Closure of the pericardium using synthetic bioabsorbable polymers

Area of Science:

• Biomaterials Science
• Surgical Innovation
• Tissue Engineering

Background:

• Pericardial substitutes are crucial for safer reoperation after cardiac surgery.
• Expanded-polytetrafluoroethylene (e-PTFE) is a common synthetic pericardial substitute but can cause adverse inflammatory reactions and fibrosis.
• Investigating absorbable alternatives is essential to mitigate these risks.

Purpose of the Study:

• To evaluate the absorption rate and tissue response of two novel absorbable pericardial substitutes: gelatin and L-lactic acid-epsilon-caprolactone copolymer (L-C copolymer).
• To compare these absorbable materials against a widely used e-PTFE sheet and autologous pericardium in a canine model.

Main Methods:

• Sixty dogs underwent pericardial defect repair using either autologous pericardium, gelatin sheet, L-C copolymer sheet, or e-PTFE sheet.
• Implanted materials were retrieved at various time points (2, 4, 12, and 24 weeks) for analysis.
• Tissue reaction, including inflammation and adhesion, was assessed.

Main Results:

• The e-PTFE group exhibited severe adhesions to the heart and pleura, along with a pronounced inflammatory response.
• Both gelatin and L-C copolymer sheets were fully absorbed by 24 weeks post-implantation.
• Absorbable substitutes were replaced by regenerated fibrous tissue.

Conclusions:

• Gelatin sheets demonstrated significantly less adhesion and reduced inflammatory reactions compared to e-PTFE.
• Absorbable pericardial substitutes, particularly gelatin, present a promising alternative to e-PTFE, potentially improving outcomes in cardiac surgery.
• Further research into absorbable biomaterials for pericardial reconstruction is warranted.