Patent ID: 7151958

Claim:
A system, comprising: control circuitry where the control circuitry receives a first cardiac signal and a second cardiac signal sensed during a cardiac episode, where the first cardiac signal includes indications of depolarizations in a first cardiac area and the second cardiac signal includes indications of depolarizations in a second cardiac area, the control circuitry including: a first depolarization detector circuit to detect occurrence of primary depolarizations in the first cardiac signal; a second depolarization detector circuit to detect occurrence of auxiliary depolarizations in the second cardiac signal; a cardiac depolarization counting circuit coupled to the first depolarization detector circuit and the second depolarization detector circuit, where the cardiac depolarization counting circuit counts a first number (K) of auxiliary depolarizations occurring during a first portion of a first time interval surrounding each of one or more primary depolarizations of the primary depolarizations and counts a total number (N) of auxiliary depolarizations during the first time interval; and a microprocessor coupled to the cardiac depolarization counting circuit, where the microprocessor calculates K/N and determines whether the primary depolarizations and the auxiliary depolarizations in the cardiac episode are associated or disassociated based on K/N.