A method for providing a representation of the distribution, fluctuation and/or movement of electrical activity through heart tissue, said method comprising: obtaining an ECG of the heart comprising said tissue obtaining a model of the heart geometry obtaining a model of the torso geometry relating the measurements per electrode of the ECG to the heart and torso geometry and estimating the distribution, fluctuation and/or movement of electrical activity through heart tissue based upon a fastest route algorithm, shortest path algorithm and/or fast marching algorithm.