Effects of different doses of carvedilol on the prevention of left ventricular remodeling and improving hemodynamics after acute myocardial infarction in rats

Objective To investigate the effects of different doses carvedilol preventing left ventricular remodeling and improving hemodynamics after acute myocardial infarction (AMI) in rats. Methods Surviving male SD rats after left coronary artery ligation were randomly assigned to AMI control group, carvedilol 30 mg/(kg·d)group,carvedilol 2 mg/(kg·d) group. After six weeks of drug therapy, hemodynamics were made by inserting catheters and tissues were examined. Another rats served as normal control group and sham-operated group.Results The left ventricular end diastolic pressure (LVEDP) and weight of ventricule were significantly increased, maximal rate of rise and fall (± dp/dt(max)) of LV pressure were significantly decreased in the AMI group compared with the sham-operated group. In comparison with the AMI group, the LVEDP and weight of ventricule were all significantly decreased, and ±dp/dt(max) were significantly increased in the carvedilol groups. The LVEDP and the weight of left ventricule decreased more in the low-dose carvedilol group than in the high-dose group. Conclusion Carvedilol can effectively attenuate left ventricular remodeling, and improve hemodynamics after AMI in rats. Low-dose carvedilol is better than high-dose.