Screening for rheumatic heart disease: evaluation of a simplified echocardiography-based approach.

AIMS: Portable echocardiography has emerged as a potential tool to detect rheumatic heart disease (RHD) early. Complex echocardiographic criteria used in recent epidemiological studies may be difficult to translate into daily practice in areas where the burden of RHD is greatest and skilled practitioners are lacking. The aim of this study was to evaluate a simplified echo approach for RHD screening among children in low-income countries. METHODS AND RESULTS: Retrospective analysis of data from a cross-sectional echocardiography-based study carried out in 2005 through the examination of 2170 school children in Maputo, Mozambique. We aimed to evaluate the value of a reference set of criteria (defined as a combination of Doppler and morphological rheumatic features of the aortic and/or mitral valves) compared with an easy-to-use single mitral regurgitation jet-length criterion (simplified set of criteria). All suspected lesions (according to reference or simplified criteria) detected in the field by a portable echo machine were reassessed by non-portable echocardiography and then read by three independent experts. Definite RHD cases in both groups were finally ascertained according to the reference criteria. Portable echocardiography detected valve regurgitation in 208 children. According to the reference criteria, 18 children were detected with suspected RHD on site. Of these, 15 children (83%) were considered to have definite RHD, giving a prevalence of 6.9 per 1000 (95% CI: 3.9-11.4). The simplified mitral regurgitation jet-length criteria detected 12 children at school, 11 of whom were subsequently confirmed to have definite RHD, giving an estimated prevalence of 5.1 per 1000 (95% CI: 2.5-9.1) (P = 0.12, exact McNemar test). When compared with the reference criteria, the simplified approach yields a maximum sensitivity of 73% for case detection, with a positive predictive value of 92%. CONCLUSION: Simplified echocardiography-based screening for RHD appears feasible, allowing rapid and appropriate detection of a significant number of RHD cases on site.

Rheumatic heart disease screening by echocardiography: the inadequacy of World Health Organization criteria for optimizing the diagnosis of subclinical disease.

BACKGROUND: Early case detection is vital in rheumatic heart disease (RHD) in children to minimize the risk of advanced valvular heart disease by preventive measures. The currently utilized World Health Organization (WHO) criteria for echocardiographic diagnosis of subclinical RHD emphasize the presence of pathological valve regurgitation but do not include valves with morphological features of RHD without pathological regurgitation. We hypothesized that adding morphological features to diagnostic criteria might have significant consequences in terms of case detection rates. METHODS AND RESULTS: We screened 2170 randomly selected school children aged 6 to 17 years in Maputo, Mozambique, clinically and by a portable ultrasound system. Two different echocardiographic sets of criteria for RHD were assessed: "WHO" (exclusively Doppler-based) and "combined" (Doppler and morphology-based) criteria. Independent investigators reviewed all suspected RHD cases using a higher-resolution, nonportable ultrasound system. On-site echocardiography identified 18 and 124 children with suspected RHD according to WHO and combined criteria, respectively. After consensus review, 17 were finally considered to have definite RHD according to WHO criteria, and 66 had definite RHD according to combined criteria, giving prevalence rates of 7.8 (95% confidence interval, 4.6 to 12.5) and 30.4 (95% confidence interval, 23.6 to 38.5) per 1000 children, respectively (P<0.0001, exact McNemar test). CONCLUSIONS: Important consideration should be given to echocardiographic criteria for detecting subclinical RHD because the number of cases detected may differ importantly according to the diagnostic criteria utilized. Currently recommended WHO criteria risk missing up to three quarters of cases of subclinically affected and therefore potentially treatable children with RHD.