Validation of a simplified score for predicting latent rheumatic heart disease progression using a prospective cohort of Brazilian schoolchildren

OBJECTIVES: Echocardiographic (echo) screening is an important tool to estimate rheumatic heart disease (RHD) prevalence, but the natural history of screen-detected RHD remains unclear. The PROVAR+ (Programa de RastreamentO da VAlvopatia Reumática) study, which uses non-experts, telemedicine and portable echo, pioneered RHD screening in Brazil. We aimed to assess the mid-term evolution of Brazilian schoolchildren (5–18 years) with echocardiography-detected subclinical RHD and to assess the performance of a simplified score consisting of five components of the World Heart Federation criteria, as a predictor of unfavourable echo outcomes. SETTING: Public schools of underserved areas and private schools in Minas Gerais, southeast Brazil. PARTICIPANTS: A total of 197 patients (170 borderline and 27 definite RHD) with follow-up of 29±9 months were included. Median age was 14 (12–16) years, and 130 (66%) were woman. Only four patients in the definite group were regularly receiving penicillin. PRIMARY AND SECONDARY OUTCOME MEASURES: Unfavourable outcome was based on the 2-year follow-up echo, defined as worsening diagnostic category, remaining with mild definite RHD or development/worsening of valve regurgitation/stenosis. RESULTS: Among patients with borderline RHD, 29 (17.1%) progressed to definite, 49 (28.8%) remained stable, 86 (50.6%) regressed to normal and 6 (3.5%) were reclassified as other heart diseases. Among those with definite RHD, 13 (48.1%) remained in the category, while 5 (18.5%) regressed to borderline, 5 (18.5%) regressed to normal and 4 (14.8%) were reclassified as other heart diseases. The simplified echo score was a significant predictor of RHD unfavourable outcome (HR 1.197, 95% CI 1.098 to 1.305, p<0.001). CONCLUSION: The simple risk score provided an accurate prediction of RHD status at 2-year follow-up, showing a good performance in Brazilian schoolchildren, with a potential value for risk stratification and monitoring of echocardiography-detected RHD.