A functional cardiac patch with "gas and ion" dual-effect intervention for reconstructing blood microcirculation in myocardial infarction repair.

Postinfarction revascularization is critical for repairing the infarcted myocardium and for stopping disease progression. Considering the limitations of surgical intervention, engineered cardiac patches (ECPs) are more effective in establishing rich blood supply networks. For efficacy, ECPs should promote the formation of more mature blood vessels to improve microcirculatory dysfunction and mitigate hypoxia-induced apoptosis. Developing collateral circulation between infarcted myocardium and ECPs for restoring blood perfusion remains a challenge. Here, an ion-conductive composite ECPs (GMA@OSM) with powerful angiogenesis-promoting ability was constructed. Based on dual-effect intervention of oxygen and strontium, the developed ECPs can promote the formation of high-density circulating microvascular network at the infarcted myocardium. In addition, the GMA@OSM possesses effective reactive oxygen species-scavenging capacity and can facilitate electrophysiological repair of myocardium with ionic conductivity. In vitro and in vivo studies indicate that the multifunctional GMA@OSM ECPs form well-developed collateral circulation with infarcted myocardium to protect cardiomyocytes and improve cardiac function. Overall, this study highlights the potential of a multifunctional platform for developing collateral circulation, which can lead to an effective therapeutic strategy for repairing myocardial infarction.