The Effects of Aging and Physical Activity on Doppler Measures of Diastolic Function

Abstract

Healthy aging results in changes in Doppler measures of diastolic function. It is unclear whether these alterations are a specific manifestation of the aging process or reflect a cardiac adaptation to a more sedentary lifestyle. It was hypothesized that healthy, but sedentary, aging would result in slowing of diastolic filling and myocardial relaxation, whereas lifelong endurance training would prevent such changes. Doppler data were measured in young subjects and sedentary and fit seniors across a broad range of loading conditions. Thirteen sedentary healthy (70 ± 4 years) and 12 fit Masters athlete (68 ± 3 years) seniors were recruited. Twelve young healthy (32 ± 9 years) subjects were used for comparison. Pulmonary capillary wedge pressure and Doppler variables were measured at the 6 loading conditions of baseline (twice), -15 and -30 mm Hg lower body negative pressure, and 2 levels of saline solution infusion. Doppler variables consisted of early and late mitral inflow velocity (E/A) ratio, isovolumetric relaxation time (IVRT), tissue Doppler velocities (TDI E mean ), and propagation velocity of mitral inflow. Aging resulted in a decrease in E/A ratio (p <0.001), TDI E mean (p <0.001), and propagation velocity of mitral inflow (p <0.001) and an increase in IVRT (p = 0.001). Lifelong endurance training did not completely prevent the changes in E/A ratio (p = 0.212), IVRT (p = 0.546), or propagation velocity of mitral inflow (p = 1.00). Fit seniors were able to achieve E/A ratios of 1.0 during baseline and saline solution infusion. TDI E mean was higher in fit versus sedentary seniors at baseline (p = 0.012) and during maximal lower body negative pressure (p = 0.036), but not during saline solution infusion (p = 0.493). In conclusion, age-associated abnormalities in Doppler measures of myocardial filling and relaxation are only partially minimized by lifelong endurance training and therefore may be more specific to the aging process than secondary to years of deconditioning.Normal aging, even in the absence of co-morbidities, results in marked changes in Doppler measures of ventricular filling and relaxation, including reversal of the early and late mitral inflow velocities (decreased E/A ratio) and prolongation of isovolumetric relaxation time (IVRT). 1 These variables, although reproducible, have several limitations in their ability to accurately reflect diastolic function, including significant preload dependence and lack of specificity for dynamic relaxation processes. 2 In addition, it is unclear whether alterations in these Doppler variables with senescence are a specific manifestation of the aging process or reflect a secondary cardiac adaptation to a more sedentary lifestyle. Recently, our laboratory showed that static left ventricular stiffness markedly increased during healthy sedentary aging, whereas lifelong endurance training preserved static left ventricular compliance. 4 These data showed that ≥1 component of diastole, namely static chamber compliance, was significantly influenced by fit...

Effect of exercise training on biologic vascular age in healthy seniors

“…One limitation of the present study is that the number of sedentary participants was relatively small, primarily because this study was performed as a part of comprehensive cardiovascular physiological study involving a very long period of controlled training (1,12,28,30,36). The observation that a difference was not observed in the Modelflow aortic age even after 1 yr of exercise training could be potentially explained by the small number of subjects.…”

“…In brief, Masters athletes were consistent age-group place winners at regional and national endurance events and had participated in regular competitions for 23 Ϯ 8 yr with a weekly running mileage of 32 Ϯ 10 miles or equivalent swimming or cycling (1). Left ventricular pressure-volume relations and Doppler indexes for left ventricular diastolic function in these subjects before and after training were previously reported (1,12,30). All subjects were rigorously screened for the presence of hypertension, obstructive coronary artery disease, or structural heart disease by use of 24-h blood pressure recordings, baseline and exercise ECG, and echocardiogram.…”

Increased left ventricular twist, untwisting rates, and suction maintain global diastolic function during passive heat stress in humans

“…It is well known that reductions in venous return and thus filling pressures will significantly reduce both early mitral inflow velocity and mitral annular velocities (11,20,26,29). Mild unloading (Ϫ30 mmHg of lower body negative pressure) has been shown to reduce E wave velocities from 77 to 53 cm/s and E= in the lateral wall from 15.0 to 10.1 cm/s (11).…”

Effect of aging on cardiac function during cold stress in humans

“…However, cold-induced increases in afterload may obscure the ability to detect the effect of increased inotropy on the Frank-Starling relation as afterload and inotropy shift the curve in opposite directions. Thus, it is possible that cold-induced increases in left ventricular filling pressure offset increases in afterload to maintain stroke volume in young adults, but that the same increase in left ventricular filling pressure is unable to maintain stroke volume in older adults due to reductions in left ventricular compliance and diastolic function with age (1,16,25,32,35) without a compensatory increase in inotropy.…”