Prevention of retrosternal adhesions after pericardiotomy.

The research article is about a study carried out to investigate the prevention of heart and graft adhesion to the sternum after pericardiotomy, using synthetic or xenograft material. This procedure is becoming crucial as more repeat coronary bypass operations necessitate repeat sternotomies.

Study Methodology and Findings

The study relied on the use of bovine and equine glutaraldehyde-processed xenografts, which were implanted bilaterally in dogs. These implants were left in place for pre-determined intervals of 6 weeks, and 3, 6, 9, and 12 months to observe their effects over time.

• The objective was to assess the performance of these xenografts in preventing adhesion of the heart and grafts to the sternum – the condition the study aims to prevent.
• The results showed that both the bovine and equine xenografts performed effectively in preventing the heart from adhering to their inner surfaces. However, they were less successful in preventing adhesions of the lung and chest wall to their outer surfaces.
• The bovine xenograft showed a higher percentage of adhesion-free surface on all the evaluated surfaces. However, a significant observation was that one of the bovine pericardial xenograft implants that stayed in a dog for 12 months showed signs of substantial multifocal calcific degeneration. This casts doubt on the long-term effectiveness or safety of the bovine xenograft implant.

General Concerns and Recommendation

Pericardial xenografts have generally performed well when implanted in dogs. Despite the promising results, there is uncertainty about their performance or reaction in humans. The authors reference the concerns expressed by other researchers, Gallo, Artiñano, and Duran, regarding the use of these xenografts in humans, which aligns with their own findings.

• The occurrence of calcification in a bovine xenograft implanted for a longer duration adds to these concerns. Because calcification can lead to the stiffening and malfunction of the implanted material, this finding signals potential risks in real-world applications.
• In light of these findings and uncertainties, the authors recommend a cautious approach to the clinical application of pericardial xenografts. More research and testing are needed to ensure that these implants are both effective and safe for human use.