Bioinspired balloon catheter integrated with stretchable "flounder" electrodes under high voltage for uniform pulsed field ablation.

Atrial fibrillation leads to severe diseases such as heart failure and strokes. While catheter ablation is prevalent for the treatment, existing techniques hardly can achieve both tissue selectivity and ablation uniformity. Here, we propose a bioinspired strategy for balloon-based pulsed field ablation (PFA) systems based on "flounder" electrodes. Inspired by a flounder skeleton and citrus peels, the microfabricated electrodes are ultrathin, stretchable, and have a scattered configuration, withstanding large balloon deformation (87% compression), high voltage (1200 volts), and owning exceptional tissue conformability (720° twists). Mechanical-electrical coupled stimulation optimizes balloon electrodes with hemispherical electric field uniformity. A water lily-inspired transfer printing method enables one-step integration of multielectrodes with the balloon. A comprehensive PFA system is complemented, achieving ablation depths of 3.8 millimeters (potato), 3.1 millimeters (rabbit), and 2.3 millimeters (swine) with good uniformity and electrophysiological isolation. These results shed light on the quantitative design of PFA systems, with high potential for more precise, safe, and effective catheter ablation therapies.