[Assessment of bovine pericardium (tutomesh®) and coated polypropylene (proceed®) in the para-oesophageal position in a pig model].

BACKGROUND

Hiatal hernias are nowadays increasingly treated with meshes. Often, biological implants are being used for this application. Oesophageal perforations have been reported as rare but serious complications from the application of synthetic meshes at the oesophageal hiatus. The role of the different mesh types has not been clearly established by experimental research so far. In the present large animal model, we investigated two implant types (Tutomesh® and Proceed®) with respect to their biocompatibility and mechanical stability.

MATERIAL AND

METHODS

We used 12 domestic pigs aged three months. Tutomesh® and Proceed® were implanted in 6 animals each for bridging at the oesophageal hiatus. After a follow-up of 3 months, the experiment was terminated. We performed endoscopy and intraoperative macroscopic evaluation of the situs. In representative histological sections, established histopathological and immunohistochemical parameters of biocompatibility were investigated and tensile strength testing was performed on standardised tissue samples.

RESULTS

One animal of the Proceed® group had grade 2 oesophagitis. None of the animals had an oesophagus arrosion. The analysis of adhesions revealed slightly less adhesions in the Tutomesh® group. There was no significant difference with respect to the investigated inflammation response and immune response between both meshes. The most substantial finding of the mechanical analysis was a loss of tear strength of the Tutomesh®-tissue-complex of 30 % as compared to native tissue and more than 50 % compared to Tutomesh® prior to implantation, respectively.

CONCLUSIONS

After 3 months, there was no significant difference between the two implant types with respect to the inflammatory response. The loss of tear strength of the Tutomesh®-tissue-complex at the oesophageal hiatus is probably clinically not relevant and may be explained by the so-called biological remodeling of biological materials. The remodeling depends on the extent of the cross-linking of the respective material. It is expected that biological hernia implants, such as Tutomesh®, may have a marked potential for avoiding complications at the oesophageal hiatus in the long run. This potential cannot be proven after 3 months from our data. Further experimental investigations are necessary to clarify this issue, in particular with respect to the long-term results.