Archive for November, 2017

VANISHING CARDIAC MURMUR ON STANDING POSITION IS NONPATHOLOGICAL, DR.D.K.JHA,M.D

Sunday, November 26th, 2017

Cardiac murmur on routine clinical examination of children is not uncommon.

It affects approximately 65%-80% children in school going age.

It is the most disturbing clinical finding revealed to parents.

Clinicians are compelled to confirm its pathological nature by referring the child to cardiologists and getting a costly test done in the form of echocardiography.

Moreover,this echocardiography test is not available everywhere.

According to a study by Dr.Bruno Lefort and colleagues from Gatien de Clocheville Children hospital,Tours University hospital centre France, a cardiac murmur in children aged 2-18 years auscultated in supine position with no other cardiac sign and symptom and no family history of heart disease is almost always nonpathological, if the murmur vanishes when auscultated making the child in standing position.

In their study of 100 children with cardiac murmur in supine position that disappeard on standing position ,only 2 children were proved to have pathological murmur.

In the France study during 2014-2015,194 children referred consequitevely to cardiologist were first auscultated in supine position,then on  standing position and then echocardiography were done.The average age of the children was 6-7 years and most of them were boys.

30(15%) children were indentified as having pathological murmur by echocardiography in this study.

Murmur persisted on  standing position in 93% and decreased in intensity in 43%(p<0.001) children among pathological group. Among physiological group ,murmur persisted on standing position in 40% and decreased in intensity in 80%(p<0.001)

Abnormalities identified on decreasing order of incidence were Atrial septal defect(ASD),significant mitral regurgitation(MR),ventricular septal defect(VSD)and Aortic stenosis(AS)

The positive predictive value of excluding pathological murmur by its complete disappearance on standing position is 98%(95% confidence interval 93%-100%) with a specificity of 93%(95%confidence interval 78%-99%).Sensivity of this simple clinical examination was remarkably lower at 60%(95% confidence interval52%-67%)

Nonpathological or what we call an innocent cardiac murmur result from a normal blood flow through heart and great vessels. The cause of disappearnce of these physiological murmur on switching from supine to standing position is decreased venous return,left ventricular size and stroke volume.

Thus ,by the simple clinical examination of auscutating the heart in supine and then on standing position , a costly and not easily available echocardography may be avoided in most children with innocent cardiac murmur.

REFERENCES

Ann Fam Med. Published online November 13, 2017. Abstract

http://www.annfammed.org/content/15/6/523.full