Echocardiographic Assessment of Cardiac Function in Mouse Models of Heart Disease

Figure 1. Standard echocardiographic views in mice. This figure illustrates the main echocardiographic views used to assess cardiac function in mice through TTE. The image is organized into three columns (1, 2, and 3), each corresponding to a different echocardiographic window. (1) Parasternal Long-Axis View (PLAX): the transducer should be parallel to the central axis of mouse body and orientated at the lower one-third of the chest with the indicator marker toward the left hip (1a); the left ventricle (LV) is visualized longitudinally along the probe’s axis, with the apex oriented towards the left side, the mitral valve (mv) is visible at the lower portion of the image, while the aortic valve (av) and the aortic root appear at the top (1b); the ultrasound image shows a PLAX view, enabling assessment of ventricular size and function (1c). (2) Parasternal Short-Axis View (PSAX): the PSAX view is obtained by rotating the transducer 90 clockwise from the PLAX view, with the indicator marker toward the right shoulder (2a); a cross-sectional view of the left ventricle (2b); the ultrasound image shows a PSAX view, enabling evaluation of ventricular wall thickness, chamber dimensions, and…

Figure 2. Assessment of left ventricular systolic function in mice. This figure illustrates echocardiographic assessments of left ventricular systolic function in mice using M-mode ultrasound imaging. (A) M-mode echocardiogram with measurements of left ventricular dimensions during systole and diastole, acquired from a parasternal long-axis (PLAX) view. (B) M-mode echocardiogram with measurements of left ventricular dimensions during systole and diastole acquired with a PSAX view.

Figure 3. Patterns of left ventricular diastolic dysfunction assessed using mitral inflow and tissue Doppler imaging. This image illustrates the progression of left ventricular diastolic dysfunction from normal function to severe impairment (Grade 3). It compares mitral inflow patterns assessed using pulsed-wave Doppler (PWD) with mitral annular diastolic velocities measured using tissue Doppler imaging (TDI). Key features include changes in the E/A ratio and e′/a′ velocities, helping to distinguish between normal relaxation, delayed relaxation, pseudonormal, and restrictive filling patterns.

Figure 4. Assessment of diastolic function in mice. This figure illustrates echocardiographic assessments of diastolic function in mice obtained from an apical four-chamber (A4C) view using pulsed-wave Doppler (PWD) and tissue Doppler imaging (TDI). (A) PWD capture transmitral flow velocities: early diastolic ventricular filling (E-wave), late diastolic ventricular filling due to atrial contribute (A-wave), and E-wave deceleration time (DT), reflecting diastolic relaxation and ventricular filling dynamics (diastasis). (B) TDI assesses myocardial tissue velocities at the mitral annulus level: early diastolic myocardial velocity (e′ wave) and late diastolic myocardial velocity (a′ wave), critical parameters for assessing myocardial relaxation properties and ventricular diastolic function.

Figure 5. Multidimensional assessment of myocardial strain using speckle-tracking echocardiography (STE). This image illustrates the three principal components of myocardial deformation assessed by STE. (A) GLS (global longitudinal strain) evaluates myocardial contraction and relaxation along the long axis of the heart, reflecting subendocardial fiber function. (B) GRS (global radial strain) measures myocardial thickening and thinning in the radial direction from the endocardium to the epicardium. (C) GCS (global circumferential strain) assesses myocardial shortening along the circular axis of the ventricle.

Figure 6. Speckle-tracking echocardiography (STE) in mice. Advanced cardiac analysis (regional and global cardiac measurements) assessed using STE (Vevo Strain 2.0, Vevo LAB analysis software; VisualSonics, Toronto, ON, Canada). (A) Global longitudinal strain (GLS), measured from a PLAX view of the left ventricle, indicates myocardial shortening during systole, represented by negative percentage values (normal reference values around −22%). (B) Global radial strain (GRS) and global circumferential strain (GCS), obtained from the PSAX view; GRS, reflecting myocardial thickening during systole, is expressed in positive percentage values (normal reference values around +35%); GCS, indicative of myocardial circumference shortening during systole, is expressed as negative percentage values (normal reference values around −30%).