Detection of renal failure by cardiac implantable medical device

• US 20070038138A1
• Filed: 08/11/2005
• Published: 02/15/2007
• Est. Priority Date: 08/11/2005
• Status: Active Grant

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Inventors: Gill, Jong, Bornzin, Gene
• Granted Patent: US 7,529,580 B2
• Time in Patent Office: Days
• US Class Current: 600/513
• CPC Class Codes: A61B 5/201 Assessing renal or kidney functions
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61N 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371

Abstract

Morphological features within electrical cardiac signals are tracked and changes in features are monitored to detect renal failure. The morphological feature may be an interval between corresponding polarization events such as the interval between QRS-complexes and peaks of corresponding T-waves (QTmax interval); the interval between QRS-complexes and ends of corresponding T-waves (QTend interval); or the interval between P-waves and corresponding QRS-complexes (PR interval). The feature may also be the elevation of a cardiac signal segment between corresponding polarization events, such as QRS-complexes and corresponding T-waves (ST segment); a duration of a polarization event, such as a QRS-complex (QRS width); or an amplitude of a polarization event, such as a T-wave (T-wave amplitude). The change in the feature may comprise a decrease in QTmax intervals, a decrease in QTend intervals, a deviation in ST segment elevation, an increase in QRS width, an increase in PR interval or a deviation in T-wave amplitude.

Claims

1. A system for detecting renal failure comprising:

a tracking unit operative to track a morphological feature within electrical cardiac signals obtained using an implantable medical device; and

a renal failure detection unit operative to detect renal failure based at least in part on a change in the feature.

2. The system of claim 1 wherein the tracking unit is operative to track a plurality of morphological features and the detection unit is operative to detect renal failure based on changes in at least two of the features.

3. The system of claim 1 wherein the tracking unit is operative to track an interval between morphological features and the detection unit is operative to detect renal failure based a change in the interval.

4. The system of claim 1 wherein the tracking unit is operative to track an elevation of a morphological feature and the detection unit is operative to detect renal failure based a change in the elevation.

5. The system of claim 1 wherein the tracking unit is operative to track a duration of a morphological feature and the detection unit is operative to detect renal failure based a change in the duration.

6. The system of claim 1 wherein:

the morphological feature comprises any one of;

an interval between QRS-complexes and peaks of corresponding T-waves (QTmax interval), an interval between QRS-complexes and ends of corresponding T-waves (QTend interval), elevation of a segment of a cardiac signal between QRS-complexes and corresponding T-waves (ST segment), a duration of QRS-complexes (QRS width), an interval between P-waves and corresponding QRS-complexes (PR interval) and an amplitude of T-waves (T-wave amplitude); and

the change comprise a decrease in QTmax intervals, a decrease in QTend intervals, a deviation in ST segment elevation, an increase in QRS width, an increase in PR interval and a deviation in T-wave amplitude.

7. An implantable system for detecting renal failure comprising:

means for tracking a morphological feature within electrical cardiac signals; and

means for detecting renal failure based at least in part on a change in the feature.

8. The system of claim 7 wherein the means for tracking comprises means for tracking a plurality of morphological features.

9. The system of claim 8 wherein the means for detecting renal failure detects renal failure based on changes in at least two of the features.

10. The system of claim 7 wherein the means for tracking comprises means for tracking an interval between morphological features.

11. The system of claim 7 wherein the means for tracking comprises means for tracking an elevation of a morphological feature.

12. The system of claim 7 wherein the means for tracking comprises means for tracking a duration of a morphological feature.

13. An implantable medical system for detecting renal failure comprising:

at least one lead comprising an electrode configured for placement within a patient in electrical contact with the patient'"'"'s heart and operative to sense electrical cardiac signals;

an implantable medical device adapted to be connected to the at least one lead and comprising a tracking unit operative to track at least one morphological feature based on the sensed electrical cardiac signals; and

a renal failure detection unit operative to detect renal failure based at least in part on a change in the feature.

14. The system of claim 13 wherein the tracking unit is operative to track a plurality of morphological features.

15. The system of claim 14 wherein the renal failure detection unit is operative to detect renal failure based on changes in at least two of the features.

16. The system of claim 13 wherein the tracking unit is operative to track an interval between morphological features.

17. The system of claim 13 wherein the tracking unit is operative to track an elevation of a morphological feature.

18. The system of claim 13 wherein the tracking unit is operative to track a duration of a morphological feature.