Topological charge-weighted method of identifying the phase singularity at low spatial resolution

Spiral waves in cardiac tissue are believed to be closely related to cardiac diseases such as arrhythmias. Accurately identifying the phase singularity (PS, the tip of a spiral wave) is important in electrophysiological studies of cardiac arrhythmias, for which various PS detection methods have been proposed. However, clinical data are typically low resolution, resulting in insufficient spatial information about spiral waves. Direct application of conventional PS detection methods to such data often results in false points. Here we find a characteristic in the PS distribution within low-resolution data: false points tend to appear in adjacent pairs, exhibiting opposite chirality. Based on this noteworthy finding, we propose the topological charge-weighted method, which is suitable for a single spiral wave system within low-resolution data. This method calculates a weighted PS and then generates a spatial continuous PS trajectory, reducing PS-detecting error rates while improving localization accuracy.