17. Usefulness of portable ultrasounds in screening for valvular heart disease in children

Abstract

Portable ultrasound machines are becoming increasingly useful in bedside routine exams and field surveys for early detection of heart disease. This is especially important for rheumatic heart disease (RHD) which is an emerging public health problem in developing countries. The aim of this study was to screen primary school children, with a focus on females living in rural settings, for valvular disease.Methods: A total of 465 girls aged 8–12 years were screened using portable vivid-e GE machine. All subjects were exposed to full history and clinical examination as well as a routine echo exam for left ventricular (LV) function assessed by M-Mode for fractional area shortening (FAS) and ejection fraction, assessment of mitral valve morphology, color Doppler and spectral Doppler for all four valves using pulsed and continuous wave spectral Doppler. Suspicious cases were referred to a higher center in Cairo University Children Hospital and followed up in the AFCRHD follow up clinic. Laboratory studies for anti-streptolysin-O (ASO) titer and C-reactive protein was carried out for suspicious cases. Findings: The study detected 24 children with valvular abnormality by echo examination. Mitral regurgitation (MR) was the commonest findings being detected in 21 cases (10 RHD and 11 congenital); one case with mitral stenosis (MS) of rheumatic origin, aortic regurgitation (AR) in 4 cases and stenosis in one case; tricuspid regurgitation in 4 cases and pulmonary regurgitation in one case. The MR detected was in the range of 10–30% i.e. mild to moderate, cases with trivial regurge were excluded from the study. Mitral valve thickening and decreased mobility were evident in the cases diagnosed as RHD. However one case with congenital mitral prolapse also showed valve thickening. Hence the overlap between RHD and congenital prolapse did present a diagnostic dilemma. Overall RHD was diagnosed in 13 cases (6 definite and 7 suspected). Ventricular function assessed by M-mode for FAS and EF as well as spectral Doppler findings were within the normal range for age. Epidemiological assessment showed that most of the cases with positive echo findings came from the rural areas (91.7%) and were characterized by high maternal illiteracy rates of 16.7% compared to 5.2% in the echo free cases. Increasing age, increasing number of children sleeping in one room and poor dietary habits and tendency to underweight increased the prevalence of valvular disorders detected indicating the need for screening populations at risk. We conclude that mitral valve is the most commonly affected valve. RHD is the commonest etiological factor and appears to be on the rise especially in underprivileged populations. Differentiating between rheumatic and non-rheumatic etiology for valve disease still poses a problem. We recommend that every child with suspicious RHD should be followed up carefully and the decision for prophylaxis should be based on multiple factors taking the family history, living conditions and general condition of the child into consideration. Portable echocardiography machines are the state of the art in early detection of RHD and should be recommended as the standard for diagnosis of RHD.