What type of murmur is associated with atrial septal defect?

Atrial septal defects (ASDs) are characterized by a flow of blood from the left atrium to the right atrium due to the presence of an abnormal opening in the atrial septum. This left-to-right shunt increases the blood volume in the right atrium and subsequently in the right ventricle, leading to several characteristic auscultatory findings.

The distinctive murmur associated with an ASD is a systolic ejection murmur due to increased blood flow across the pulmonary valve. This murmur can be described as relatively soft and can be accentuated in certain positions (such as sitting or standing). Additionally, a hallmark of ASD is the presence of a fixed splitting of the second heart sound (S2). This fixed splitting occurs because the right atrium fills earlier and empties later due to the increased volume of blood, causing the pulmonary valve to remain open longer than normal during expiration.

This combination of a systolic ejection murmur and the fixed split S2 is what makes this choice the correct answer for the type of murmur associated with atrial septal defects. Understanding this relationship is essential for recognizing ASDs in clinical practice, as the fixed split S2 is a significant auscultatory feature that helps in the