Which cardiac abnormality poses the least maternal risk during pregnancy?

Atrial septal defect is a congenital heart condition characterized by an opening in the septum that divides the two upper chambers of the heart (the atria). During pregnancy, the hemodynamic changes are generally well tolerated by women with this condition. Atrial septal defects typically allow for a moderate shunting of blood between the two atria but usually do not lead to significant compromise in maternal hemodynamics or oxygen delivery. Importantly, in many cases, women with an atrial septal defect can manage their pregnancy without the development of heart failure or serious complications.

In contrast, conditions like moderate aortic stenosis can lead to increased cardiac workload and may result in complications such as heart failure or arrhythmias due to the increased blood volume and changes in hemodynamic status that occur during pregnancy. Marfan syndrome with aortic root involvement presents a significant risk due to the potential for aortic dissection, which is a life-threatening condition. Ventricular septal defects can also lead to increased pulmonary blood flow, heart failure, and other serious maternal and fetal complications. Therefore, atrial septal defect is considered the least risky among the cardiac abnormalities listed during pregnancy, allowing women with this condition to approach pregnancy with a more favorable