No method is perfect when faced with detection of local activations in AF electrograms. In case of well defined local deflections, simple algorithms work. But when fractionation shows up, all methods fail, including expert-based visual inspection. However, even in case of high degree of fractionation, there is usually a “pulse” in the background that can be picked up – and serve as an estimator of underlying cycle length. One of the efficient methods for detecting such pulse is sinusoidal recomposition [1]. However, the methods requires base cycle length to start analysis. We propose to modify the method by applying method consecutively, using resulting mean AFCL as base value for subsequent iterations. Such approach starts from e.g. base value of 180 ms and iterates until stable mean AFCL is reached – usually after 2-3 iterations.

[1] Kuklik P, Zeemering S, Maesen B, Maessen J, Crijns HJ, Verheule S, et al. Reconstruction of instantaneous phase of unipolar atrial contact electrogram using a concept of sinusoidal recomposition and Hilbert transform. IEEE Trans Biomed Eng. 2015 Jan;62(1):296–302.