LAUSR

Over the past decade, tissue engineering strategies, mainly involving injectable hydrogels and epicardial biomaterial patches, have been pursued to treat myocardial infarction. However, only limited therapeutic efficacy is achieved with one single means. Here, a combined therapy approach is proposed, that is, the co-administration of a conductive hydrogel patch and injectable hydrogel to the infarcted myocardium. The self-adhesive conductive hydrogel patch is fabricated based on Fe3+-induced ionic coordination between dopamine-gelatin (GelDA) conjugates and dopamine-functionalized polypyrrole (DA-PPy), which forms a homogenous network. The injectable and cleavable hydrogel is formed in situ via Schiff base reaction between oxidized sodium hyaluronic acid (HA-CHO) and hydrazided hyaluronic acid (HHA). Compared with single mode system (SMS), injecting HA-CHO/HHA hydrogel intramyocardially followed by painting conductive GelDA/DA-PPy hydrogel patch on the heart surface results in more pronounced improvement of cardiac function in terms of echocardiographical, histological and angiogenic outcomes.