The most appropriate management for this patient with a small uncomplicated ventricular septal defect (VSD) is follow-up in 3 to 5 years. She has clinical features of a small membranous VSD without associated volume overload of the left heart, pulmonary hypertension, or valve regurgitation.

Cardiac catheterization is not indicated for this patient because the echocardiogram does not demonstrate left heart enlargement or features that suggest pulmonary hypertension.

Cardiac magnetic resonance (CMR) imaging will usually demonstrate a membranous VSD and can quantitate the impact of the VSD on the left heart; however, it is not indicated in this patient because the clinical assessment and echocardiogram suggest that observation is appropriate. CMR imaging would be a reasonable test if the transthoracic echocardiogram images were not diagnostic.

Endocarditis prophylaxis is recommended for patients with congenital heart disease characterized by unrepaired cyanotic congenital heart disease, including palliative shunts and conduits; a completely repaired congenital heart defect with prosthetic material or device during the first 6 months after the procedure; and repaired congenital heart disease with residual defects. Patients with uncomplicated VSDs without a prior history of endocarditis do not require endocarditis prophylaxis.

Functional aerobic capacity measured by stress testing is not used to determine management in patients with small VSDs. A small VSD does not impact exercise capacity and thus assessment of exercise capacity will not change management in this patient.