The fate of the fresh autologous pericardium after right ventricular outflow tract reconstruction

Introduction: The autologous pericardium, treated or fresh, is used in reconstructive cardiovascular surgery. We aimed to describe the features of fresh pericardium utilized in right ventricular outflow tract (RVOT) reconstruction, years after the initial surgery. Methods: This cross-sectional study was performed on 72 patients (65.3% male, mean age =18.68 ± 9.63 y) with a history of RVOT reconstruction with the fresh autologous pericardium who underwent reoperation. During the surgery, a 1 × 1 cm sample was cut from the previous pericardial patch, and hematoxylin and eosin (H & E), Masson's trichrome, and immunohistochemistry (IHC) staining was conducted. All the stained slides were evaluated,and the descriptive results were explained. Results: The mean follow-up duration was 13.48 ± 7.38 years. In preoperative evaluations,53 (73.6%) patients exhibited no RVOT dilatation, 17 (23.6%) showed mild RVOT dilatation,and 2 (2.8%) had RVOT aneurysms. The H & E staining revealed no calcification in 80.55%(58/72), mild calcification in 9.72% (7/72), and moderate calcification in 9.72% (7/72) of the total samples. None of the specimens demonstrated a marked calcification. All the samples were positive for CD31, CD34, smooth muscle alpha-actin, and von Willebrand factor in IHC. In Masson's trichrome staining, on average, 64.74% (±18.61) of the tissue sections contained collagen fibers. Conclusion: The fresh autologous pericardium, utilized for RVOT reconstruction, showed viability, growth potential, positivity for endothelial cell markers, vascular differentiation,insignificant calcification, and no stenosis at long-term follow-up. We would, therefore, suggest it as a suitable choice for such reconstructive operations. Moreover, its usage during total correction of tetralogy of Fallot could be safe, feasible, and durable.