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 (39.4% 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

Rheumatic heart disease in pregnancy: strategies and lessons learnt implementing a population-based study in Australia

Background The global burden of rheumatic heart disease (RHD) is two-to-four times higher in women, with a heightened risk in pregnancy. In Australia, RHD is found predominantly among Aboriginal and Torres Strait Islander peoples. Methods This paper reviews processes developed to identify pregnant Australian women with RHD during a 2-year population-based study using the Australasian Maternity Outcomes Surveillance System (AMOSS). It evaluates strategies developed to enhance reporting and discusses implications for patient care and public health. Results AMOSS maternity coordinators across 262 Australian sites reported cases. An extended network across cardiac, Aboriginal and primary healthcare strengthened surveillance and awareness. The network notified 495 potential cases, of which 192 were confirmed. Seventy-eight per cent were Aboriginal and/or Torres Strait Islander women, with a prevalence of 22 per 1000 in the Northern Territory. Discussion Effective surveillance was challenged by a lack of diagnostic certainty, incompatible health information systems and varying clinical awareness among health professionals. Optimal outcomes for pregnant women with RHD demand timely diagnosis and access to collaborative care. Conclusion The strategies employed by this study highlight gaps in reporting processes and the opportunity pregnancy provides for diagnosis and re/engagement with health services to support better continuity of care and promote improved outcomes.The authors gratefully acknowledge aid from the Australian National Health and Medical Research Council (NHMRC) project grant #1024206 and NHMRC Postgraduate Scholarship #11332944; University of Technology Sydney Chancellor’s Research Scholarship; and END RHD Centre of Research Excellence, Telethon Kids Institute, University of Western Australia

Searching for a technology-driven acute rheumatic fever test: The START study protocol

Introduction: The absence of a diagnostic test for acute rheumatic fever (ARF) is a major impediment in managing this serious childhood condition. ARF is an autoimmune condition triggered by infection with group A Streptococcus. It is the precursor to rheumatic heart disease (RHD), a leading cause of health inequity and premature mortality for Indigenous peoples of Australia, New Zealand and internationally. Methods and analysis: Searching for a Technology-Driven Acute Rheumatic Fever Test\u27 (START) is a biomarker discovery study that aims to detect and test a biomarker signature that distinguishes ARF cases from non-ARF, and use systems biology and serology to better understand ARF pathogenesis. Eligible participants with ARF diagnosed by an expert clinical panel according to the 2015 Revised Jones Criteria, aged 5-30 years, will be recruited from three hospitals in Australia and New Zealand. Age, sex and ethnicity-matched individuals who are healthy or have non-ARF acute diagnoses or RHD, will be recruited as controls. In the discovery cohort, blood samples collected at baseline, and during convalescence in a subset, will be interrogated by comprehensive profiling to generate possible diagnostic biomarker signatures. A biomarker validation cohort will subsequently be used to test promising combinations of biomarkers. By defining the first biomarker signatures able to discriminate between ARF and other clinical conditions, the START study has the potential to transform the approach to ARF diagnosis and RHD prevention. Ethics and dissemination: The study has approval from the Northern Territory Department of Health and Menzies School of Health Research ethics committee and the New Zealand Health and Disability Ethics Committee. It will be conducted according to ethical standards for research involving Indigenous Australians and New Zealand Mā ori and Pacific Peoples. Indigenous investigators and governance groups will provide oversight of study processes and advise on cultural matters

Surgery for rheumatic heart disease in the Northern Territory, Australia, 1997-2016: what have we gained?

Background: Between 1964 and 1996, the 10-year survival of patients having valve replacement surgery for rheumatic heart disease (RHD) in the Northern Territory, Australia, was 68%. As medical care has evolved since then, this study aimed to determine whether there has been a corresponding improvement in survival. Methods: A retrospective study of Aboriginal patients with RHD in the Northern Territory, Australia, having their first valve surgery between 1997 and 2016. Survival was examined using Kaplan-Meier and Cox regression analysis. Findings: The cohort included 281 adults and 61 children. The median (IQR) age at first surgery was 31 (18-42) years; 173/342 (51%) had a valve replacement, 113/342 (33%) had a valve repair and 56/342 (16%) had a commissurotomy. There were 93/342 (27%) deaths during a median (IQR) follow-up of 8 (4-12) years. The overall 10-year survival was 70% (95% CI: 64% to 76%). It was 62% (95% CI: 53% to 70%) in those having valve replacement. There were 204/281 (73%) adults with at least 1 preoperative comorbidity. Preoperative comorbidity was associated with earlier death, the risk of death increasing with each comorbidity (HR: 1.3 (95% CI: 1.2 to 1.5), p50 mm Hg before surgery (HR 1.9 (95% CI: 1.2 to 3.1) p=0.007) were independently associated with death. Interpretation: Survival after valve replacement for RHD in this region of Australia has not improved. Although the patients were young, many had multiple comorbidities, which influenced long-term outcomes. The increasing prevalence of complex comorbidity in the region is a barrier to achieving optimal health outcomes

Are minor echocardiographic changes associated with an increased risk of acute rheumatic fever or progression to rheumatic heart disease?

Background: The World Heart Federation criteria for the echocardiographic diagnosis of rheumatic heart disease (RHD) include a category "Borderline" RHD which may represent the earliest evidence of RHD. We aimed to determine the significance of minor heart valve abnormalities, including Borderline RHD, in predicting the future risk of acute rheumatic fever (ARF) or RHD.\ud \ud Methods: A prospective cohort study of Aboriginal and Torres Strait Islander children aged 8 to 18 years was conducted. Cases comprised children with Borderline RHD or other minor non-specific valvular abnormalities (NSVAs) detected on prior echocardiography. Controls were children with a prior normal echocardiogram. Participants underwent a follow-up echocardiogram 2.5 to 5 years later to assess for progression of valvular changes and development of Definite RHD. Interval diagnoses of ARF were ascertained.\ud \ud Results: There were 442 participants. Cases with Borderline RHD were at significantly greater risk of ARF (incidence rate ratio 8.8, 95% CI 1.4-53.8) and any echocardiographic progression of valve lesions (relative risk 8.19, 95% CI 2.43-27.53) than their Matched Controls. Cases with Borderline RHD were at increased risk of progression to Definite RHD (1 in 6 progressed) as were Cases with NSVAs (1 in 10 progressed).\ud \ud Conclusions: Children with Borderline RHD had an increased risk of ARF, progression of valvular lesions, and development of Definite RHD. These findings provide support for considering secondary antibiotic prophylaxis or ongoing surveillance echocardiography in high-risk children with Borderline RHD