CCI Registered Cardiac Sonographer (RCS) Practice Test

Ostium secundum atrial septal defect refers to a specific type of heart defect characterized by an abnormal opening in the atrial septum, which is the wall that separates the left and right atria of the heart. This defect occurs in the region of the septum called the ostium secundum, which is one of the sites where such openings can arise during fetal development.

The presence of this defect allows for communication between the atria, leading to oxygen-rich blood from the left atrium being mixed with oxygen-poor blood from the right atrium. This condition can result in increased blood flow to the right side of the heart and can have implications on the heart's function over time, potentially leading to heart failure or other complications if left untreated.

In the context of the other options, opening in the aortic wall refers to a different condition related to vascular abnormalities, while a defect in the ventricular septum specifically involves the wall separating the ventricles, and abnormalities of the mitral valve pertain to issues with the valve itself rather than a septal opening. Thus, the definition of ostium secundum atrial septal defect aligns specifically with an opening in the atrial septum.