In a child with a ventricular septal defect undergoing a cardiac catheterization, the procedure involves placing the catheter in which location?

• A. Ultra-high-frequency sound waves
• B. Catheter placed in the right femoral vein
• C. Cutdown procedure to place a catheter
• D. General anesthesia

Answer: (B)

Access through the venous system, especially the right femoral vein, is the route used for a diagnostic cardiac catheterization to evaluate a ventricular septal defect. This approach lets the catheter reach the right atrium and right ventricle and, if needed, cross the septum into the left side to measure pressures and oxygen saturations, helping determine the size and hemodynamic impact of the defect. In pediatric patients, venous access minimizes arterial complications and is the standard starting route for this evaluation. The other options describe imaging modality, a more invasive surgical exposure, or anesthesia, none of which specify where the catheter is placed.