Prevalence of Rheumatic heart disease in childhood and adolescence in Iranian population

We studied 320,000 school children aged 6-20 years in province Zanjan during 3 years (1991-1993) to determine the prevalence rate of Rheumatic heart disease (RHD). The examination method was uniform and performed by a uniformly trained and instructed medical staff. All suspected cases of RHD were referred to Zanjan heart center where then underwent a complete cardiovascular examination. A heart disease was suspected only in 0.25% of the examined children. In 37% of them the suspicion was not confirmed, 7% had mitral valve prolapse, 15% (Females 10%, males 19%) had innocent heart murmur and 41% revealed to have a Rheumatic or congenital heart disease. The rate of RHD was 0.36 cases per 1000 children. The most common RHD consisted to MR 35.8%, MR/MS 17.9%, MS 16.4%, MS/AI 7.5% and AS/AI 7.5%. Unexpectedly, the prevalence rate of Rheumatic fever/Rheumatic heart disease in this study was, compared with that of other socio-economically comparable countries, lower (0.36 per 1000). This may be caused by prevalence of young age groups in this study. The rate of MR, the most common sequela of ARF, was the highest finding in this study. The rate of MS, a late sequela of ARF, was 16.4% in this study. So, according to slow progress of RF sequel and with respect to the fact that 20% of ARF attacks are silent, it should be expected that several cases of MVP worsen to MR as the age progresses. Therefore, public should be made aware of the benefits of early-onset treatment of pharyngitis, medical staff treat pharyngitis and/or RF/RHD properly and care for prophylaxis of bacterial endocarditis