Aortic stenosis is present in 2% to 9% of older patients and is the leading clinically significant valvular disorder in the elderly. The etiologies for aortic stenosis in this age group include calcification of a normal tricuspid aortic valve, calcification of a congenital bicuspid valve, and rheumatic valve disease.
Aortic stenosis in 90% of patients older than 65 years is caused by calcification of a tricuspid valve. The causes of aortic valvular calcification are unclear, although the process bears many similarities to atherosclerosis; both diseases are characterized by lipid deposition, inflammation, neoangiogenesis, and calcification. Even though the bicuspid aortic valve is the most common adult congenital cardiac anomaly and is present in approximately 2% of births, only one-third will progress to aortic stenosis with valve degeneration most frequently presenting in the fourth to sixth decade of life. Thus, it is not a major cause of aortic stenosis in the elderly. Similarly, rheumatic disease similarly presents earlier in life and often in association with mitral valve disease.
Clinical Presentation and Diagnosis
Aortic stenosis has a long asymptomatic period of latency, when the only finding is a harsh, late-peaking, crescendo–decrescendo systolic murmur that radiates to the carotids and is best heard over the right, second interspace: The second heart sound (S2) may be paradoxically split. Characteristically, aortic stenosis is associated with “pulsus parvus et tardus”: meaning the patient has a weak and diminished pulse with a late upstroke that is most easily noted in the carotids. However, these characteristic physical findings may be less obvious both in the elderly, because of the effects of aging on the vascular bed, and when the ventricle starts to fail.
The American Heart Association recommends evaluation of early systolic, midsystolic grade 3 or greater, late systolic, or holosystolic murmurs with echocardiography. Older patients may present with ominous murmurs owing to aortic valve sclerosis without significant valvular stenosis. Aortic stenosis is graded as mild, moderate, or severe (Table 77-1).
Table 77-1 Echocardiographic Findings in Aortic Stenosis ||Download (.pdf)
Table 77-1 Echocardiographic Findings in Aortic Stenosis
Aortic valve area (cm2)
Mean gradient (mm Hg)
On average, the rate of progression of disease has been estimated at an increase in jet velocity of 0.3 m/s/yr with an associated reduction in valve area of 0.1 cm2/yr. Despite these average rates of disease progression, the rate for any one individual is difficult to predict; therefore, asymptomatic patients with mild-to-moderate disease should be followed on a regular basis.
Aortic sclerosis is defined as aortic valve thickening without outflow tract obstruction. This pathology is present in 25% of patients older than 65 years and 48% of those older than 75 years; it is ...