A self-locking conductive cardiac patch for immediate electrical integration with infarcted rat myocardium

Myocardial infarction (MI) is the leading cause of human death. Conductive patches have emerged as a promising alternative for MI repair. However, due to the epicardium and the scar tissue blocking the electrical connection between the patch and the myocardium, the immediate and effective electrical integration of the patch with the host myocardium remains a great challenge. Here, we report a conductive barbed microneedle-integrated conductive patch (CBMN-CP). The microneedle can not only self-anchor robustly to the myocardium, but also penetrate the epicardium into the inner myocardium enabling patch to bridge non-infarcted myocardium across the infarcted area immediately and to re-establish the electrical pathways in the infarcted myocardium. The rat MI model experiments demonstrated CBMN-CP significantly improved early cardiac function on day 3 post-infarction compared with traditional conductive patch. CBMN-CP enhanced myocardial repair efficacy by re-establishing intercellular electrical connections, promoting angiogenesis and regulating inflammatory responses. RNA sequencing showed that CBMN-CP mediated cardiac functions mainly through regulating early cardiac conduction and calcium handling-related gene expressions. Overall, the strategy of providing an immediate electrical integration through CBMN-CP demonstrated promising results and would be valuable in practical applications.