Prevalence and clinical significance of cardiac murmurs in neonates

Abstract

Aim: To determine the prevalence and clinical significance of murmurs detected during routine neonatal examination.

Methods: In a two year prospective study, 7204 newborn babies underwent routine examination by senior house officers. All those with murmurs underwent echocardiographic examination. All babies presenting later in infancy were also identified, to ascertain the total prevalence of congenital heart disease in infancy.

Results: Murmurs were detected in 46 babies (0.6%) of whom 25 had a cardiac malformation. The most common diagnosis was a ventricular septal defect, although four babies had asymptomatic left heart outflow obstruction. A further 32 infants from the same birth cohort had a normal neonatal examination but were found to have a cardiac malformation before 12 months of age.

Conclusions: The neonatal examination detects only 44% of cardiac malformations which present in infancy. If a murmur is heard there is a 54% chance of there being an underlying cardiac malformation. Parents and professionals should be aware that a normal neonatal examination does not preclude a clinically significant cardiac malformation. The detection of a murmur should prompt early referral to a paediatric cardiologist for diagnosis or appropriate reassurance.