MCQ : CHD-08
An 8-Year-Old girl with cardiac murmur. Asymptomatic.
What’s your diagnostic suspicion?
A – Dilated cardiomyopathy
B – Ebstein’s anomaly
C – Congenital corrected transposition of the great arteries
D – Non-compaction cardiomyopathy
Right answer is C: Congenital corrected transposition of the great arteries
Congenitally corrected transposition of the great arteries (ccTGA) is characterized by the presence of discordant connections at both the atrioventricular and ventriculoarterial junctions.
ccTGA is due to abnormal looping of the primitive cardiac tube to the left (l-loop) instead of to the right as in the normal embryonic development of the heart (d-loop). ccTGA is a rare lesion with a prevalence of 0.03 in 1000 newborns accounting for approximately 0.05% of all congenital heart defects.
In the patient with isolated ccTGA, situs solitus and normal atrial arrangement, systemic venous blood enters the morphologic right atrium which is connected by a mitral valve with a morphologic left ventricle. This left ventricle pumps the blood into a discordantly connected transposed pulmonary artery. Pulmonary venous return is received by the left atrium which is connected via a tricuspid valve with a morphological right ventricle which supports the transposed aorta.
