Rheumatic heart disease (RHD) among Indian children could be 20 times more than what is believed. A study conducted by the All India Institute of Medical Sciences (AIIMS) in and around Delhi to see prevalence of RHD among children in northern India found prevalence of 20.4/1000 school children as against 1 per 1000 children earlier believed. The study carried out echocardiographic screening of 6,270 randomly selected school children aged 5-15 years. RHD was twice as prevalent among children aged 11-15 years (prevalence of 26.5 per 1000 children) compared to children aged 5-10 years (12.6 per 1000 children). Girls had a higher prevalence of RHD (27.9/1000 girls) compared to boys (13.3/1000 boys). The study said though RHD was thought to be on the decline in India because of improving standards of living, the estimated prevalence of echocardiograpically detected RHD in India was comparable to those measured in Mozambique (21.5 cases per 1000). The study was published in the British journal 'Heart'. Dr S Ramakrishnan from AIIMS' department of cardiology told TOI, "Usually, doctors while carrying out a clinical examination listen to the child's heart to check for abnormal rhythms or murmurs that may signify that the heart has been strained. Only when a murmur is detected is an echocardiographic screening done. Our study has now shown that the prevalence of RHD is several fold higher using echocardiographic screening compared with clinical examination (estimated less than 1 in 1000 children)." Dr Ramakrishnan added, "Though many believe that RHD in India is dipping, we have now shown how rampant it could be." Dr Anita Saxena from the same department and lead author said RHD can cause chronic heart valve damage which can eventually lead to heart failure. She said in case of an RHD, two valves of the heart among the four get affected. The mitrial valve is the commonest sufferer. The study also showed that thickening of the mitral and/or aortic valve was present in all cases. Of the 128 children, mild valve leakage was found in 101 children, and moderate valve leakage in 11 children. "Echocardiographic screening for RHD must be done more rigorously," she said. The report said recent studies from Africa, using echoardiographic screening, had reported a nearly 10-fold higher prevalence of RHD in children. The prevalence of RHD among asymptomatic school children in India is not known. The suggested risk factors for RHD include overcrowding, poverty and unhygienic living conditions. "We carried out a large echocardiographic screening survey among asymptomatic school children living in rural areas of north India near Ballabhgarh - 40 km from AIIMS. The objectives of the study were to estimate the prevalence of clinical and subclinical RHD, to identify risk factors associated with RHD and to study the natural history of children with echocardiographically detected RHD," the authors said. The study revealed older age, female gender, studying in government funded schools, living in kutcha houses made of mud/bamboos and overcrowding as significant predictors of RHD. "Using data from the present study, the estimated number of children with echocardiographically diagnosed RHD in India alone would be nearly 6 million. Hence, RHD should be prioritised in developing countries where it remains a leading cause of cardiac morbidity and mortality," the study added.