Atrial Septal Defect (ASD) is a congenital heart anomaly characterized by an abnormal opening between the atria, the upper chambers of the heart. This opening, known as the septum, fails to close properly during fetal development, resulting in a passage between the left and right atria. The size and location of the defect influence the impact on heart function. Small ASDs may be asymptomatic and go unnoticed, while larger defects can pose a risk of complications, such as arrhythmias, pulmonary hypertension, or stroke. Diagnosis involves a comprehensive evaluation, including physical examinations, imaging tests, and echocardiograms. Treatment approaches vary, ranging from monitoring for small, asymptomatic defects to surgical repair or catheter-based procedures for larger or symptomatic cases. Ongoing advancements in medical technology and treatment strategies contribute to improved outcomes for individuals with ASD, emphasizing the importance of regular follow-up care to manage and monitor heart health effectively.