A method and device for sensing cardiac activity that includes a first plurality of electrodes forming a first electrode configuration to sense cardiac activity, a second plurality of electrodes forming a second electrode configuration to sense cardiac activity, and a third plurality of electrodes to deliver a stimulation pulse in response to the sensed cardiac activity. A microprocessor determines whether an escape interval associated with the delivered stimulation pulse is less than a rate limit interval, and a control circuit switches from the first plurality of electrodes to the second plurality of electrodes in response to the escape interval being less than the rate limit interval.