Feasibility of assessing left ventricular myocardial morphology and function in acute and chronic myocardial hypertrophy rat models with ultrasound biomicroscopy / 中国医学影像技术

ABSTRACT

Objective: To investigate the feasibility of assessing left ventricular myocardial morphology and function in acute and chronic myocardial hypertrophy rat models induced by isoproterenol (ISO) with ultrasound biomicroscopy (UBM). Methods: Totally 40 SD rats were randomly divided into 4 groups (each n=10). Rats in acute myocardial hypertrophy model group (acute model group) were given subcutaneous injection with ISO 85 mg/kg once a day for 2 days, and those in acute control group were given equal amount saline with subcutaneous injection for equal course. Rats in chronic myocardial hypertrophy model group (chronic model group) were given subcutaneous injection with ISO 5 mg/kg once a day for 7 days, and those in chronic control group were given equal amount saline with subcutaneous injection for equal course. The following parameters, including left ventricular anterior wall diameter (LVAWD), left ventricular posterior wall diameter (LVPWD), left ventricular end diastolic diameter (LVEDD), left ventricular end systolic diameter (LVESD), left ventricular end diastolic volume (LVEDV), left ventricular end systolic volume (LVESV), left ventricular ejection fraction (LVEF), left ventricular fractional shortening (LVFS) and left ventricular myocardial mass were measured with UBM. Then the rats were sacrificed, the left ventricular myocardial masses were accurately weighed. Results: Compared with acute control group, LVAWD and LVPWD increased in acute model group (both P<0.05). Compared with chronic control group, LVAWD, LVPWD, LVESD and LVESV increased in chronic model group, while LVEF and LVFS decreased (all P<0.05). Compared with acute model group, LVEDD, LVESD, LVEDV and LVESV of chronic model group increased, but LVEF and LVFS decreased (all P<0.05). Left ventricular myocardial masses measured with UBM were higher than anatomical accurate weighing in all 4 groups (all P<0.05). Left ventricular myocardial masses of acute model group measured with both Methods: were all lower than those of chronic model group (both P<0.05). The left ventricular myocardial masses measured with UBM were positively correlated with the value measured by anatomical accurate weighing in all 4 groups (all P<0.05). Conclusion: UBM can non-invasively evaluate left ventricular morphology and function in rats with acute and chronic myocardial hypertrophy induced by ISO.