[Age-induced changes in the cardiovascular system in normal subjects].

To assess the effect of age on cardiac structure and function, we performed echocardiograms on 104 physically active, normal, community-dwelling volunteers (68 men and 36 women), ranging in age from 18 to 84 years and having no evidence of hypertension or cardiovascular disease. With advancing adult aging, the following were observed: a decrease in aortic compliance (r = 0.42); an increase in systolic (r = 0.61), diastolic (r = 0.24), pulse (r = 0.60) and mean (r = 0.48) arterial pressure; and a modest enlargement of aortic root (r = 0.47) and left atrial dimension (r = 0.30) were observed. Left ventricular end-diastolic volume (r = 0.25), wall thickness (r = 0.30) and mass (r = 0.37) also increased with aging, while left ventricular end-systolic volume was not age-related. Furthermore, a stepwise multivariate linear model identified the decrease in arterial compliance (R2 = 0.06; p < 0.02) and the increase in left ventricular stroke work (R2 = 0.38; p < 0.0001) as the only variables independently related to the increase in left ventricular mass that occurs with advancing age. Regarding left ventricular systolic function, aging was also related to an increase in left ventricular stroke work (r = 0.40) and ejection time (r = 0.44), while pump function, (measured as ejection fraction and cardiac index at rest), and contractility (measured by load independent end-systolic indexes) were unaffected by aging. Conversely, pulsed Doppler analysis of mitral inflow showed a significant age-related decline in the peak early filling velocity (r = -0.45) and in the ratio of early and late diastolic filling velocity (r = -0.66), while peak late diastolic flow velocity (r = 0.50), diastolic pressure half time (r = 0.34) and duration of isovolumic relaxation (r = 0.56) increased significantly with age.