Reservoir Microneedle Patch Mitigates Postsurgical Atrial Fibrillation

Oral amiodarone for 3–6 months is commonly required for the prevention and treatment of atrial fibrillation (AF) after surgical ablation of refractory AF. However, clinical data show that oral administration is likely to cause systemic toxicity, especially pulmonary fibrosis. Here, a new strategy is described for the treatment and prevention of postsurgical AF via the epicardial application of a monolithic reservoir microneedle device. These findings demonstrate that this strategy enables a sustained transport of amiodarone directly to the atrium, thereby maximizing therapeutic efficacy and minimizing systemic drug distribution. Notably, a significantly reduced drug dosage (only one dose of 6.3 mg for reservoir MNs versus a daily dose of ≈10 mg for oral administration) achieves therapeutic efficacy over a long period of 24 weeks in a rat AF model, circumventing the risks of pulmonary fibrosis associated with oral administration. This device can serve as a promising alternative to oral amiodarone, providing a robust therapeutic strategy for the prevention and treatment of postsurgical AF is antipicated.