ECG data is analyzed by detecting points in the ECG data which represent ventricular activity measuring time intervals between each two consecutive points in the ECG data which represent ventricular activity and then within a set of such time intervals, evaluating the time intervals by computing at least one comparative dimension for at least one time interval subset. The time interval subset includes at least two time intervals, and the comparative dimension represents variations between the interval lengths between the time intervals of the time interval subset.
