Bi-layered polyurethane nanofiber patches with asymmetrical surface prevent postoperative adhesion and enhance cardiac repair

The adhesion between heart and chest post-operation raises a significant challenge for the application of cardiac patches due to its severe influences on the recovery of heart function and increased risk of re-treatment. Anabatic inflammatory response and increased oxidative stress aggravate the damage to heart functions. Herein, a multifunctional cardiac patch was manufactured by successive electrospinning of two types of novel seleniumcontaining polyurethanes (PU), followed by click grafting of poly (ethylene glycol) (PEG) molecules on the top layer. This patch possessed dual-functions of postoperative anti-adhesion and anti-oxidative stress for efficient therapy post myocardial infarction (MI). The high redox reactivity of diselenium bonds were introduced into the main chains of PU, which reduced the level of reactive oxygen species (ROS) and modulated the inflammatory environment, alleviating the synechia formation simultaneously. The cardiac patch could effectively resist fibroblast adhesion, regulate the expression of vinculin and tissue-type plasminogen activator (t-PA), and inhibit the synechia formation. Meanwhile, it also restored significantly the heart function post MI by decreasing the local inflammation, facilitating less collagen formation, and improving cell signal transduction and angiogenesis. Collectively, this novel patch achieved anti-adhesion and therapeutic effect synergistically, bringing advancement in cardiac patch design and potential for translation of medicinal devices.