Three-layered synthetic pericardial substitutes reduce postoperative pericardial adhesions.
BACKGROUND
The development of postoperative pericardial adhesions increases the risk of cardiac reoperations. The purpose of this study was to test a new pericardial substitute (UBE sheet; UBE Industries, Ltd, Tokyo, Japan) that consists of 3 layers, namely, a middle layer of polyester inserted between 2 layers of silicone-urethane copolymer.


METHODS
Before implantation into the animals, platelet adhesion to the UBE sheet was evaluated in vitro. In the canine model, the UBE sheet (group I; n = 6) was implanted for 3 months. The development of adhesions, epicardial reactions, the shrink ratio of the patch, and macrophage infiltration to the epicardium with histologic examination were evaluated. As a control, an expanded polytetrafluoroethylene sheet (group II; n = 5) was implanted in the same manner.


RESULTS
Scanning electron microscopy of the platelets adhered to the sheet showed that the UBE sheet was superior in biocompatibility compared with the expanded polytetrafluoroethylene sheet. In the canine study, group I showed fewer adhesions than group II (median [25th percentile, 75th percentile]: 0.0 [0.0, 0.0] vs 1.0 [1.0, 2.3]; P = .003; Mann-Whitney U test), fewer epicardial reactions (1.75 [1.0, 3.0] vs 3.0 [3.0, 3.0]; P = .034), and a smaller shrink ratio (8.0% [5.5%, 12.4%] vs 31.7% [30.0%, 44.8%]; P = .006). Immunohistologic studies showed fewer macrophage infiltrations (86 [56.8, 139.3] vs 201 [161.0, 276.5] in 3 fields; P = .045) into the epicardium of group I.


CONCLUSIONS
The new 3-layered pericardial substitute clearly reduced adhesion formation. We concluded that this sheet may cause fewer adhesions and a less severe inflammatory reaction after cardiac surgery, thereby facilitating safe adhesiolysis reoperation.
Kajihara
Noriyoshi
N
Department of Cardiovascular Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Eto
Masataka
M
Oishi
Yasuhisa
Y
Boku
Noriko
N
Kuwahara
Kunio
K
Nishiguchi
Naoki
N
Kotani
Chikara
C
Morita
Shigeki
S
D000818:Animals; D001672:Biocompatible Materials; D001705:Bioprosthesis; D006348:Cardiac Surgical Procedures / Q000009:adverse effects / Q000379:methods; D004195:Disease Models, Animal; D004285:Dogs; D005260:Female; D007150:Immunohistochemistry; D008297:Male; D008422:Materials Testing; D008567:Membranes, Artificial; D008855:Microscopy, Electron, Scanning; D010496:Pericardium / Q000473:pathology* / Q000601:surgery*; D011093:Polyethylene Terephthalates / Q000737:chemistry*; D011138:Polytetrafluoroethylene / Q000737:chemistry*; D011183:Postoperative Complications / Q000517:prevention & control; D011897:Random Allocation; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D000267:Tissue Adhesions / Q000517:prevention & control*
D001672:Biocompatible Materials; D008567:Membranes, Artificial; D011093:Polyethylene Terephthalates; D011138:Polytetrafluoroethylene