Method and apparatus for identification of ischemic/infarcted regions and therapy optimization

• US 20080082135A1
• Filed: 10/02/2006
• Published: 04/03/2008
• Est. Priority Date: 10/02/2006
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Hartemink, Chris, Stucky, Michael J., Yu, Yinghong, Shuros, Allan C., Ding, Jiang, Arcot-Krishnamurthy, Shantha
• Granted Patent: US 8,219,210 B2
• Time in Patent Office: Days
• US Class Current: 607/9
• CPC Class Codes: A61B 5/02028 Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction
• 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 1/36585 controlled by two or more physical parameters
• CPC Class Codes: A61N 1/3682 with a variable atrioventricular delay
• CPC Class Codes: A61N 1/3684 for stimulating the heart at multiple sites of the ventricle or the atrium
• CPC Class Codes: A61N 1/36842 Multi-site stimulation in the same chamber
• CPC Class Codes: A61N 1/36843 Bi-ventricular stimulation
• CPC Class Codes: A61N 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371

Abstract

A method and apparatus is described for detecting and localizing areas of myocardial infarction or ischemia. By pacing sites in proximity to the infarcted or ischemic region with appropriately timed pacing pulses, the region is pre-excited in a manner that lessens the mechanical stress to which it is subjected, thus reducing the metabolic demand of the region and the stimulus for remodeling.

Claims

1. An implantable device, comprising:

a plurality of sensors adapted to be disposed near different myocardial regions;

sensing circuitry for receiving signals from the plurality of sensors;

a controller interfaced to the sensing circuitry that is programmed to derive one or more characteristics from the sensor signals, wherein the one or more characteristics are locally affected by myocardial ischemia or infarction;

wherein the controller is programmed to measure the one or more characteristics over time and establish baseline values for the measured characteristics; and

,

wherein the controller is programmed to detect myocardial ischemia/infarction when a deviation from the baseline in one or more characteristics occurs above a specified threshold.

2. The device of claim 1 wherein the sensors are electrodes for detecting cardiac electrical activity.

3. The device of claim 2 wherein the derived characteristic is an intrinsic activation time.

4. The device of claim 2 wherein the derived characteristic is an electrogram amplitude.

5. The device of claim 2 wherein the derived characteristic is a time interval between the start of depolarization and the end of repolarization in an electrogram signal.

6. The device of claim 2 wherein the derived characteristic is the duration of depolarization in an electrogram signal.

7. The device of claim 2 wherein the derived characteristic is a morphological feature of the electrogram as detected by correlation with a patient-specific template waveform.

8. The device of claim 2 further comprising one or more pacing channels into which may be incorporated the plurality of electrodes and wherein the derived characteristic is a pacing capture threshold.

9. The device of claim 1 wherein the sensors are sensors for detecting myocardial displacement or strain.

10. The device of claim 1 wherein the controller is further programmed to localize an ischemic/infarcted region(s) by analyzing the magnitudes of the measured characteristics as derived from differently located sensors.

11. The device of claim 1 wherein the controller is further programmed to issue an alert by transmission of an alert message to a remote monitor via telemetry upon detection of ischemia/infarction.

12. The device of claim 10 further comprising:

a plurality of electrodes configurable into pacing channels that are adapted for disposition at a plurality of myocardial sites; and

,

wherein the controller is programmed to configure selected ones of the plurality of electrodes into pacing channels for delivering pre-excitation pacing to selected myocardial sites in or around the localized ischemic/infarcted region.

13. A method, comprising:

receiving signals from a plurality of sensors disposed near different myocardial regions;

deriving one or more characteristics from the sensor signals, wherein the one or more characteristics are locally affected by myocardial ischemia or infarction;

measuring the one or more characteristics over time and establish baseline values for the measured characteristics; and

,

detecting myocardial ischemia/infarction when a deviation from the baseline in one or more characteristics occurs above a specified threshold.

14. The method of claim 13 wherein the sensors are electrodes for detecting cardiac electrical activity.

15. The method of claim 14 wherein the derived characteristic is an intrinsic activation time.

16. The method of claim 14 wherein the derived characteristic is an electrogram amplitude.

17. The method of claim 14 wherein the derived characteristic is a time interval between the start of depolarization and the end of repolarization in an electrogram signal.

18. The method of claim 14 wherein the derived characteristic is the duration of depolarization in an electrogram signal.

19. The method of claim 14 wherein the derived characteristic is a morphological feature of the electrogram as detected by correlation with a patient-specific template waveform.

20. The method of claim 13 further comprising localizing an ischemic/infarcted region(s) by analyzing the magnitudes of the measured characteristics as derived from differently located sensors.