The temporal behavior and consistency of bipolar atrial electrograms in human persistent atrial fibrillation

Figures

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  Fig. 1. a Different segment lengths exported from NavX to investigate the temporal consistency of AEG fractionation. The maximum AEG length that can be exported from NavX is 8 s, and smaller segments are exported as portions of the original 8 s. b The 8-s segments were divided in three consecutive 2.5-s segments, as illustrated in b, accordingly: 0 to 2.5 s; 2.5 to 5 s; 5 to 7.5 s

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  Fig. 2. Illustration of the different types of AEGs found when analyzing the consecutive AEG segments. Stable CFAEs (upper trace) are AEGs with ICL ≥ 4 in all assessed segments (upper trace). Stable non-CFAEs (middle trace) are AEGs with ICL < 4 in all assessed segments. Unstable AEG (lower trace) are AEGs with ICL varying to/from ICL ≥ 4 to ICL < 4 within the assessed segments

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  Fig. 3. The resultant LA maps based on the three consecutive AEG segments with 2.5-s duration each for one patient as measured by the ICL (upper), the ACI (middle), and the SCI (bottom). The location of the AEGs classified as stable CFAE, stable non-CFAE, and unstable shown in Fig. 2 are marked in the ICL map

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  Fig. 4. The temporal behavior of three consecutive AEGs segments with 2.5-s duration each. a The 8-s segments were divided in three consecutive 2.5-s length segments. The ICL was measured in each segment and classified whether as fractionated or nonfractionated. The AEGs that remained fractionated, remained nonfractionated, and changed classification were assessed between segments. b All segments were mutually compared. In each case, an AEG was considered “stable CFAE” if the assessed segments had ICL ≥ 4; an AEG was considered “stable non-CFAE” if the assessed segments had ICL < 4; or an AEG was considered “unstable” if the AEG changed from fractionated to nonfractionated or vice versa within the assessed segments. The percentage of “stable CFAE,” “stable non-CFAE,” and “unstable AEG” in each segment was calculated. c The temporal decay of stable AEGs was assessed. In the first 2.5-s segment, all AEGs were considered stable. On segment 2, a total of 151 AEGs were classified as unstable. On the last segment, additional 62 AEGs changed their classification. The exponential best fit with a time constant (τ) of 2.8 s. d The regional occurrence of the different types of AEGs normalized by…

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  Fig. 5. a The ICL, ACI, and SCI measured with 2.5, 5, and 8 s. b Bland-Altman plots for ICL, ACI, and SCI measured with 2.5, 5, and 8 s. ****P < 0.0001; ***P < 0.001

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  Fig. 6. The resultant LA maps based on the different segment lengths (2.5, 5, and 8 s) for one patient as measured by ICL (upper), ACI (middle), and SCI (bottom)