Figure 4
Membrane potential traces from two distinct locations (depicted in Fig.3) in the tissue (left side) and its recurrence plots (right side). (A) A spiral wave anchored to a highly fibrotic region resulting in sustained re-entry. The spiral wave regularly stimulates the tissue at both sites. This phenomenon is manifested in RPs by long uninterupted diagonal lines. On these diagonals there are small squares created by the plateau phase. (B) The regular meandering of the spiral wave manifests by repeating patterns in the time series. Due to the long period, uninterrupted lines are not visible in the RP as in the case of an anchored spiral wave. (C) Tissue experiencing fibrillatory activation. The time series created by this activation does not contain any regular patterns. Therefore long uninterrupted lines are not visible in the RP. The large black square visible in the right RP is due to the membrane potential remaining in the resting state between 200 and 400 ms (in the right time series). (D) Spiral wave anchored to a scar region (bottom right), that breaks up into wavelets away from the main rotor. This propagation manifests irregular patterns (left time series) and regular AP waveforms (right time series). However, the surrounding fibrillatory activation disrupts the regularity of these waveforms. As a result, the diagonal lines are interrupted.
