Figure 1.

Cardiac electrical excitation wave pattern and conversion into corresponding phase map for the localization of rotor core positions or phase singularities (PS). (A) Simulated electric spiral wave chaos pattern represented by transmembrane potential V ∈ [0, 1] (n.u., normalized units) and corresponding phase pattern with phase angle ϕ ∈ [−π, π]. (B) Time-series data showing a series of action potentials V(t) and their representation as a phase signal ϕ(t) computed using the Hilbert transform. (C) Classical phase singularity (PS) developed by Iyer and Gray (2001) using a circular integral (2×2 kernel) for the localization of spiral cores. Here the method is used to generate PS training data for deep learning-based PS detection (see Figure 2). Detailed field of view of region highlighted by black box in (A).