In vivo evaluation of a porous, elastic, biodegradable patch for reconstructive cardiac procedures.

PURPOSE Several synthetic materials have been used for cardiac reconstruction in patients with complex congenital heart defects. These materials are not viable, do not grow with children, and may necessitate reoperation. We report here on the cardiac implantation of a recently developed, degradable porous material designed to facilitate cellular ingrowth during the healing process. DESCRIPTION An elastomeric, biodegradable polyester urethane urea (PEUU) was processed into circular scaffolds and used to replace a surgical defect in the right ventricular outflow tract of adult rats. Control rats were implanted with expanded polytetrafluoroethylene. Histologic evaluation was performed at 4, 8, and 12 weeks postsurgery. EVALUATION All animals survived the surgery. Both PEUU and expanded polytetrafluoroethylene were encapsulated with fibrous tissue and had complete endothelialization on the endocardial surface with no aneurysm formation or thrombus noted. With PEUU patching, fibroblast ingrowth occurred at 4 weeks, increasing with time. In contrast, expanded polytetrafluoroethylene patches exhibited no ingrowth and elicited local inflammation that moderated with time. CONCLUSIONS The PEUU patch demonstrated suitable mechanical properties and biocompatible characteristics in the right ventricular outflow tract replacement model, permitting cellular integration and endocardial endothelialization with minimal inflammation. Future application of this material as a cardiovascular scaffold seems promising.