Layer-specific speckle tracking echocardiography in evaluating alterations of myocardial mechanics in mice models of physiological aging / 中华老年医学杂志

ABSTRACT

Objective:To explore alterations of myocardial mechanics in mice models of physiological aging.Methods:Mice aged from 3 weeks to 24 months were chosen(n=50). Conventional echocardiography and layer speckle tracking echocardiography(LS-STE)were applied to evaluate alterations of myocardial mechanics in different ages(each for 10 mise). Pathological myocardial alterations in the aging process were detected using HE and Masson's trichrome staining.Results:Clear age-dependent changes in mice of different ages were observed when assessed using parameters of conventional echocardiography( P<0.05 for all). Values from parameters of LS-STE also showed that longitudinal, circumferential and radial strain in both the endocardium and the epicardium gradually decreased during physiological aging( P<0.05 for all). Compared with the 3-weeks old group, longitudinal strain in the endocardium was significantly reduced in the 14-months old group[(-23.49±2.32) vs.(-17.19±2.28), P<0.05]; Compared with the 3-weeks old group, radial strain, longitudinal strain in the endocardium, longitudinal strain in the epicardium, circumferential strain in the endocardium and circumferential strain in the epicardium were significantly reduced in the 24-months old group[(32.90±5.01) vs.(21.80±5.54), (-23.49±2.32) vs.(-15.44±2.27), (-13.23±3.19) vs.(-7.59±2.21), (-25.93±4.09) vs.(-20.31±4.08), (-9.30±1.92) vs.(-6.01±1.04), P<0.05)]; HE and Masson's trichrome staining of the myocardium indicated increases in the cross-sectional area of cardiomyocytes and fibrosis during the aging process. Conclusions:LS-STE can accurately detect early cardiac dysfunction and pathological myocardial alterations associated with aging in mice and may serve as an effective tool in evaluating anti-myocardial aging.