Effect of age on vascular function, LV structure and systolic and diastolic ventricular function in the adult population

Abstract

Background: Aging may be associated with decreases in aortic compliance and/or increased arterial resistance, both factors which contribute to increased arterial stiffness (arterial elastance, Ea). Arterial stiffening may increase cardiac systolic load, result in left ventricular (LV) hypertrophy and alter LV systolic and diastolic function. Hypothesis: Aging is associated with increases in arterial stiffness, LV hypertrophy, increased LV systolic stiffness and diastolic dysfunction in the population independent of sex, body size (body surface area, BSA) or the presence of cardiovascular disease. Methods: Medical record review and Doppler echocardiography were performed in a cross sectional sample of Olmsted County, MN residents (age ≥ 45). Ea (end systolic pressure/stroke volume), LV mass, a load independent index of systolic function (end systolic stress-shortening relationship, σes-FS) and a pre-load independent index of diastolic relaxation (tissue Doppler early diastolic annular velocity, E') were measured. A positive (up/rightward) shift in the σes-FS relationship is indicative of increased LV systolic stiffness and may reflect enhanced contractility and/or LV structural changes (hypertrophy or fibrosis). Multivariate analysis defined the relative effect of Age controlling for sex and BSA on these parameters in the population (n = 2042) and in the subset free from known cardiovascular disease or diabetes (No CV dis) (n = 1047). Results: See Table. Controlling for sex and BSA, Ea and LV mass increased while E' decreased with increasing Age, both in the entire population and in those with No CV dis. The σes-FS relationship was shifted up/rightward with increasing Age, both in the entire population and more dramatically so in those with No CV dis. Conclusions: Aging is associated with arterial stiffening, LV hypertrophy, increased LV systolic stiffness and diastolic dysfunction. These effects are independent of the presence of known cardiovascular disease and may explain, in part, increasing cardiovascular events with advanced age. Tabled 1 SC - Population P - Population SC - No CV dis P - No CV dis Ea 0.115 <0.0001 0.135 <0.0001 LV mass 0.117 <0.0001 0.142 <0.0001 σes-FS relationship 0.116 0.007 0.324 0.0003 E' −0.409 <0.0001 −0.286 <0.0001 SC - standardized coefficient reflects relative effect of age in multivariate analysis controlling for sex and body size Open table in a new tab SC - standardized coefficient reflects relative effect of age in multivariate analysis controlling for sex and body size