Comparison between the decellularized bovine pericardium and the conventional bovine pericardium used in the manufacture of cardiac bioprostheses

Introduction: In this paper, our objective was to compare the decellularized and conventional pericardium mechanical resistance and also its capability of inducing inflammatory response in an animal experimental model. Methods: In order to study these properties, we divided the pericardia into two groups: Group I pericardium conventionally treated with GTA and Group II – pericardium previously decellularized and then treated with GTA in the conventional way. After the chemical treatment, Group II samples were histologically evaluated to confirm the efficacy of the decellularization process. Then, only for the analysis of mechanical resistance, pericardia were divided in: Groups 1 (conventional pericardia with criteria of approval), 2 (conventional pericardial with criteria of rejection) and 3 (decellularized pericardia). The capacity of inducing inflammatory response was tested in a rat experimental model using 50 Wistar rats, in which rats of each group received patches of the pericardia in the abdomen. Our third step of analysis was to manufacture three decellularized pericardium bioprostheses which were submitted to hydrodynamic evaluation together with a conventional bioprosthesis test. Results: The histological analysis showed complete decellularization. Mechanical resistance gave statistical differences in the “tension of rupture” and “tenacity index” tests. We found no difference in the inflammatory activity in the animal model. Hydrodynamic performance was similar and all prostheses reached 150 million cycles. The final histological analysis assessed the standard microscopic pattern and no rupture or abnormal fragmentation was caused by mechanical stress. Conclusion: The decellularization technique maintains the physical resistance of the pericardium when compared with the conventionally prepared pericardium. And also, there was no difference in both groups regarding to inflammatory response studied in the animal model. Descriptors: Heart valve prosthesis. Bioprosthesis. Pericarduim. Comparative study. Comparação entre o pericárdio bovino decelularizado e o pericárdio bovino convencional utilizado na confecção de biopróteses valvares cardíacas Comparison between the decellularized bovine pericardium and the conventional bovine pericardium used in the manufacture of cardiac