Prevention of retrosternal adhesion by novel biocompatible glue derived from food additives

Background: Postoperative retrosternal adhesion increases the risk of cardiac injury during cardiac reoperation. We created a novel biodegradable glue called "Lydex" that is derived from food additives. The purpose of this study is to evaluate this new biomaterial's biocompatibility and its preventive effect on retrosternal adhesion. Methods: We performed a median sternotomy and anterior pericardiectomy on Japanese white rabbits, and then closed the chest (control, group 1; n = 12), implanted an expanded polytetrafluoroethylene membrane (group 2; n = 12), or applied Lydex (group 3; n = 12) before closure. After 4 weeks, we evaluated macroscopic adhesion (each group; n = 6) and microscopic findings for fibrosis and macrophage infiltration (each group; n = 6). Results: In group 3, the retrosternal adhesion score was significantly lower than in group 1 (P = .0022). There was no significant difference between groups 2 and 3. The fibrotic area ratio was significantly lower in group 3 than in groups 1 and 2 (P < .001 vs group 1; P < .001 vs group 2). In group 3, the macrophage count was significantly lower than in group 2 (P < .001) and almost equal to that in group 1. Conclusions: Our findings indicate that Lydex reduces retrosternal adhesion and attenuates the progression of fibrosis with excellent biocompatibility. Lydex is a next-generation substance for safer cardiac reoperation, with excellent capability for preventing adhesion, biocompatible and biodegradable properties, and lower potential for viral infections related to human plasma or other animal-derived products.