Which characteristic is most commonly seen in children with a ventricular septal defect (VSD)?

In children with a ventricular septal defect (VSD), dyspnea on exertion is a commonly observed characteristic due to the way the defect affects blood flow and oxygenation. VSD leads to the flow of blood from the left ventricle to the right ventricle, which can increase pulmonary blood flow and result in pulmonary congestion. As children grow and become more active, they may experience difficulty breathing, especially during physical activity, due to this increased workload on their hearts and the resultant lower oxygenation of blood.

While some children with a small VSD may be asymptomatic and exhibit normal growth and development, this is not the case for those with moderate to large defects, where exertional dyspnea becomes apparent. Therefore, this symptom becomes particularly significant when considering the impact of VSD on a child's functional capacity.

In contrast, the other options are less characteristic of VSD. Chest pain is not a typical symptom, especially in young children. Frequent urination is not associated with VSD and normal growth and development, while possible in smaller defects, does not typically describe the overall population with this condition, especially as the size and impact of the defect increase.