D-Transposition of Great Arteries

D-Transposition of Great Arteries is a serious heart condition present at birth where the two main arteries leaving the heart are switched. This affects the circulatory system by causing oxygen-poor blood to circulate through the body and oxygen-rich blood to loop back to the lungs. As a result, the body does not get enough oxygen, leading to cyanosis or a bluish tint to the skin. Babies with this condition often have trouble breathing and may appear very tired or weak. The heart's structure forces blood to flow in a way that is not compatible with normal oxygen delivery, which can be life-threatening without medical intervention.

D-Transposition of Great Arteries (D-TGA) is a congenital cardiac malformation characterized by the ventriculoarterial discordance where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle. This anatomical defect results in two parallel circulations: systemic venous blood is pumped back to the body without oxygenation, and pulmonary venous blood recirculates to the lungs. The condition is caused by abnormal development of the conotruncal septum during embryogenesis. Clinically, it presents with severe cyanosis shortly after birth due to inadequate systemic oxygenation. Survival depends on the presence of intracardiac or extracardiac shunts such as an atrial septal defect, ventricular septal defect, or patent ductus arteriosus that allow mixing of oxygenated and deoxygenated blood. Without intervention, D-TGA leads to hypoxemia and can cause early neonatal death.