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.

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.

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

BACKGROUND: Echocardiographic screening can detect asymptomatic cases of rheumatic heart disease (RHD), facilitating access to treatment. Barriers to implementation of echocardiographic screening include the requirement for expensive equipment and expert practitioners. We aimed to evaluate the diagnostic accuracy of an abbreviated echocardiographic screening protocol (single parasternal-long-axis view with a sweep of the heart) performed by briefly trained, nonexpert practitioners using handheld ultrasound devices. METHODS: Participants aged 5 to 20 years in Timor-Leste and the Northern Territory of Australia had 2 echocardiograms: one performed by an expert echocardiographer using a GE Vivid I or Vivid Q portable ultrasound device (reference test), and one performed by a nonexpert practitioner using a GE Vscan handheld ultrasound device (index test). The accuracy of the index test, compared with the reference test, for identifying cases with definite or borderline RHD was determined. RESULTS: There were 3111 enrolled participants; 2573 had both an index test and reference test. Median age was 12 years (interquartile range, 10-15); 58.2% were female. Proportion with definite or borderline RHD was 5.52% (95% CI, 4.70-6.47); proportion with definite RHD was 3.23% (95% CI, 2.61-3.98). Compared with the reference test, sensitivity of the index test for definite or borderline RHD was 70.4% (95% CI, 62.2-77.8), specificity was 78.1% (95% CI, 76.4-79.8). CONCLUSIONS: Nonexpert practitioners can be trained to perform single parasternal-long-axis view with a sweep of the heart echocardiography. However, the specificity and sensitivity are inadequate for echocardiographic screening. Improved training for nonexpert practitioners should be investigated.

Surgical and percutaneous management of Aboriginal Australians with rheumatic heart disease: Timeliness and concordance between practice and guidelines.

BACKGROUND: Rheumatic heart disease (RHD) affects over 40 million people globally who are predominantly young and from impoverished communities. The barriers to valvular intervention are complex and contribute to the high morbidity and mortality associated with RHD. The rates of guideline indicated intervention in patients with significant RHD have not yet been reported. METHODS: From 2007 to 2017, we used the Australian Northern Territory Cardiac Database to identify patients with RHD who fulfilled at least one ESC/EACTS guideline indication for mitral valve intervention. Baseline clinical status, comorbidities, echocardiographic parameters, indication for intervention, referral and any interventions were recorded. RESULTS: 154 patients (mean age 38.5 ± 14.6, 66.1% female) were identified as having a class I or IIa indication for invasive management. Symptoms, atrial fibrillation and pulmonary hypertension were the most common indications for surgery (74.5%, 48.1%, 40.9%). From the onset of a guideline indication the actuarial rates of accepted referral and intervention within two-years were 66.0% ± 4.0% and 53.1% ± 4.4% respectively. Of those who were referred and accepted for intervention, 86% received it within 2 years. The rates of accepted referral for patients with class I indications were 72.5% ± 4.2% while class IIa indications were 42.5% ± 9.0% (p<0.001). CONCLUSIONS: Approximately half of Aboriginal patients with significant rheumatic mitral valve disease who met ESC/EACTS guideline indications for intervention received surgery or valvuloplasty within two-years. A significant difference in referral rates was found between Class I and Class IIa indications for valvular intervention.

Hyperendemic rheumatic heart disease in a remote Australian town identified by echocardiographic screening.

OBJECTIVES: Using echocardiographic screening, to estimate the prevalence of rheumatic heart disease (RHD) in a remote Northern Territory town. DESIGN: Prospective, cross-sectional echocardiographic screening study; results compared with data from the NT rheumatic heart disease register. SETTING, PARTICIPANTS: People aged 5-20 years living in Maningrida, West Arnhem Land (population, 2610, including 2366 Indigenous Australians), March 2018 and November 2018. INTERVENTION: Echocardiographic screening for RHD by an expert cardiologist or cardiac sonographer. MAIN OUTCOME MEASURES: Definite or borderline RHD, based on World Heart Federation criteria; history of acute rheumatic fever (ARF), based on Australian guidelines for diagnosing ARF. RESULTS: The screening participation rate was 72%. The median age of the 613 participants was 11 years (interquartile range, 8-14 years); 298 (49%) were girls or women, and 592 (97%) were Aboriginal Australians. Definite RHD was detected in 32 screened participants (5.2%), including 20 not previously diagnosed with RHD; in five new cases, RHD was classified as severe, and three of the participants involved required cardiac surgery. Borderline RHD was diagnosed in 17 participants (2.8%). According to NT RHD register data at the end of the study period, 88 of 849 people in Maningrida and the surrounding homelands aged 5-20 years (10%) were receiving secondary prophylaxis following diagnoses of definite RHD or definite or probable ARF. CONCLUSION: Passive case finding for ARF and RHD is inadequate in some remote Australian communities with a very high burden of RHD, placing children and young people with undetected RHD at great risk of poor health outcomes. Active case finding by regular echocardiographic screening is required in such areas.

