A rate adaptive cardiac rhythm management device in which the pacing rate is adjusted in accordance with changes in the patient's minute ventilation. An adaptive four-pole elliptic digital filter, preferably implemented in software, functions to attenuate any signal components due to cardiac activity...http://www.google.com/patents/US5318597?utm_source=gb-gplus-sharePatent US5318597 - Rate adaptive cardiac rhythm management device control algorithm using trans-thoracic ventilation
