ECG in a patient with L-transposition of the great arteries

Electrocardiogram (ECG) performed in pediatric patient with isolated L-transposition of the great arteries. Note the absence of initial Q waves that are typically seen in leads V5 and V6 (lateral precordial leads), as well as the abnormal presence of initial Q waves in leads V3R and V1 (anterior precordial leads). These findings represent the abnormal depolarization sequence of the interventricular septum present in ventricular inversion.