Poor femoral pulses may indicate which congenital condition?

• A. Patent ductus arteriosus
• B. Ventricular septal defect
• C. Coarctation of the aorta
• D. Hypoplastic left heart

Answer: (C)

Poor femoral pulses point to reduced blood flow to the lower body from an obstruction in the aorta beyond the vessels that supply the upper body. The classic condition causing this pattern is coarctation of the aorta, where narrowing after the subclavian artery lowers distal perfusion. As a result, the femoral pulses are weak or delayed, while upper-extremity pulses may be normal or even stronger, and there can be a difference in blood pressure between the arms and legs. In a sick neonate, this can reflect ductal-dependent systemic circulation and may require prostaglandin E1 to keep the ductus open until repair. Other congenital lesions tend to present with different pulse findings: for example, patent ductus arteriosus often gives a wide pulse pressure with bounding pulses, ventricular septal defect usually has normal or hyperdynamic pulses, and hypoplastic left heart can cause very weak pulses when ductal support fails—but the hallmark pattern of diminished distal perfusion due to aortic narrowing makes coarctation the most likely diagnosis.