Experimental Research On The Influence Of Left Ventricular Aneurysm Formation To Left Ventricular Function By Echocardiography

Objective: To evaluate the relationship between left ventricular twist, left ventricularaneurysm size and left ventricular function in the rabbits with left ventricular aneurysmformed after myocardial infarction by real-time three-dimensional echocardiography(RT-3DE) combined with speckle tracking imaging(STI). Methods: Twenty-seven healthyrabbits were divided into two groups, six as control group, twenty-one as experimentalgroup. The model of myocardial infarction and ventricular aneurysm were established byligaturing left anterior descending coronary artery and left circumflex artery. After fourweeks, according to the pathological examination of whether ventricular aneurysm formedor not, the experimental group was divided into the myocardial infarct group andventricular aneurysm group. RT-3DE was performed to measure left ventricular aneurysmvolume(LVAV), left ventricular aneurysm area(LVAA), left ventricular end-diastolevolume(LVEDV), left ventricular end-systole volume(LVESV) and Left ventricularejection fraction(LVEF); STI was performed to measure rotations (at the levels of mitralannulus and apex in LV short-axis view) and LV twist. Results: Compared with thecontrol group, LVIDd and LVEDV were larger in the myocardial infarct group andventricular aneurysm group, and those were the largest in the ventricular aneurysm group.LVEF, apical rotation and LV twist were lower in the myocardial infarct group andventricular aneurysm group than the control group, and those were significantly decreasedin the ventricular aneurysm group. LVAV, LVAA, the apical rotation and LV twist hadshown a great correlation with LVEF. The areas under the ROC curve of the apicalrotation was0.831(95%CI:0.664,0.997, P=0.008), sensitivity and specificity of diagnosiscardiac dysfunction were76.9%and80%respectively when the apical rotation was 1.21°. Conclusions: There was a closely relationship between the change of apicalrotation and the left ventricular systolic function. When the apical rotation dropped to1.21°, a apparent decline of left ventricular systolic function was implied. LVAV can moreaccurate than LVAA reflect left ventricular function.