The PVAM samples were reticulated by electron beam radiation and manipulated into a tube shape. After thoracotomy, the pericardium of Wistar rats was opened to expose the heart. Rats were treated by pushing the heart back into the thoracic cavity (Sham group), sprinkling the epicardium with talcum powder (Talc group), encircling the heart with PVAM (PVAM group), or sprinkling the epicardium with talcum powder before placing the PVAM to encircle the heart (PVAM + Talc group). Animals were recovered for 8 weeks and then euthanized. Macroscopic findings (ie, extent and severity of adhesions) were classified according to a 4-grade adhesion scale. The PVAM was tested for direct and indirect cytotoxicity with Vero cells. The water absorption capability and in聽vivo calcification after 8 weeks of subcutaneous implantation of the membrane were examined. Data were analyzed by analysis of variance and Bonferroni post hoc tests.
The PVAM group had lower adhesion scores than the Talc and Sham groups, as well as reduced epicardium thickness and inflammatory cell results, compared with the Talc and PVAM + Talc groups. The聽PVAM exhibited no direct or indirect cytotoxicity, good water absorption capability (42.4% 卤 0.9%), and negligible calcification after 8 weeks (4.42聽脳聽10鈭? 卤 2.56聽脳聽10鈭? percentage of the total mass).
The PVAM shows promising properties for its potential use as a novel pericardial substitute.