Assessment of electrocardiographic criteria for left atrial enlargement in childhood.

Ninety children, aged 1 day to 18 years (median 7 months), with electrocardiographic or echocardiographic evidence of left atrial (LA) enlargement were selected to determine if electrocardiographic criteria accurately reflected increased LA dimension as determined by echocardiography. Four cardiac defects known to produce LA enlargement were chosen: ventricular septal defect (24 patients), patient ductus arteriosus (25 patients), cardiomyopathy (27 patients) and mitral regurgitation (14 patients). Different electrocardiographic criteria for LA enlargement were assessed. The data indicated that the overall sensitivity and predictive value of the ECG to detect LA enlargement were 40 and 85%, respectively. The ECG and echocardiogram failed to agree in 62% of the patients. The most predictive variable for LA enlargement was the presence of a notched P wave in the limb leads with a large negative terminal deflection in lead V1. The sensitivity of ECG was highest in patients with chronic LA overload status, in mitral regurgitation (77%), cardiomyopathy (50%) and ventricular septal defect (54%). The results show that in the pediatric population, electrocardiographic criteria are moderately predictive for LA enlargement but not as sensitive as generally believed.