INDUCING PREMATURE ATRIAL CONTRACTIONS FOR THE PURPOSE OF MONITORING AUTONOMIC TONE RISK OF SUDDEN CARDIAC DEATH AND ISCHEMIC EVENTS

• US 20090281440A1
• Filed: 07/16/2009
• Published: 11/12/2009
• Est. Priority Date: 07/13/2005
• Status: Active Grant

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Inventors: Falkenberg, Eric, Farazi, Taraneh Ghaffari
• Granted Patent: US 8,548,589 B2
• Time in Patent Office: Days
• US Class Current: 600/510
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/02405 Determining heart rate variability
• CPC Class Codes: A61B 5/36 Detecting PQ interval, PR interval or QT interval
• CPC Class Codes: A61B 5/364 Detecting abnormal ECG interval, e.g. extrasystoles, ectopic heartbeats
• CPC Class Codes: A61B 5/4035 Evaluating the autonomic nervous system
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
• CPC Class Codes: A61N 1/365 controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371
• CPC Class Codes: A61N 1/36585 controlled by two or more physical parameters
• CPC Class Codes: A61N 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment

Abstract

Implantable systems, and methods for use therein, perform at least one of a cardiac assessment and an autonomic assessment. Premature atrial contractions (PACs) are induced to thereby cause corresponding premature contractions in the ventricles. Short-term fluctuations in cardiac intervals, that follow the premature contractions in the ventricles caused by the induced PACs, are monitored. At least one of a cardiac assessment and an autonomic assessment is performed based on the monitored fluctuations in cardiac intervals that follow the premature contractions in the ventricles caused by the induced PACs. This can include assessing a patient'"'"'s risk of sudden cardiac death (SCD), assessing a patient'"'"'s autonomic tone and/or detecting myocardial ischemic events based on the monitored fluctuations in cardiac intervals that follow the premature contractions in the ventricles caused by the induced PACs.

Claims

1. For use with an implantable system, a method of performing at least one of a cardiac assessment and an autonomic assessment, comprising:

(a) inducing premature atrial contractions (PACs) to thereby cause a corresponding premature contractions in the ventricles;

(b) monitoring morphology of a signal that is indicative of cardiac intervals that follow the premature contractions of the ventricles caused by the induced PACs; and

(c) performing at least one of a cardiac assessment and an autonomic assessment, based on the monitored morphology of the signal that is indicative of cardiac intervals that follow the premature contractions of the ventricles caused by the induced PACs.

2. The method of claim 1, wherein step (c) comprises assessing a patient'"'"'s risk of sudden cardiac death (SCD) based on the monitored morphology of the signal that is indicative of cardiac intervals that follow the premature contractions of the ventricles caused by the induced PACs.

3. The method of claim 1, wherein step (c) comprises assessing a patient'"'"'s autonomic tone based on the monitored morphology of the signal that is indicative of cardiac intervals that follow the premature contractions of the ventricles caused by the induced PACs.

4. The method of claim 1, wherein step (c) comprises detecting a myocardial ischemic event based on the monitored morphology of the signal that is indicative of cardiac intervals that follow the premature contractions of the ventricles caused by the induced PACs.

5. The method of claim 4, wherein step (c) includes comparing the monitored morphology to a baseline morphology, and detecting a myocardial ischemic event when the monitored morphology differs from the baseline morphology by more than a specified degree.

6. An implantable system for performing at least one of a cardiac assessment and an autonomic assessment, comprising:

means for inducing premature atrial contractions (PACs) to thereby cause corresponding premature contractions in the ventricles;

means for monitoring morphology of a signal that is indicative of cardiac intervals that follow the premature contractions of the ventricles caused by the induced PACs; and

means for performing at least one of a cardiac assessment and an autonomic assessment, based on the monitored morphology of the signal that is indicative of cardiac intervals that follow the premature contractions of the ventricles caused by the induced PACs.

7. The system of claim 6, wherein the means for performing assesses a patient'"'"'s risk of sudden cardiac death (SCD) based on the monitored morphology of the signal that is indicative of cardiac intervals that follow the premature contractions of the ventricles caused by the induced PACs.

8. The system of claim 6 wherein the means for performing assesses a patient'"'"'s autonomic tone based on the monitored morphology of the signal that is indicative of cardiac intervals that follow the premature contractions of the ventricles caused by the induced PACs.

9. The system of claim 6, wherein the means for performing detects a myocardial ischemic event based on the monitored morphology of the signal that is indicative of cardiac intervals that follow the premature contractions of the ventricles caused by the induced PACs.

10. The system of claim 6, wherein the means for performing compares the monitored morphology to a baseline morphology, and detects a myocardial ischemic event when the monitored morphology differs from the baseline morphology by more than a specified degree.

11. For use with an implantable system, a method of performing at least one of a cardiac assessment and an autonomic assessment, comprising:

(a) inducing a premature atrial contraction (PAC) that is followed, after an AV delay, by delivery of a ventricular pacing pulse;

(b) monitoring short-term fluctuations in cardiac intervals that follow the delivery of the ventricular pacing pulse that followed the induced PAC; and

(c) performing at least one of a cardiac assessment and an autonomic assessment, based on the monitored fluctuations in cardiac intervals that follow the delivery of the ventricular pacing pulse that followed the induced PAC.