Atorvastatin attenuates post-implant tissue degeneration of cardiac prosthetic valve bovine pericardial tissue in a subcutaneous animal model

Aims
The aim of our study was to examine the effects of statin therapy (atorvastatin) on post-implant structural changes of bovine pericardial tissue in a subcutaneous animal model.
Methods and results
Sixty male C57BL/6 mice underwent subcutaneous dorsal implantation of bovine pericardial fragments. Animals were randomized to treatment with atorvastatin (50 mg/kg) (statin group — SG) or to vehicle (control group — CG). After 1.5 months, all fragments were explanted and submitted to histopathological assessment (semi-quantitative analysis) to elucidate extent of inflammatory infiltrate, signs of tissue injury, or presence of microcalcification. Calcium determination of the implanted pericardial tissue was also performed by inductively coupled plasma mass spectrometry (ICP-MS) assessment.
ICP-MS analysis showed that pericardial fragments in SG had significantly (p < 0.01) less calcium content than CG (625 ± 142 vs. 962 ± 590 µg/g, respectively). Light microscopy showed marked inflammatory infiltrates and tissue injury of pericardial specimens in CG animals, whereas SG animals maintained a better preserved original pericardial structure.
Conclusions
Our findings indicate that atorvastatin significantly attenuates the post-implant structural degeneration of artificial valve bovine pericardial tissue in a subcutaneous animal model. Further observations are mandatory to assess the effects of statins on the implanted bioprosthetic valve tissue in the blood circulation.