate for the diagnosis of RHD. Refi nements to training and screening test methods should be studied in a range of settings, and in parallel with investigations of the long-term clinical and cost-eff ectiveness of screening for RHD

Teaching focused echocardiography for rheumatic heart disease screening

Screening for rheumatic heart disease (RHD) requires workers skilled in echocardiography, which typically involves prolonged, specialized training. Task shifting echocardiographic screening to nonexpert health workers may be a solution in settings with limited human resources. An 8-week training program was designed to train health workers without any prior experience in focused echocardiography for RHD screening. Seven health workers participated. At the completion of training, the health workers performed unsupervised echocardiography on 16 volunteer children with known RHD status. A pediatric cardiologist assessed image quality. Participants provided qualitative feedback. The quality of echocardiograms were high at completion of training (55 of 56 were adequate for diagnosis) and all cases of RHD were identified. Feedback was strongly positive. Training health workers to perform focused echocardiography for RHD screening is feasible. After systematic testing for accuracy, this training program could be adapted in other settings seeking to expand echocardiographic capabilities

Echocardiographic screening for rheumatic heart disease in high and low risk Australian children

Background: Echocardiographic screening for rheumatic heart disease (RHD) is becoming more widespread, but screening studies to date have used different echocardiographic definitions. The World Heart Federation has recently published new criteria for the echocardiographic diagnosis of RHD. We aimed to establish the prevalence of RHD in high-risk Indigenous Australian children using these criteria and to compare the findings with a group of Australian children at low risk for RHD.\ud \ud Methods and Results: Portable echocardiography was performed on high-risk Indigenous children aged 5 to15 years living in remote communities of northern Australia. A comparison group of low-risk, non-Indigenous children living in urban centers was also screened. Echocardiograms were reported in a standardized, blinded fashion. Of 3946 high-risk children, 34 met World Heart Federation criteria for definite RHD (prevalence, 8.6 per 1000 [95% confidence interval, 6.0–12.0]) and 66 for borderline RHD (prevalence, 16.7 per 1000 [95% confidence interval, 13.0–21.2]). Of 1053 low-risk children, none met the criteria for definite RHD, and 5 met the criteria for borderline RHD. High-risk children were more likely to have definite or borderline RHD than low-risk children (adjusted odds ratio, 5.7 [95% confidence interval, 2.3–14.1]; P<0.001).\ud \ud Conclusions: The prevalence of definite RHD in high-risk Indigenous Australian children approximates what we expected in our population, and no definite RHD was identified in the low-risk group. This study suggests that definite RHD, as defined by the World Heart Federation criteria, is likely to represent true disease. Borderline RHD was identified in children at both low and high risk, highlighting the need for longitudinal studies to evaluate the clinical significance of this finding.\u

Reference exome data for Australian Aboriginal populations to support health-based research

Abstract: Whole exome sequencing (WES) is a popular and successful technology which is widely used in both research and clinical settings. However, there is a paucity of reference data for Aboriginal Australians to underpin the translation of health-based genomic research. Here we provide a catalogue of variants called after sequencing the exomes of 50 Aboriginal individuals from the Northern Territory (NT) of Australia and compare these to 72 previously published exomes from a Western Australian (WA) population of Martu origin. Sequence data for both NT and WA samples were processed using an ‘intersect-then-combine’ (ITC) approach, using GATK and SAMtools to call variants. A total of 289,829 variants were identified in at least one individual in the NT cohort and 248,374 variants in at least one individual in the WA cohort. Of these, 166,719 variants were present in both cohorts, whilst 123,110 variants were private to the NT cohort and 81,655 were private to the WA cohort. Our data set provides a useful reference point for genomic studies on Aboriginal Australians

Reference exome data for Australian Aboriginal populations to support health-based research

Abstract: Whole exome sequencing (WES) is a popular and successful technology which is widely used in both research and clinical settings. However, there is a paucity of reference data for Aboriginal Australians to underpin the translation of health-based genomic research. Here we provide a catalogue of variants called after sequencing the exomes of 50 Aboriginal individuals from the Northern Territory (NT) of Australia and compare these to 72 previously published exomes from a Western Australian (WA) population of Martu origin. Sequence data for both NT and WA samples were processed using an ‘intersect-then-combine’ (ITC) approach, using GATK and SAMtools to call variants. A total of 289,829 variants were identified in at least one individual in the NT cohort and 248,374 variants in at least one individual in the WA cohort. Of these, 166,719 variants were present in both cohorts, whilst 123,110 variants were private to the NT cohort and 81,655 were private to the WA cohort. Our data set provides a useful reference point for genomic studies on Aboriginal Australians

Reference exome data for Australian Aboriginal populations to support health-based research

Abstract: Whole exome sequencing (WES) is a popular and successful technology which is widely used in both research and clinical settings. However, there is a paucity of reference data for Aboriginal Australians to underpin the translation of health-based genomic research. Here we provide a catalogue of variants called after sequencing the exomes of 50 Aboriginal individuals from the Northern Territory (NT) of Australia and compare these to 72 previously published exomes from a Western Australian (WA) population of Martu origin. Sequence data for both NT and WA samples were processed using an ‘intersect-then-combine’ (ITC) approach, using GATK and SAMtools to call variants. A total of 289,829 variants were identified in at least one individual in the NT cohort and 248,374 variants in at least one individual in the WA cohort. Of these, 166,719 variants were present in both cohorts, whilst 123,110 variants were private to the NT cohort and 81,655 were private to the WA cohort. Our data set provides a useful reference point for genomic studies on Aboriginal Australians

World Heart Federation criteria for echocardiographic diagnosis of rheumatic heart disease: an evidence-based guideline

Over the past 5 years, the advent of echocardiographic screening for rheumatic heart disease (RHD) has revealed a higher RHD burden than previously thought. In light of this global experience, the development of new international echocardiographic guidelines that address the full spectrum of the rheumatic disease process is opportune. Systematic differences in the reporting of and diagnostic approach\ud to RHD exist, reflecting differences in local experience and disease patterns. The World Heart Federation\ud echocardiographic criteria for RHD have, therefore, been developed and are formulated on the basis of the best available evidence. Three categories are defined on the basis of assessment by 2D, continuous-wave,and color-Doppler echocardiography: 'definite RHD', 'borderline RHD', and 'normal'. Four subcategories of 'definite RHD' and three subcategories of 'borderline RHD' exist, to reflect the various disease patterns. The morphological features of RHD and the criteria for pathological mitral and aortic regurgitation are also defined. The criteria are modified for those aged over 20 years on the basis of the available evidence. The standardized criteria aim to permit rapid and consistent identification of individuals with RHD without a clear history of acute rheumatic fever and hence allow enrollment into secondary prophylaxis programs. However, important unanswered questions remain about the importance of subclinical disease (borderline or definite RHD on echocardiography without a clinical pathological murmur), and about the practicalities of implementing screening programs. These standardized criteria will help enable new studies to be designed to evaluate the role of echocardiographic screening in RHD control