Application of pediatric Appropriate Use Criteria for initial outpatient evaluation of asymptomatic patients with abnormal electrocardiograms

In the pediatric Appropriate Use Criteria (AUC), abnormal electrocardiogram (ECG) in an asymptomatic patient has been rated as an "Appropriate" indication for transthoracic echocardiogram (TTE). We hypothesized that the yield of abnormal findings on TTE for this indication will be low.All asymptomatic patients (≤ 18 years) from January 1, 2015 to December 31, 2017 who underwent initial outpatient evaluation at our center and had a TTE ordered for an abnormal ECG, were included. Clinic records were reviewed to obtain ECG and TTE findings.Of the 199 study patients, 13 (6.5%) had abnormal findings. Incomplete right bundle branch block (IRBBB) had the highest yield of abnormal TTE findings (7/28), with secundum atrial septal defect being the most common (5/7); (Odds ratio (OR) compared to other ECG findings 9.2, 95% CI (2.8-29.9), P .001). OR further increased to 14.6, 95% CI (3.1-68.0), P .001 when either IRBBB, right axis deviation, or right ventricular hypertrophy were present. Left ventricular hypertrophy on ECG had only one incidental abnormality on TTE, while ST segment changes, left axis deviation, right/left atrial enlargement, premature atrial/ventricular contractions, ectopic atrial rhythm, sinus bradycardia/pause, preexcitation, low-grade atrioventricular block, and junctional rhythm did not yield abnormal TTEs.The yield of abnormal findings on TTE when performed for the AUC indication for an abnormal ECG in asymptomatic pediatric patients is low except when performed for ECG abnormalities suggestive of right heart disease such as IRBBB, right axis deviation, or right ventricular hypertrophy. Future revisions of the AUC document could consider further stratification of this indication and corresponding appropriateness ratings based on ECG findings rather than combining into one broad category.