Which condition is characterized by left-to-right shunts?

Atrial Septal Defect (ASD) is characterized by a left-to-right shunt, which occurs when there is an abnormal communication between the left atrium and the right atrium. This defect allows oxygen-rich blood from the left atrium to flow into the right atrium, which then leads to increased blood flow to the right side of the heart and subsequently to the lungs.

In a normal heart, the left side pumps oxygenated blood to the body, while the right side pumps deoxygenated blood to the lungs. However, with ASD, the shunting can lead to volume overload of the right atrium and right ventricle. Over time, this can cause right heart dilation and potentially lead to complications such as pulmonary hypertension.

ASD is one of the most common congenital heart defects and presents with characteristic clinical findings, particularly in older children and adults, who may experience symptoms like exertional dyspnea or fatigue due to the increased workload on the right heart.

Left-to-right shunts are a critical concept in understanding various congenital heart defects, as they typically lead to increased pulmonary blood flow and may necessitate surgical intervention if significant symptoms or complications develop. In contrast, conditions like ventricular septal defect (VSD) and