A cardiac examination indicates a fixed split S2 and holosystolic murmur in a 21-year-old woman. What condition is suggested?

A fixed split S2 is a characteristic finding in conditions that involve changes in blood flow dynamics, particularly those affecting the right side of the heart. In this case, the fixed splitting of the second heart sound (S2) primarily suggests an increased blood flow to the right side of the heart, leading to delayed closure of the pulmonary valve. This phenomenon is typically seen in an atrial septal defect (ASD), where there is an abnormal opening in the septum separating the atria. This allows blood to shunt from the left atrium to the right atrium, increasing the volume of blood entering the right ventricle and subsequently the pulmonary artery.

The presence of a holosystolic murmur, which occurs throughout systole, also supports this diagnosis. In the context of ASD, the left-to-right shunt leads to right ventricular volume overload, which can result in changes to the heart's valves. However, the murmur is more characteristic of conditions like ventricular septal defect (VSD) or mitral regurgitation. In this case, while the holosystolic murmur is less common specifically for ASD, a VSD murmur would present similarly but is distinguished by other clinical signs.

Therefore, the