Two-dimensional speckle tracking imaging quantitative assessment of left ventricular global and regional myocardial function in normal rats / 中国医学影像技术

ABSTRACT

Objective To investigate the value of two-dimensional speckle tracking imaging (2D-STI) in assessing left ventricular global and regional myocardial function in normal rats. Methods Echocardiography was performed during low-dose dobutamine stress in 20 normal adult male Wistar rats. High frame rate of 2D images were recorded from the left ventricular short-axis views at the papillary muscle level. Peak systolic radial strain (PRS) and circumferential strain (PCS) of each segment, left ventricular global peak systolic radial strain (G_(PRS)) and circumferential strain (G_(PCS)) were measured at EchoPAC work station. Left ventricular internal diameter at diastole (LVIDd), systole (LVIDs), fractional shortening (FS) and ejection fraction (EF) were measured with anatomical M-model echocardiography. Dynamic changes of each index during stress experiment were observed. The correlations between EF and left ventricular global two-dimensional strain (G_(PRS), G_(PCS)) were analyzed respectively. Results PRS was similar in all segments of mid-ventricular in short-axis view (P>0.05) at baseline, while PCS of each segment showed heterogeneity, with the anteroseptal and anterior wall showing the largest value and the inferior wall showing the lowest value (P0.05). Conclusion With good reproducibility, 2D-STI can noninvasively and easily assess global and regional left ventricular myocardial deformation of normal rats at rest and during low-dose dobutamine stress.