Patent ID: 6961613

Claim:
An implantable heart stimulating device comprising: a first pacing circuit adapted for connection to a first pacing electrode, adapted for positioning for interaction with a first ventricle of a heart, to deliver signals from the first pacing circuit to pace the first ventricle; a first sensing circuit adapted for connection to a first sensing electrode, adapted to be positioned for interaction with the first ventricle to supply signals to the first sensing circuit for sensing the first ventricle; a second pacing circuit adapted for connection to a second pacing electrode, adapted to be positioned to interact with a second ventricle of the heart, to deliver signals from the second pacing circuit to the second ventricle to pace the second ventricle; a second sensing circuit adapted for connection to a second sensing electrode, adapted to be positioned to interact with the second ventricle, to supply signals to the second sensing circuit to sense the second ventricle; a control circuit operable with time cycles corresponding to normal cardiac cycles, said control circuit being connected to said first pacing circuit and to said first sensing circuit to detect an evoked response to a pacing pulse delivered by said first pacing circuit by sensing, via said first sensing circuit, within a first time interval following said pacing pulse delivered by said first pacing circuit; said control circuit being connected to said second pacing circuit and said second sensing circuit for detecting an evoked response to a pacing pulse delivered by said second pacing circuit by sensing, via said second sensing circuit, within a second time interval following the pacing pulse delivered by said second pacing circuit; said control circuit, within one of said time cycles, causing said first and second pacing circuits to respectively deliver pacing pulses with a time gap therebetween, said pacing pulse delivered by said second pacing circuit falling substantially within said first time interval and thereby masking detection of an evoked response to a pacing pulse delivered by the first pacing circuit; and said control circuit spontaneously temporarily modifying delivery of the pacing pulses by said second pacing circuit so that, during at least one of said time cycles, no pacing pulse is delivered by said second pacing circuit during said first time interval.