A cardiac stimulating device

摘要

An implantable cardiac stimulating device has a control circuit which varies the rate of stimulation pulses up to a maximum pacing rate. A sensor senses at least one evoked response parameter to a delivered stimulation pulse, and the control circuit compares a time gap between the stimulation pulse and its associated evoked response parameter. The control circuit lowers the maximum pacing rate if the time gap does not increase as the pulse rate is increased.