Activation Recovery Times

This workgroup aims to compare different post-processing methods to detect the time of electrical activation and/or recovery of local cardiac tissue from extracellular potentials or transmembrane voltages. We want to evaluate the performance of these methods by applying them to several datasets for which a ground truth is available. Finally, we aim to come to a conclusion, which method works best under which circumstances.

This effort is open to anyone. If you are interested, simply join the Google Group or send an email to

Group organizer: Steffen Schuler (

Members: Laura Bear, Dana Brooks, Matthijs Cluitmans, Önder Nazım Onak, Jake Bergquist

Intermediate results were presented at CinC 2019 – see paper or slides.

Simulations show that activation times estimated from reconstructions using 2nd order Tikhonov largely depend on the source model and the estimation method. For physiological cases, the best results could be obtained for transmembrane voltages and spatio-temporal estimation methods. Extracellular potentials are particularly prone to line of block artifacts near the junction of the septum and the outer wall. Purely temporal methods are less robust to noise in reconstructions.

Recently, we added pathological cases including real lines of block and scar patches. While these abnormalities can be recovered by purely temporal estimation methods, most spatio-temporal methods blur out these details by default. Appropriate adjustments to spatio-temporal methods are required to yield a robust method still sensitive to spatial details.