The RECARDINA Study protocol: diagnostic utility of ultra-abbreviated echocardiographic protocol for handheld machines used by non-experts to detect rheumatic heart disease.

INTRODUCTION: Rheumatic heart disease (RHD) causes significant morbidity and mortality in young people from disadvantaged populations. Early detection through echocardiography screening can facilitate early access to treatment. Large-scale implementation of screening could be feasible with the combination of inexpensive standalone ultrasound transducers and upskilling non-expert practitioners to perform abbreviated echocardiography. METHODS AND ANALYSIS: A prospective cross-sectional study will evaluate an abbreviated echocardiography screening protocol for the detection of latent (asymptomatic) RHD in high-risk populations. The study will evaluate the diagnostic accuracy of health worker conducted single parasternal long axis view with a sweep using handheld devices (SPLASH) (Philips Lumify S4-1 phased array transducer). Each participant will have at least one reference test performed on the same day by an expert echocardiographer. Diagnosis of RHD will be determined by a panel of three experts, using 2012 World Heart Federation criteria. Sensitivity and specificity of the index test will be calculated with 95% CIs, to determine diagnostic accuracy of a screen-and-refer approach to echocardiography screening for RHD. Remote review of SPLASH images obtained by health workers will facilitate evaluation of the sensitivity and specificity of an alternative approach, using external review of health worker obtained SPLASH images to decide onward referral. ETHICS AND DISSEMINATION: Ethics approval was obtained from the Human Research Ethics Committee of the Northern Territory Department of Health and Menzies School of Health Research, for the project to be carried out in Timor-Leste (HREC 2019-3399), and in Australia, following review by the Aboriginal Ethics subcommittee (HREC 2019-334). Ethical and technical approval was granted in Timor-Leste, by the Institute National of Health Research Ethics and Technical Committee (1073-MS-INS/GDE/VII/2019). Study results will be disseminated in the communities involved in the study, and through peer-reviewed publications and conference abstracts. TRIAL REGISTRATION NUMBER: The Australia New Zealand Clinical Trials Registry (ACTRN12620000122954).

Pulmonary Hypertension in Central Australia: A Community-Based Cohort Study.

BACKGROUND: The burden of pulmonary hypertension (PHT) in Central Australia has not been previously studied. Our aim is to characterise the prevalence, clinical classification, and long-term survival of individuals with PHT in Central Australia. METHODS: A community-based cohort study of all individuals diagnosed with PHT in Central Australia between 2005 and 2016 was undertaken. We estimated PHT prevalence using population data, describe clinical PHT classification, and characterised long-term survival using Kaplan-Meier approaches. RESULTS: A total of 183 patients were identified (mean age 52±16years, 63% female). Of these individuals, 149 (81.4%) were of Aboriginal and Torres Strait Islander (ATSI) descent. The prevalence per 100,000 of any PHT was significantly higher In ATSI (723 [95% CI 608-839] compared to non-ATSI individuals (126 [95% CI 84-168], p<0.001). Furthermore, ATSI individuals were diagnosed at younger ages compared to non-ATSI individuals (49±15 vs 64±16years, p<0.001). Median estimated pulmonary artery systolic pressure (ePASP) was higher in patients with pulmonary arterial hypertension (PAH) compared to other causes (62 [IQR 54-69] vs 50 [IQR 44-58] mmHg, p<0.01). The median survival rate from diagnosis was 9 years (IQR 7.2-13.2). Age and ePASP were significant predictors of mortality (HR 1.05 [95% CI 1.02-1.07] and HR 1.56 [95% 1.00-2.42] respectively). CONCLUSIONS: In this community based study, we found a high burden of PHT in Central Australia. The prevalence of PHT is greater in ATSI individuals and is diagnosed at younger ages compared to non-ATSI individuals. Together with other cardiovascular diseases, PHT may be in-part contributing to the gap in life expectancy between ATSI and non-ATSI individuals.