Detection of patient's position and activity status using 3D accelerometer-based position sensor

摘要

An implantable cardiac stimulation device is equipped with an accelerometer-based sensor to sense a patient's movement and produce a vertical acceleration component indicative of a patient's acceleration in a vertical direction. A vertical velocity component is computed from the vertical acceleration component. The device further includes a minute ventilation sensor to sense minute ventilation of the patient. Coupled to the various sensors is a processor that is programmed to determine a patient's position and activity status, such as whether the patient is ascending/descending stairs or is sitting up from a lying position, based on the vertical velocity and minute ventilation data. The patient's status dictates whether to administer cardiac pacing therapy to the patient and the kind of therapy to be applied.