A Heart Failure Model Established by Pressure Overload Caused by Abdominal Aortic Contraction in Rat

Abstract

Heart failure is a complex clinical syndrome in which ventricular filling or ejection capacity is impaired due to structural or functional diseases of the heart. In order to establish a stable heart failure model, we investigated cardiac parameters in rats with abdominal aortic contraction and normal rats, including the left ventricular posterior wall diameter (LVPWd), the interventricular septum thickness of end-diastolic (IVSd), the left ventricular end-diastolic diameter (LVEDd), the left ventricular ejection fraction (LVEF), and left ventricular fractional shortening (LVFS). Rats were randomly divided into experimental group ( $n=20$ ) and control group ( $n=20$ ). The experimental group underwent modified abdominal aortic constriction, while the control group only isolated the abdominal aorta without constriction. The results showed that the survival rate of rats in the experimental group was 85% after one week of operation, while the survival rate of rats in the control group was 100%. Five weeks after operation, the left ventricular posterior wall diameter (LVPWd) and the interventricular septum thickness of end-diastolic (IVSd) in the experimental group were all increased compared with those in the control group, and the differences were statistically significant ( $p<0.05$ ); the left ventricular end-diastolic diameter (LVEDd) in the experimental group showed an increasing trend compared with the control group, but $p>0.05$ ; compared with the control group, the left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) in the experimental group showed downward trend, but $p>0.05$ . 10 weeks after operation, the LVPWd, IVSd, and LVEDd of the experimental group were increased compared with the control group, $p<0.05$ , and the LVEF and LVFS of the experimental group were decreased compared with the control group, $p<0.05$ . Compared with the control group, the BNP of the experimental group increased significantly, $p<0.05$ . The heart weight index and left ventricular weight index of rats in the experimental group were significantly higher than those in the control group, $p<0.05$ . HE staining showed that the myocardial cells in the experimental group increased in volume, disordered cell arrangement, widened gaps, increased nuclear hyperchromia, and uneven staining. This paper provides a theoretical basis for the study of heart failure.