A system for analyzing cardiac electrophysiological signals includes an acquisition processor for acquiring signal data representing heart electrical activity over multiple heart cycles. An individual heart cycle comprises a signal portion between successive sequential R waves. A time interval detector uses a signal peak detector for detecting multiple successive time intervals including individual time intervals comprising a time interval between a first peak occurring in a first heart cycle and a second peak occurring in at least one of, (a) a successive sequential second heart cycle and (b) a third heart cycle successive and sequential to the second heart cycle. A data processor processes the multiple detected successive time intervals by, determining at least one interval parameter of, a mean, variance and standard deviation of the time intervals and generating an alert message in response to the interval parameter.
