Echocardiographic assessment of LV hypertrophy and function in aortic-banded mice: necropsy validation.

ABSTRACT

We characterized the time course of the left ventricular (LV) geometric and functional changes after aortic banding, validated them by necropsy, and investigated the sensitivity of echocardiographic findings on LV hypertrophy. C57BL/6 mice were subjected to transverse aortic constriction (TAC) or sham operation; echocardiographic assessments were performed before or at 2, 4, 6, and 11 wk after surgery; and some of the mice were euthanized at the corresponding time points. There was a progressive increase in diastolic posterior wall thickness and LV systolic dimension; the percentage of LV fractional shortening (LV%FS) decreased progressively at 4 wk, whereas these parameters remained stable in sham-operated mice. Echo LV mass and LV%FS correlated well with actual whole heart mass and ratio of lung weight to body weight, respectively (r = 0.765 and -0.749, respectively; P < 0.0001). These results suggest that the development of myocardial hypertrophy and systolic dysfunction is a time-dependent process. Echocardiographic assessment of myocardial hypertrophy and functional changes correlate well with the actual heart mass and lung mass. Echocardiography is sensitive enough to assess myocardial hypertrophy and heart functional changes induced by pressure overload in mice.