What is the most important predictor for pregnancy complications in a woman with a ventricular septal defect?

The severity of the defect is indeed the most important predictor for pregnancy complications in a woman with a ventricular septal defect. A significant ventricular septal defect can lead to a higher volume load on the heart, which may complicate hemodynamics during pregnancy. Increased cardiac output demand during pregnancy can exacerbate structural defects, especially if the defect allows for significant left-to-right shunting.

In cases of a more severe defect, the risks of pulmonary hypertension, heart failure, and other complications are notably increased. Therefore, understanding the severity allows healthcare providers to better assess risks and manage the pregnancy appropriately, guiding monitoring and intervention strategies.

While factors such as the patient's age, presence of arrhythmia, and history of heart failure also contribute to overall risk, they do not encapsulate the direct physiological impact of the defect itself on pregnancy, making severity the primary concern in this context.