Published online by Cambridge University Press: 19 August 2008
The vast majority of patients with complete transposition present during either the neonatal period or early infancy. Almost always the diagnosis and the categorization of associated lesions can be established by cross-sectional echocardiography. Doppler techniques usually provide enough information about flows to allow palliative or radical surgery to be undertaken without formal cardiac catheterization, because balloon atrial septostomy is carried out with echocardiographic imaging, often on the intensive care unit. Angiography is occasionally performed to visualize the pulmonary arteries or the aorta, and, if there is suspicion of a significant elevation of the pulmonary vascular resistance, it must be measured at cardiac catheterization. Neither cross-sectional echocardiography nor aortography is entirely reliable in identifying those patterns of the coronary arteries which are a contraindication to the arterial switch operation. There is, as yet, no evidence that either magnetic resonance imaging or transesophageal echocardiography are superior to more conventional methods of preoperative diagnosis in complete transposition and it seems unlikely that they will be required.