Going Around Phase Defects: Reliable Phase Mapping for Realistic Data (Optical Mapping Data)

This repository contains optical mapping data of ventricular fibrillation (VF) acquired from an isolated rat heart. The dataset was analyzed and presented in the paper: Going Around Phase Defects: Reliable Phase Mapping for Realistic Data. The data correspond to a single experimental case with maximally increased gap junction coupling achieved by administration of 80 nM rotigaptide. This condition was chosen to test the proposed phase-mapping methods under stable rotor dynamics. A Sprague–Dawley rat (250–300 g, 9–12 weeks old) heart was explanted and perfused ex vivo using a Langendorff setup with Krebs–Henseleit buffer maintained at 37 ± 0.5 °C and pH 7.35 ± 0.05. After 15 minutes of stabilization, the voltage-sensitive dye RH237 (40 µL, 5 mg/mL in DMSO) and the excitation–contraction uncoupler blebbistatin (30 µM loading, then 10 µM maintenance) were added. Gap junction coupling was enhanced by 80 nM rotigaptide. Ventricular fibrillation was induced electrically at the base of the left ventricle (MicroPace, USA) and sustained using pinacidil (30 µM). Optical mapping was performed using RH237 excitation at 530 nm. Emitted fluorescence was recorded with high-resolution CMOS cameras at a sampling rate of 1 kHz, with a spatial resolution of 128 × 80 pixels and a pixel size of approximately 100–125 µm. Data preprocessing was performed in MATLAB and included background subtraction, 3 × 3 spatial binning, low-pass filtering using a 50th-order FIR filter with a cutoff frequency of 100 Hz, and drift removal using a 100 ms sliding window. Additional details on the signal processing pipeline are described in Laughner et al. (2012)