| Objectives: To investigate if strain rate based on two-dimensional(2D) image by Velocity Vector Imaging(VVI) is correlative with cardiocyete apoptosis parameters, furthermore estimate if the strain rate based on two-dimensional(2D) can be used in quantitative diagnose of congestive heart failure and assessment of heart function .Methods: Thirty-six rabbits were randomly divided into four groups (8,8,10 and 10 rabbits in groups A,B,C and D respectively ) , and rabbits in groups B,C and D were administrated adriamycin 2mg/kg body wt every time . Intravenously once a week for 4 weeks, 6 weeks and 8 weeks respectively . Eight rabbits of the group A received 2ml/kg body wt. of normal saline once a week for 8 weeks as the control group. After 12 weeks,VVI parameters were measured. Rabbits in group D were measured left ventricular SR based on two-dimensional (2D) image by VVI at the end of 4th, 8th , 12th and at the begining of adiministrated adriamycin respectively. Apoptotic cardiomyocytes index and the expression of Bcl-2 protein and Bax protein were also detected. Results: 1.SR values of rabbits in group D in different times comparison:before administrated adriamycin , left ventricular systolic SR curves of every rabbits ventricular segments illustrated that the time of peak SR were uniform, and appear distinctive colour strips on two-dimensional(2D) image by VVI , the values of SR fluctuated at -1.731～-2.157 . Among the every rabbits left ventricular segments, the values of systolic SR were not significant difference in statistics. The experiment did not appear SR values decreased gradually from apex to basal of left ventricular. With the time of administrated adriamycin increasing, rabbits strain and SR absolute values of all segments of left ventricle were decreasing. Comparison to normal self-rabbit, there was significant statistic difference in longitudinal(P<0.05) . Compare rabbits SR values of all segments of left ventricle in every two groups, there was also significant statistic difference. In cross section, the results were available as well.2.Rabits systolic SR values in groups A,B,C and D in 12th comparison : with accumulated dose of administrated adriamycin increasing , rabbits left ventricular systolic SR absolute values in groups A,B,C and D were decreasing . And there were significant difference in every two groups.3.The correlation analysis between SR values by VVI and cardiocyete apoptosis index/ the expression of Bcl-2 protein and Bax protein respectively:the expression of Bcl-2 protein in rabbits groupB,C and D are lower than group A markedly(P<0.01),however apoptotic cardiomyocyetes / the expression of Bax protein were distinctively higher than group A(P<0.01). Comparison of every two groups on apoptosis index/the expression of Bcl-2 protein and Bax protein in rabbits of groups B,C and D , there were significant difference(P<0.05)in statistics. In longitudinal section, systolic SR of left ventricular wall were significantly negative correlated with the expression of Bcl-2 protein in rabbits of all the four groups(r=-0.72, P <0.01), and myocyte apoptosis index, Bax had a significant positive correlation (r1 =0.81,r2 = 0.69, P <0.01). In cross section, systolic SR of left ventricular wall were significantly negative correlated with the expression of Bcl-2 protein in rabbits of four groups(r = -0.70, P <0.01), and myocyte apoptosis index, Bax had a significant positive correlation (r1 =0.79,r2 =0.67, P <0.01).CONCLUSION : The SR based on 2D imaging by VVI can quantitatively assess myocardial injury and heart function in the process of congestive heart failure.
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