Chemically modified chitosan anti-adhesion membrane preventing postoperative pericardial adhesions in rabbit myocardial infarction model

Objective To evaluate the efficacy of a chemically modified chitosan anti-adhesion membrane for preventing postoperative pericardial adhesions in rabbit myocardial infarction model. Methods Twenty-five Japanese white rabbits underwent myocardial infarction by ligation of coronary artery after thoracotomy, and devided into treatment and control groups randomly. The treatment group had a chitosan anti-adhesion membrane placed between the heart and retrostemal injured surfaces, while control group received nothing. Then Chest was subsequently closed. Eleven rabbits survived the operation in each group. After a period of 3 months, there were 8 rabbits alive in control group and 9 rabbits alive in treatment group. The animals were examined by Cine magnetic resonance imaging. sacrificed under anesthesia, and independent observers, blinded to treatment, graded the formation of pericardial adhesions by magnetic resonance cinema and histologioal anatomy respectively. Data were analyzed by Wilcoxon' s rank test. Results Cine magnetic resonance imaging revealed that there were 2,2,4 cases of mild adhesion, moderate adhesion,and severe adhesion in group, and 7, 2, 0 respectively (P<0.05). Thoracotomy indicated there were 1,1,2,4 cases of adhesions, mild adhesions, moderate adhesions, and severe adhesions in group A, and 3, 4, 2, 0 in group B respectively (P < 0. 05). Conclusion Placement of a chemically modified chitosan anti-adhesion membrane between injured surfaces effectively reduced the formation of postoperative pericardial adhesion in rabbits of myocardial infarction model. Key words: Myocardial infarction; Model, animal; Tissue adhesions; Chitosan; Magnetic resonance imaging