What is the natural history of a small ventricular septal defect diagnosed in infancy?

• A. Most close within 12 months
• B. Require immediate patch closure
• C. Do not close
• D. Usually enlarge over time

Answer: (A)

Small ventricular septal defects that are tiny in infancy commonly seal themselves as the heart grows. The defect is often bridged by tissue from the margins of the septum, sometimes forming a small septal aneurysm that walls off the opening, so the left-to-right shunt diminishes and eventually disappears. Because the shunt is usually insignificant, these defects rarely cause symptoms or heart failure, and immediate intervention isn’t needed.

That’s why the best answer is that most close within the first year of life. Management focuses on cautious observation with serial exams and echocardiography to confirm whether spontaneous closure occurs. If a defect persists or is large with a significant shunt, then intervention might be considered later, but not for a small defect that’s likely to close on its own.

The other statements don’t fit the typical course: a small defect doesn’t usually require immediate patch closure, many do close rather than persist indefinitely, and the common trajectory is not enlargement over time.