Figure 5
Example of calculated tissue maps (with the size of \(4\times {4}\,{\text{cm}}\)) depicting the spatial distribution of selected RQA measures. Rows: A) anchored rotation, B) traveling rotor, C) fibrillation, D) fibrillation with anchored rotation. Columns: RQA measures 1) RATIO, 2) LAM, 3) ENTR, and 4) DET. A pattern indicating the type of analyzed propagation can be found in all maps. In anchored rotation (A), a spiral created by the rotational movement of the AP can be seen. Three spirals formed by the meandering rotor can be found (B) (in each spiral, the AP re-entries the tissue). The region around which the AP rotates is highlighted in the middle of these spirals. Fibrilatory activation (C) is manifested in maps by irregular, chaotically distributed shapes. Fibrillation associated with anchored rotation (D) in the maps (especially in measure RATIO) shows larger contiguous regions created by regular propagation made by anchored rotation. If we compare the mean values of individual RQA measures, we can see a lower mean value of RATIO (Ratio between DET and REC) for anchored rotation (see boxplots in Fig. 6). This phenomenon is caused by the higher value of the RR measure due to diagonal lines manifesting periodic motion in RP (see Fig. 4). There is also a high mean value for measure LAM (percentage of vertical lines in RP). A regular resting phase causes this phenomenon during anchored rotation (manifesting as black squares in RP). This phase can also be partially found in the meandering rotor, as its average value in the tissue is the second highest (see Fig. 6). The average value of the ENTR measure is the highest for anchored rotation. ENTR achieves high values, as RPs of this type of propagation are the most complex (due to diagonal lines and their connected patterns). The Mean value of the DET measure is highest for anchored rotation due to the repetitive nature of this propagation. The irregularity of fibrillatory activation is reflected in the lowest value of this measure for all the types of analyzed propagation.
