Objective: To study the relationship between changes in pulmonary artery pressure and changes in right ventricular function.
Methods: MCT-induced 4 pulmonary arterial hypertension (PAH) model groups (12 in each group), pulmonary artery pressure was measured by right heart catheter for 1, 2, 3, and 4 weeks, and MRI right heart function test was used to dynamically observe the changes of pulmonary artery pressure and MRI parameters . Compare the differences in related parameters between the control group and the PAH model group. Using SPSS17.0 statistical software, Pearson correlation analysis was used to evaluate the correlation between right ventricular ejection fraction, right ventricular end diastolic volume, right ventricular end systolic volume and mean pulmonary artery pressure. We used a completely random t-test. In the comparison between the groups, P\u003c0.05 indicated significant difference.
Results: 1-4 weeks after single-color injection, the right ventricular ejection fraction, right ventricular end-diastolic and end-systolic volumes of the 48 model rats have a good correlation with the mean pulmonary artery pressure (rRVEF =-) 0.823. RVEDV = 0.732, rRVESV = 0.803). Two weeks before monocrotalin injection, the average pulmonary artery pressure, right ventricular ejection fraction, right ventricular end-diastolic and end-systolic volumes of the monopolytalin group were not significantly different from those of the control group (P\→0.05). After 3-4 weeks, the above parameters were significantly different from the control group (P\u003c0.05).
Conclusion: With the increase of pulmonary artery pressure in rats, the right ventricular ejection fraction gradually decreases, and the right ventricular end-diastolic and end-systolic volumes gradually increase. In order to monitor the rat model of chronic pulmonary hypertension, MRI can accurately and quickly measure the changes of various parameters. The end-diastolic and end-systolic volumes, ejection fraction and other parameters of the right ventricle are sensitive parameters that cause pulmonary hypertension.