Our patient's physical examination demonstrates findings indicating coarctation of the aorta, a bicuspid aortic valve, and mild aortic regurgitation. Our patient demonstrates significant systemic hypertension with dramatically higher pressure in both arms than in the legs. This finding indicates the presence of coarctation of the aorta until proven otherwise. Coarctation of the aorta causes hypertension by its effects upon the kidney. Obstruction in the aorta results in decreased pressure, particularly pulse pressure, distal to the obstruction. The kidney responds to decreased renal artery pulse pressure by increasing secretion of renin which, in turn, increases blood pressure.
Bicuspid aortic valve
A bicuspid aortic valve occurs in up to 75% of patients with an aortic coarctation and an ejection sound is characteristic. Our patient's ejection sound is likely from a bicuspid valve, however, in other patients, an ejection sound may be due to a high velocity, large volume ejection into a dilated ascending aorta.
Aortic regurgitation
Our patient also demonstrates aortic regurgitation, based upon a typical high frequency, decrescendo diastolic murmur that begins immediately with the aortic component of S2. The short duration and low intensity of the murmur suggest the regurgitation is mild.
Hypertension in coarctation
Hypertension is a common finding in patients with coarctation, where the blood pressure in the arms is higher than in the legs. However, our patient demonstrates higher blood pressure in both the arms and legs than do most patients with coarctation of the aorta. It is possible, therefore, that his hypertension is more complex, with additional etiologies to be considered. This can have adverse implications for his future. Such patients may remain hypertensive despite correction of the coarctation.
Common types of aortic obstruction
These drawings illustrate a normal ascending aorta, aortic arch and descending aorta in panel A; typical coarctation of the aorta in panel B; a hypoplastic aortic arch between the left common carotid and left subclavian artery in panel C; and a coarctation of the aorta partially obstructing the origin of the left subclavian artery in panel D.