Evaluating cardiac murmurs; are diagnostic tests helpful?

The detection of an asymptomatic murmur in a child usually results in a referral to a consultant paediatrician. In most cases a chest radiograph (CXR) and electrocardiograph (ECG) are performed as an aid to diagnosis, however the evidence for this is contradictory. A retrospective chart review of children referred with asymptomatic cardiac murmurs in a one-year period was conducted. We wished to determine whether CXR and ECG are useful diagnostic aids. 81 patient charts were reviewed. Of those patients with a clinical diagnosis of pathological murmur all had normal CXR and ECG. Never the less 2 cases were referred for echocardiogram and were found to have structural heart disease. Of those with a clinical diagnosis of innocent murmur most (81%) had a CXR and ECG and in most cases (96%) these were normal. Those cases with abnormal investigations subsequently were shown to have structurally normal hearts on echocardiogram. We conclude that routine use of CXR and ECG in evaluating asymptomatic cardiac murmurs in children is not useful.