Methods and systems that use implanted posture sensor to monitor left atrial pressure and/or inter-thoracic fluid volume

摘要

In specific embodiments, a method to monitor left atrial pressure and/or intra-thoracic fluid volume of a patient, comprises (a) monitoring posture of the patient using a posture sensor implanted within the patient, and (b) using portions of an impedance signal, obtained using implanted electrodes, to monitor the left atrial pressure and/or intra-thoracic fluid volume of the patient. Each portion of the impedance signal used to monitor the left atrial pressure and/or intra-thoracic fluid volume of the patient corresponds to a period after which the patient has maintained a predetermined posture for at least a predetermined period of time, and during which the patient has remained in the predetermined posture.

主权项

1. A method to monitor left atrial pressure (LAP) of a patient comprising:
(a) storing data indicative of an impedance signal for at least a first specified period of time, obtained using implanted electrodes, and a corresponding posture of the patient, as determined using an implanted posture sensor; (b) identifying, based on the stored data, one or more snapshots of the impedance signal where the patient is in a predetermined posture and where prior to each snapshot the patient substantially maintained the predetermined posture for at least a second specified period of time, and during the snapshot the patient maintained the predetermined posture for at least a third specified period of time; (c) calculating, for each of the identified one or more snapshots of the impedance signal, a separate zLAP value indicative of the patient's left atrial pressure (LAP) while the patient is in the predetermined posture; (d) identifying an undesirably abnormal change in the patient's left atrial pressure (LAP) in response to at least one of
(d.1) detecting a change in the calculated zLAP values by a predefined amount, or(d.2) detecting a trend in the calculated zLAP values that are symptomatic of organ damage and/or failure; and (e) one or both of triggering an alert or adjusting therapy administered to the patient in response to identifying the abnormality.