pediatrics
Transposition of the Great Arteries (TGA)
Diagnosis of TGA
Chest x-ray and ECG Echocardiography Diagnosis of transposition of the great arteries is suspected clinically, supported by chest x-ray and ECG, and established by 2-dimensional echocardiography with color flow and Doppler studies. On chest x-ray, the cardiac shadow may have the classic egg-on-a-string appearance with a narrow upper mediastinum. ECG shows right axis deviation and right ventricular hypertrophy but may be normal for a neonate. Cardiac catheterization is not usually necessary for diagnosis but may be done to enlarge the atrial communication (balloon atrial septostomy) or to further elucidate complex coronary artery anatomy. 