Normal changes of LV contractility with ageing: an echocardiographic study

Purpose: Data about the natural changes of intrinsic LV contractility with age are sparse. We have recently proposed a novel echocardiographic approach to estimate LV contractility non-invasively by the slope of segmental passive stretch (preS) and systolic strain (SS) relationship. In this study we apply it in healthy volunteers of various age to detect how LV contractility changes with age in healthy hearts. Methods: In 54 healthy subjects from 21 to 70 years of age TDI (FR ∼200 Hz) of 6 LV walls were acquired. For each wall, base mid and apical regional strain curves were extracted with custom software, setting the reference point at the onset of P wave on ECG. PreS was measured as the peak positive strain after the P wave and SS as total systolic shortening. For each subject a linear regression line was estimated through 18 segmental preS and SS values. The study population was divided in 5 age groups by decades of years. Mean preS-SS relations were determined as an average slope and intercept in each group. Results: No differences of LV ejection fraction, systolic blood pressure or heart rate were observed between the groups. Mitral inflow A wave velocity and E wave deceleration time increased and E/A decreased significantly with age. A significant increase of LV PreS was observed with age, whereas SS remained unchanged. PreS and SS correlated in all subjects (mean r2=0.68). The slopes of PreS-SS relationship did not differ between the age groups while the intercept increased decreased slightly, but not significantly with increasing age (Fig. 1). Figure 1. preS-SS relationships and means Conclusion: The slope of the stretch-strain relationship did not change with age showing that intrinsic LV contractility remains unaltered in a healthy aging heart. It is in concordance with the results of recently published invasive study.