Pericardial substitutes: delayed reexploration and findings.

Four patients' experience with two varieties of pericardial substitutes has been evaluated. Two patients received glutaraldehyde-preserved, formalin-fixed bovine bioprosthetic pericardial substitutes. These were associated with dense prosthesis-to-epicardium adhesions and the formation of a thick gelatinous peel. Two other patients received glutaraldehyde-preserved, ethanol-fixed bovine bioprosthetic pericardial substitutes. One patient had minimal prosthesis-to-epicardium adhesions, and the remaining patient demonstrated moderate prosthesis-to-epicardium adhesions with giant-cell and lymphocyte fibrosis. In all patients prosthesis-to-sternum adhesions were minimal. These observations suggest that careful washing is essential in all bioprosthetic implants to eliminate residual preservatives and fixatives. In addition, preservation in ethanol is associated with less prosthesis-epicardium reaction than is formalin preservation. Both products are successful in easing reentry, and no episode of infection has been associated with either prosthesis.