An implantable cardiac device that is adapted to periodically measure a body parameter, such as transthoracic impedance, at time periods selected so that the body parameter is primarily indicative of the respiration of the patient. In this way, a ventilation parameter, such as minute ventilation, can...http://www.google.de/patents/US6449509?utm_source=gb-gplus-sharePatent US6449509 - Implantable stimulation device having synchronous sampling for a respiration sensor
