Polypyrrole-Chitosan Hydrogel Functions as a Semi-conductive Bridge Within Fibrotic Matrix and Cardiac Tissue

Myocardial infarction(MI) results in myocardial fibrosis leading to cardiac arrhythmia. We previously developed conductive biomaterial, polypyrrole-chitosan(PPY:CHI), which can prevent arrhythmias after MI. However, mechanism is unknown. I hypothesized that PPY:CHI reduces myocardial fibrotic tissue(FT) resistance to enhance myocardial conduction. To investigate electrical improvements of FT, PPY:CHI was added into Invitro and Ex-vivo FT matrix models. Three studies were performed to evaluate effect of PPY:CHI on fibrotic matrix, 1)impedance analysis using impedance spectroscopy; 2)electrical potential analysis using multi-electrode arrays(MEA), and 3)conduction velocity analysis using MEA. The research results showed 1)PPY:CHI reduced the impedance of the FT to a level like healthy myocardium; 2)PPY:CHI influenced the FT to transmit field potentials to a level like healthy myocardium; and 3)PPY:CHI influenced the FT to generate a velocity to a level like healthy myocardium. Addition of PPY:CHI to the FT models improved electrical conduction and transferred electrical potentials at a distance.M.A.S