Assessment of left ventricular myocardial systolic acceleration in diabetic rats using velocity vector imaging.
OBJECTIVE
The purpose of this study was to investigate how the myocardial acceleration during isovolumic contraction changed in rats with diabetic cardiomyopathy and a normal left ventricular ejection fraction (LVEF) by using velocity vector imaging.


METHODS
Velocity vector imaging was performed in 12 control rats and 15 rats with streptozotocin-induced diabetic cardiomyopathy 12 weeks after streptozotocin injection. The segmental radial displacement, velocity, acceleration, and percent wall thickening were measured at the mid-left ventricular (LV) level.


RESULTS
Compared to control rats, rats with cardiomyopathy had a significant decrease in the peak radial acceleration during isovolumic contraction in most segments of the LV wall (including the anterior, anterolateral, inferolateral, and inferior segments; P < .05) but a similar LVEF, fractional shortening, and segmental displacement. Rats with cardiomyopathy also had a significant increase in LV end-diastolic and end-systolic diameters when corrected for body mass (P < .001; P = .003, respectively) and a significant decrease in the radial peak systolic velocities of the inferolateral and inferior wall segments (P < .05). In addition, rats with cardiomyopathy had a significant decrease in the peak radial diastolic acceleration in most segments of the LV wall (except for the anterolateral one; P< .05) but similar peak radial diastolic velocities in all LV wall segments compared to controls. Pathologic examination in rats with cardiomyopathy revealed ultrastructural impairment of the capillary and cardiocyte without any atherosclerotic lesion in the coronary artery compared to control rats.


CONCLUSIONS
Myocardial acceleration during isovolumic contraction decreases in rats with diabetic cardiomyopathy and a preserved LVEF, suggesting the presence of regional LV systolic dysfunction.
Department of Ultrasound, PLA 210th Hospital, 116011 Dalian, Liaoning, China. fmmuzhanghaibin@hotmail.com.
Haibin
H
Zhang
Zhangrui
Z
Wei
Xiaoxing
X
Zhu
Hongling
H
Li
Ming
M
Yu
Yunyan
Y
Duan
Ting
T
Zhu
Jun
J
Zhang
Xiaodong
X
Zhou
Miaozhang
M
Zhu
D000054:Acceleration; D000465:Algorithms; D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D058065:Diabetic Cardiomyopathies / Q000139:chemically induced / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D054459:Elasticity Imaging Techniques / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D009200:Myocardial Contraction; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013311:Streptozocin; D013318:Stroke Volume; D013599:Systole; D018487:Ventricular Dysfunction, Left / Q000139:chemically induced / Q000000981:diagnostic imaging* / Q000503:physiopathology*
D013311:Streptozocin
basic science; diabetic cardiomyopathy; echocardiography; myocardial acceleration; velocity vector imaging