27 Coarctation of aorta
Salient features
History
• Symptoms are usually those of hypertension: headache, epistaxis, dizziness, and palpitations
• Claudication (caused by diminished blood flow the legs)
• Occasionally, diminished blood
• Patients sometimes seek medical attention because they have symptoms of heart failure or aortic dissection. Women with coarctation are at particularly high risk for aortic dissection during pregnancy.
Examination
• The upper torso is better developed than the lower part (as the lower body has chronic low systolic blood pressure compared to the upper part).
• The systolic arterial pressure is higher in the arms than in the legs, but the diastolic pressures are similar; therefore, a widened pulse pressure is present in the arms. (Note: This condition results in hypertension in the arms. Less commonly, the coarctation is immediately proximal to the left subclavian artery, in which case a difference in arterial pressure is noted between the arms.)
• Radial pulse on the left side may be less prominent.
• The femoral arterial pulses are weak and delayed (simultaneous palpation of the brachial and femoral arteries using the thumbs is the most convenient method of comparing pulsations in the upper and lower limbs).
• A systolic thrill may be palpable in the suprasternal notch.
• Heaving apex caused by left ventricular enlargement.
• A systolic ejection click (caused by a bicuspid aortic valve which occurs in 50% of cases) is frequently present, and the second heart sound is accentuated.
• A harsh systolic ejection murmur may be identified along the left sternal border and in the back, particularly over the coarctation.
• Scapular collaterals are visible (listen over these collaterals for murmur).
• A systolic murmur, caused by flow through collateral vessels, may be heard in the back.
• In about 30% of patients with aortic coarctation, a systolic murmur indicating an associated bicuspid aortic valve is audible at the base.
Advanced-level questions
What are the types of aortic coarctation?
Common
• Infantile or preductal where the aorta between the left subclavian artery and patent ductus arteriosus is narrowed. It manifests in infancy with heart failure. Associated lesions include patent ductus arteriosus, aortic arch anomalies, transposition of the great arteries, ventricular septal defect.
• Adult type: the coarctation in the descending aorta is juxtaductal or slightly postductal. It may be associated with biscuspid aortic valve or patent ductus arteriosus. It commonly presents between the ages of 15 and 30 years.
