Left ventricular diastolic dysfunction assessment by tissue Doppler imaging in a suprarenal abdominal aortic coarctation model of Lewis rat / 中华超声影像学杂志

ABSTRACT

Objective To evaluate the left ventricular diastolic dysfunction by tissue Doppler imaging (TDI)in a suprarenal abdominal aortic coarctation model of Lewis rats. Methods Thirty male Lewis rats at age of 8 weeks were used. Myocardial hypertrophy model was obtained by suprarenal abdominal aorta banding with ligation. Mitral annular velocity measurement by TDI and regular two-dimensional echocardiography with M mode were examined at baseline and at 10-,20-,30-and 40-day post banding.Results Compared with baseline,the left ventricular end diastolic and end systolic wall thickness and ventricular dimension were progressively increased,while ejection fraction(EF)and fraction shortening(FS)were decreased(P＜0.0 1).The left ventricle demonstrated centrifugal myocardial hypertrophy.Peak myocardial systolic velocity(Sa)at the mitral annulus did not change significantly throughout this study and there was no significant correlation with EF(r=0.216,P=0.071),and peak myocardial early diastolic (Ea),late diastolic(Aa)at the mitral annulus and Ea/Aa indices also were not stable after aortic banding and there were no significant difference in repeated measures at different time(P＞0.05).But the E/Ea wasincreased and the index had a statistically significant difference(P＜0.001).Conclusions The left ventricleshowed centrifugal myocardial hypertrophy in Lewis rats with abdominal aortic banding.E/Ea radio was a sensitive and stable index to evaluate left ventricular diastolic dysfunction.