Congenitally corrected transposition of the great arteries: the systemic right ventricle

L-Transposition of the great arteries (L-TGA) is characterized by atrioventricular and ventriculoarterial discordance such that the morphologic right ventricle and tricuspid valve directly provide systemic cardiac output. The ability of the right ventricle to support the systemic circulation is often complicated by associated cardiac defects which provide numerous potential mechanisms for the development of ventricular dysfunction. Theoretical risk factors for right ventricular failure include volume overload, systemic afterload, conduction and rhythm disturbances, associated left ventricular pressure and geometry, coronary artery anomalies, surgical injury, pregnancy, hypoxemia, and advancing patient age. The high prevalence of associated lesions including anomalies of the conduction system and tricuspid valve predispose these patients to systemic right ventricular failure which is likely to alter survival in this uncommon form of congenital heart disease. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.