Monitoring heart disease using implantable sensors

Abstract

Specific embodiments of the present invention determine a range of a physiologic property, for each of a plurality of periods of time, and monitor changes in the patient's heart disease based on changes in the range. Other embodiments determine a minimum of a physiologic property, for each of a plurality of periods of time, and monitor changes in the patient's heart disease based on changes in the minimum. Still other embodiments determine a maximum of the physiologic property, for each of a plurality of periods of time, and monitor changes in the patient's heart disease based on changes in the maximum.

What is claimed is: 
     
         1 . A system for monitoring a patient's heart disease, comprising:
 an implantable sensor to measure a physiologic property;   a heart disease monitor to monitor the physiologic property when the patient's heart is not stressed, to monitor the physiologic property when the patient's heart is stressed, and to determine a range of the physiologic property for each of a plurality of periods of time;   wherein the monitor monitors changes in the patient's heart disease based on how the range of the physiologic property changes over time.   
     
     
         2 . The system of  claim 1  wherein the heart disease monitor determines whether the patient's heart disease has worsened, improved, or stayed relatively the same, based on the how the range of the physiologic property changes over time. 
     
     
         3 . The system of  claim 1 , further comprising an activity sensor to determine when the patient's heart is stressed and when the patient's heart is not stressed. 
     
     
         4 . The system of  claim 1 , wherein the system monitors heart rate to determine when the patient's heart is stressed and when the patient's heart is not stressed. 
     
     
         5 . A system for monitoring a patient's heart disease, comprising:
 an implantable sensor to measure a physiologic property; and   a heart disease monitor to monitor the physiologic property and to determine one of a minimum and maximum of the physiologic property for each of a plurality of periods of time;   wherein the monitor monitors changes in the patient's heart disease based on how the one of the minimum and maximum of the physiologic property changes over time.   
     
     
         6 . The system of  claim 5 , wherein the heart disease monitor:
 determines the minimum of the physiologic property for each of a plurality of periods of time; and   monitors changes in the patient's heart disease based on how the minimum of the physiologic property changes over time.   
     
     
         7 . The system of  claim 6 , further comprising:
 an activity sensor to monitor the patient's level of activity;   wherein the heart disease monitor determines the minimum of the physiologic property when the patient's level of activity, as determined using the activity sensor, is one of above or below a specified level.   
     
     
         8 . The system of  claim 5 , wherein the heart disease monitor:
 determines the maximum of the physiologic property for each of a plurality of periods of time; and   monitors changes in the patient's heart disease based on how the maximum of the physiologic property changes over time.