# Rotor Location During Atrial Fibrillation: A Framework Based on Data Fusion and Information Quality
## 3 Results  
Figure 10 shows the maps generated from the EGMs and affected by the loss of samples (Figure 10a), spikes (Figure 10b), and PLI (Figure 10c). Figure 11a depicts maps affected by different configurations of simultaneous perturbations, including loss of samples, spikes, and PLI. Figure 11b presents the maps with a loss of resolution of 97.3% and affected by different levels of loss of samples, spikes, and PLI. These maps were analyzed by EGM experts to establish the best maps (features least affected by noise) to identify ablation areas. The analysis is detailed below. 1. EGM maps affected by the loss of samples: Mean maps reveal the rotor tip area. The rest of the tissue has low values, demonstrating regular activity. A similar performance was observed for the ApEn map with a loss of samples \(=\) 0.01 and the SampEn map with a loss of samples \(=\) 0.01. The ApEn and SampEn maps show a high-value area where the rotor tip is located. Intermediate values appear in regions of regular activity where low values are expected. In addition, ApEn and SampEn maps present the characteristic star shape corresponding to the slight migration of the rotor. The worst maps are generated by the STD and ShEn features, which exhibit high values at the edges and intermediate values in regions of regular activity. Figure 10: Statistical feature maps affected by different levels of perturbations. **(a)** Loss of samples, **(b)** spikes, and **(c)** PLI. The color scale depicts the normalized values of statistics estimations. Figure 9: Experimental procedure before testing the proposed model: a general mapping of the proposed framework is performed; then, techniques and IQ criteria (with their metrics) are selected for each level. Finally, databases are constructed to validate the proposed framework. * EGM maps affected by spikes: The best outcomes are observed for the mean map, followed by the ApEn map, and the SampEn map affected by spikes at 0.01, 0.05, and 0.1. The STD and ShEn maps do not yield good results. * EGM maps affected by PLI: All mean maps are useful for rotor detection, as they allow the identification of a very specific rotor tip area, while low amplitudes are observed in the rest of the tissue, where regular electrical activity occurs. The first two SampEn maps could be useful, as they reveal the characteristic star shape of the slight migration of the rotor tip. However, intermediate values appear in regions of regular activity, where low values would be expected. The ApEn and ShEn maps exhibit issues with high values at the borders. * EGM maps simultaneously affected by different configurations of loss of samples, spikes, and PLI (Figure 11): The mean map performs well under the following noise configurations 0.01/0.01/15 dB, 0.1/0.01/15 dB, and 0.01/0.01/15 dB. The remaining mean maps are similar. The SampEn maps with noise configurations of 0.01/0.01/15 dB and 0.01/0.1/15 dB to allow the identification of the rotor tip. The ApEn maps with noise configurations of 0.01/0.1/15 dB and 0.1/0.01/15 dB exhibit a reduced area of high amplitudes. The other maps are not suitable for identifying ablation areas. For each set of noise-contaminated signals (i.e., level 0), the following quality measures were calculated: accuracy--spikes, accuracy--PLI, data--amount, and completeness. The absolute values of the Pearson correlations between pairs of quality criteria from level 0 are presented in Table 3. High correlations are observed between the following pairs: accuracy--spikes and spikes--real, accuracy--PLI and data--amount, and completeness and loss of samples.