Electrical and structural remodeling disrupt atrial electrical conduction, leading to atrial fibrillation (AF). Epicardially delivered conductive biomaterial patches can effectively transmit electrical signals and potentially diminish AF. However, given the progressive nature of AF development, continuous and noninvasive monitoring is essential for assessing the therapeutic efficacy of these patches over time. In this study, superparamagnetic iron oxide nanoparticles (SPIO NPs) are synthesized and used to label a bio-conductive patch made of poly-3-amino-4-methoxybenzoic acid (PAMB) conjugated to gelatin (PAMBG-NP). Incorporating SPIO NPs does not alter the mechanical, electrical, or biocompatible properties of PAMBG. PAMBG-NP restores conduction velocity, suppresses rotor generation, and prevents re-entry currents, thereby relieving AF burden in an in vitro pacing model. In vivo, a bell-shaped PAMBG-NP patch is applied to the right and left atria of KCNE1 knockout mice. Compared to its Gelatin-NP counterpart, PAMBG-NP significantly reduces AF duration and enhances post-AF recovery over a 60-day period. Furthermore, magnetic resonance imaging indicates that PAMBG-NP degrades more slowly than Gelatin-NP, along with having a reduced incidence of AF in PAMBG-NP-treated animals. Therefore, incorporating SPIO NPs into PAMBG enables real-time, in vivo monitoring, potentially facilitating the noninvasive evaluation of its therapeutic efficacy.
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