Coarctation of the Aorta: The Daily PANCE Blueprint
A 16-year-old boy is referred after two school screenings found a right arm blood pressure of 158/94. He feels well apart from headaches and legs that ache and feel tired after running. He has no chest pain and no syncope, his growth and development have been normal, and he takes no medications. A chest radiograph obtained by the referring clinician shows notching along the inferior margins of the posterior ribs and a subtle indentation of the descending aorta. Which of the following findings would you most expect on physical examination?
A. Bounding femoral pulses with a widened pulse pressure
B. A continuous machinery murmur below the left clavicle
C. An abdominal bruit with equal blood pressures in all four limbs
D. Femoral pulses that are weak and arrive later than the radial pulses, with the arm pressure well above the leg pressure
E. Pulsus paradoxus with jugular venous distention
Answer and topic summary
The answer is D. Femoral pulses that are weak and arrive later than the radial pulses, with the arm pressure well above the leg pressure
Diminished, delayed femoral pulses with an arm-to-leg pressure gradient — the brachial-femoral (radiofemoral) delay — is the bedside hallmark of coarctation of the aorta. Everything about the exam falls out of one anatomic fact: the aorta is discretely narrowed just distal to the left subclavian artery, near the ligamentum arteriosum. Blood reaches the arms and head before the narrowing, so those vessels see high pressure; everything downstream sees less. That is why the thigh pressure sits below the arm pressure and why the femoral pulse is both weak and late. Palpating the radial and femoral pulses simultaneously takes three seconds and is the single most useful maneuver here — and it is missed constantly, because almost nobody does it. A late systolic murmur is heard best posteriorly, over the left interscapular area, where the turbulent jet actually sits. Given years to develop, collateral flow through the intercostal arteries enlarges those vessels and erodes the undersurface of the ribs, producing the rib notching on this boy’s film; the indented descending aorta gives the classic "3 sign." Confirm with echocardiography, then map the anatomy with CT or MR angiography before repair. Two associations are worth memorizing: coarctation accompanies a bicuspid aortic valve in more than half of patients, and it is the cardiac lesion of Turner syndrome — so a short girl with a webbed neck and hypertension needs her femoral pulses checked. Repair is surgical or catheter-based with stenting, and it should not wait: untreated coarctation drives left ventricular hypertrophy, premature coronary disease, aortic dissection, and berry aneurysm rupture. Sorting the distractors: bounding femoral pulses with a wide pulse pressure point the opposite way — toward aortic regurgitation or a large left-to-right shunt, not an obstruction; a continuous machinery murmur below the left clavicle with bounding peripheral pulses is a patent ductus arteriosus; an abdominal bruit with equal four-limb pressures is renal artery stenosis, which raises pressure everywhere including the legs; and pulsus paradoxus with jugular venous distention belongs to cardiac tamponade, which has nothing to do with this presentation.
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