Age related structural and functional changes in left ventricular performance in healthy subjects: a 2D echocardiographic study

Abstract

Left ventricular (LV) adaptation to aging is currently poorly understood. We aimed to characterize age related changes in LV structure and function by studying a large group of healthy subjects across a wide age range. Prospectively enrolled healthy volunteers (n = 778, 327 females; age 18 to 100 years, mean age 49.8 ± 18.1 years), were divided into 4 age groups: 18 to 34 years (n = 165); 35 to 49 years (n = 242), 50 to 79 years (n = 334) and ≥ 80 years (n = 40). All subjects underwent clinical examination, as well as comprehensive transthoracic echocardiogram [TTE]. Body mass index, systolic blood pressure (BP), and left atrial volume (p < 0.0001) increased with age while diastolic BP (p < 0.0001) decreased over time. LV mass/body surface area (BSA) and relative wall thickness increased with age (p < 0.0001) coincident with worsening parameters of diastolic function (E/A and E/Em, p < 0.0001). The ejection fraction and Sm did not change significantly. Stroke volume, ejection time index, flow rate and stroke work significantly increased with age (p < 0.01). The arterial elastance (Ea), a measure of ventricular afterload, and ventricular elastance (Ees), an index of LV systolic stiffness did not change with age nor did their ratio (Ees/Ea) the latter being an expression of ventricular-arterial coupling. Age, gender and LVM were the main independent variables associated with LV systolic function. In conclusion, LV adaptation to aging in a healthy cohort is characterized by concentric LV remodeling, increased contractility and preserved ventricular-arterial coupling.

Keywords: Aging; Echocardiography; Left ventricular function.