Urinary bladder matrix scaffolds promote pericardium repair in a porcine model

AMIGO NATALIA; JUAN MARTIN RIGANTI; MAURICIO RAMIREZ; ANDREA DE LORENZI; PEDRO RENDA; ROMINA LOVERA; ARIEL PASCANER; CARLOS VIGLIANO; DAMIAN CRAIEM; THOMAS GILBERT; NATHANIEL REMLINGER; ALEJANDRO NIEPONICE

JOURNAL OF SURGICAL RESEARCH

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2020

0022-4804

Pericardium closure after cardiac surgery is recommended to prevent postoperative adhesions to the sternum. Synthetic materials have been used as substitutes, with limited results due to impaired remodeling and fibrotic tissue formation. Urinary bladder matrix (UBM) scaffolds promote constructive remodeling that more closely resemble the native tissue. Aim: Evaluate the host response to UBM scaffolds in a porcine model of partial pericardial resection. 12 Landrace pigs were subjected to a median sternotomy. A 5x7cm pericardial defect was created and then closed with a 5x7cm multilayer UBM patch (UBM group) or left as an open defect (Control group). Animals were survived for 8 weeks. Endpoints included gross morphology, biomechanical testing, histology with semi-quantitative score and cardiac function.The UBM group showed mild adhesions while the Control group showed fibrosis at the repair site, with robust adhesions and injury to the coronary bed. Load at failure (gr) and stiffness (gr/mm) were lower in the UBM group compared to the native pericardium (199.9±59.2g vs. 405.3±99.89g, P=0.0536 and 44.23±15.01g/mm vs. 146.5±24.38g/mm P=0.0025 respectively). In the UBM group, the histology resembled native pericardial tissue, with neovascularization, neofibroblasts and little inflammatory signs. In contrast, Control group showed fibrotic tissue with mononuclear infiltrates and a lack of organized collagen fibers validated with a histological score. Both groups had normal ultrasonography results without cardiac motility disorders.In this setting, UBM scaffolds showed appropriate features for pericardial repair, restoring tissue properties that could help reduce post-surgical adhesions and prevent its associated complications.