Atrial Septal Defect (ASD)

Atrial Septal Defect (ASD) is a heart condition where there is a hole in the wall between the two upper chambers of the heart, called the atria. This defect affects the cardiovascular system and allows blood to flow abnormally between the left and right atria. Because of this, oxygen-rich blood from the left atrium mixes with oxygen-poor blood in the right atrium, which can cause the heart to work harder. Over time, this extra workload can lead to heart enlargement and problems with blood flow to the lungs. Symptoms may include shortness of breath, fatigue, and sometimes heart palpitations. Many people with this condition may not notice symptoms until later in life. Early diagnosis and monitoring are important to prevent complications.

Atrial Septal Defect (ASD) is a congenital cardiac anomaly characterized by a persistent communication between the left and right atria due to incomplete formation of the interatrial septum. The most common type is the ostium secundum ASD, caused by deficient septum primum or septum secundum development. This defect results in a left-to-right shunt, increasing pulmonary blood flow and causing volume overload of the right atrium and ventricle. Chronic shunting can lead to right heart dilation, pulmonary hypertension, and eventually right heart failure if untreated. Clinically, ASDs may present with a fixed split S2 heart sound and a systolic ejection murmur due to increased flow across the pulmonary valve. The condition is significant because it can remain asymptomatic for years but predisposes to complications such as atrial arrhythmias and paradoxical embolism.