Soft and Adhesive Cardiac Patch for Electrophysiological and Contraction Measurement

Epicardial patches have been developed for real-time monitoring of the normal electrophysiological activities of the heart. However, the modulus of most patches is much higher than that of the heart, which can potentially be stripped from cardio surface and impose limitations on cardiac function. Here, an ultrasoft and adhesive cardiac patch is proposed to achieve high conformability to the beating heart surface owning to the sophisticated multi-material assembly process of each ultrathin and soft layer, resulting low Young's modulus close to that of the heart (∼ 65 kPa) and favorable tissue-adhesion properties (∼ 27 N m^-1) due to the hydrogen bond network provided by tannic acid and the covalent binding of carboxyl groups to amino groups. In addition, this patch can not only record the electrophysiological activities of the epicardium, but also measure contraction force of the myocardium, which provides a new monitoring perspective for the diagnosis of heart diseases. Therefore, it is believed that this epicardial electronic patch has great potential in fields such as ischemic heart disease.