Screening for rheumatic heart disease: evaluationof a simplified echocardiography-based approach

Abstract

Portable echocardiography has emerged as a potential tool to detect rheumatic heart disease (RHD) early. Complexechocardiographic criteria used in recent epidemiological studies may be difficult to translate into daily practice inareas where the burden of RHD is greatest and skilled practitioners are lacking. The aim of this study was to evaluatea simplified echo approach for RHD screening among children in low-income countries.Retrospective analysis of data from a cross-sectional echocardiography-based study carried out in 2005 through theexamination of 2170 school children in Maputo, Mozambique. We aimed to evaluate the value of a reference set ofcriteria (defined as a combination of Doppler and morphological rheumatic features of the aortic and/or mitralvalves) compared with an easy-to-use single mitral regurgitation jet-length criterion (simplified set of criteria). All sus-pected lesions (according to reference or simplified criteria) detected in the field by a portable echo machine werereassessed by non-portable echocardiography and then read by three independent experts. Definite RHD cases inboth groups were finally ascertained according to the reference criteria. Portable echocardiography detected valveregurgitation in 208 children. According to the reference criteria, 18 children were detected with suspected RHD onsite. 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 weresubsequently confirmed to have definite RHD, giving an estimated prevalence of 5.1 per 1000 (95% CI: 2.5–9.1)(P¼0.12, exact McNemar test). When compared with the reference criteria, the simplified approach yields amaximum sensitivity of 73% for case detection, with a positive predictive value of 92%.Simplified echocardiography-based screening for RHD appears feasible, allowing rapid and appropriate detection of asignificant number of RHD cases on site.