Congenitally Corrected Transposition of the Great Arteries

Congenitally corrected transposition of the great arteries (ccTGA) is characterized by atrioventricular and ventriculoarterial discordance, with an incidence of 0.5% of all congenital heart disease. In ccTGA, the morphological left ventricle connects to the right atrium and the pulmonary artery and the right ventricle to the left atrium and the aorta.1 ccTGA may present as situs solitus or situs inversus. Of these, situs inversus, characterized by mirror-image atria and a right-sided systemic right ventricle, is uncommon, representing just 34% of ccTGA. The pathogenesis of ccTGA is currently unknown and is considered multifactorial. We present a unique case of fraternal twins with ccTGA and primary ciliary dyskinesia (PCD). One twin has ccTGA with situs solitus, whereas his twin brother has ccTGA with situs inversus and dextrocardia. Our aim is to outline the similarities and differences between the twins through their echocardiographic and electrocardiographic findings.Fraternal twin males, without prenatal diagnosis, were born at 36 weeks’ gestation and were well at birth. On day 1 of life, they developed respiratory distress and tachypnea. A chest radiograph was suspicious for dextrocardia in twin B, yet twin A had levocardia (Figure 1). Subsequent echocardiographic findings confirmed ccTGA in both twins; but twin A had situs solitus, whereas twin B had situs inversus (Figures 2 and 3). The electrocardiographic findings …