A 5-year-old child has elevated blood pressure in the upper extremities with mottling of feet and a systolic ejection murmur at the left infraclavicular region radiating to the back. Which condition is most likely?

A 5-year-old child has elevated blood pressure in the upper extremities with mottling of feet and a systolic ejection murmur at the left infraclavicular region radiating to the back. Which condition is most likely?

• A. Aortic stenosis
• B. Coarctation of the aorta
• C. Patent ductus arteriosus
• D. Pulmonic stenosis

Answer: (B)

The pattern you’re seeing points to coarctation of the aorta, a congenital narrowing of the aorta that creates a high pressure in the arteries of the arms and a reduced pressure flow to the legs. When the narrowing is just after the branches to the head and arms, the blood pressure in the upper extremities becomes elevated while the lower extremities receive less blood, so you may see mottling or poor perfusion in the feet. The systolic murmur heard from the left infraclavicular region and radiating to the back comes from turbulent blood flow across the narrowed segment and from collateral vessels that develop around the chest wall, which often produce a murmur best felt or heard in the back. Other conditions don’t fit this combination as neatly. Aortic stenosis tends to produce a systolic murmur at the right upper sternal border with possible signs of left ventricular outflow obstruction, but it doesn’t typically cause a pressure gradient favoring the arms over the legs or leg mottling. Patent ductus arteriosus causes a continuous “machinery” murmur and wide pulse pressures, not the described upper-limb–lower-limb gradient with leg mottling. Pulmonic stenosis causes a murmur best heard at the left upper sternal border and isn’t associated with differential blood pressures between arms and legs.

The pattern you’re seeing points to coarctation of the aorta, a congenital narrowing of the aorta that creates a high pressure in the arteries of the arms and a reduced pressure flow to the legs. When the narrowing is just after the branches to the head and arms, the blood pressure in the upper extremities becomes elevated while the lower extremities receive less blood, so you may see mottling or poor perfusion in the feet. The systolic murmur heard from the left infraclavicular region and radiating to the back comes from turbulent blood flow across the narrowed segment and from collateral vessels that develop around the chest wall, which often produce a murmur best felt or heard in the back.

Other conditions don’t fit this combination as neatly. Aortic stenosis tends to produce a systolic murmur at the right upper sternal border with possible signs of left ventricular outflow obstruction, but it doesn’t typically cause a pressure gradient favoring the arms over the legs or leg mottling. Patent ductus arteriosus causes a continuous “machinery” murmur and wide pulse pressures, not the described upper-limb–lower-limb gradient with leg mottling. Pulmonic stenosis causes a murmur best heard at the left upper sternal border and isn’t associated with differential blood pressures between arms and legs.