Supplements revised_RH-00414-2025.docx

Arrhythmias in calcium transients are easy to detect by human perception. However, quantifying these arrhythmias in a computer-readable manner remains challenging. To address this, we developed Arrhythpy, an automated tool that measures arrhythmias in iPSC-derived cardiomyocytes by analyzing Ca2+ transients. Unlike other tools, Arrhythpy directly evaluates arrhythmia levels. It effectively monitors arrhythmias in healthy and diseased iPSC-CMs, including dilated cardiomyopathy and Takotsubo Syndrome. Arrhythpy's flexible framework suits varied cell types and measurement techniques.