System and method for automated diagnosis of myocardial ischemia through remote monitoring

• US 8,672,856 B2
• Filed: 10/31/2007
• Issued: 03/18/2014
• Est. Priority Date: 11/16/1999
• Status: Expired due to Fees

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Bardy, Gust H.
• Primary Examiner(s): EVANISKO, GEORGE ROBERT
• Application Number:
  US11/932,550
• Publication Number:
  US 20080058661A1
• Time in Patent Office: 2,330 Days
• Field of Search: 607/4, 607/5, 607/9, 600/508, 600/509
• US Class Current: 600/508
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/02 Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/02438 with portable devices, e.g. worn by the patient
• CPC Class Codes: A61B 5/029 Measuring or recording blood output from the heart, e.g. minute volume A61B8/065 takes precedence
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/361 Detecting fibrillation
• CPC Class Codes: A61B 5/366 Detecting abnormal QRS complex, e.g. widening
• CPC Class Codes: A61B 5/486 Bio-feedback A61B5/375 takes precedence
• CPC Class Codes: A61N 1/36507 controlled by gradient or slope of the heart potential
• CPC Class Codes: G16H 10/60 for patient-specific data, e.g. for electronic patient records
• CPC Class Codes: G16H 15/00 ICT specially adapted for medical reports, e.g. generation or transmission thereof
• CPC Class Codes: G16H 20/40 relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture
• CPC Class Codes: G16H 40/67 for remote operation
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

A system and method for automated diagnosis of myocardial ischemia through remote monitoring is described. Physiological measures comprising data either recorded on a regular basis by a medical device or derived therefrom is stored. Qualitative measures associated with the physiological measures are matched. Indications of myocardial ischemia are remotely identified. The qualitative measures for both of a reduction in exercise capacity and respiratory distress occurring contemporaneously are examined. The qualitative measures for angina that accompanies the reduction in exercise capacity and the respiratory distress are evaluated. A time course for each of the indications is determined. A patient status is formed comprising an onset of myocardial ischemia conditioned on the time course comprising a short duration.

Claims

1. A system for automated monitoring, comprising:

a database module configured to store physiological measures comprising collected and derived measures from an implantable medical device, reference baseline data, and patient cardiovascular measures having at least an ST segment and a QRS segment; and

a diagnostic module configured to

determine a patient status change over a time period for a patient by comparing at least one stored physiological measure of the patient at a first time to at least one other stored physiological measure of the patient at a second time, wherein the at least one stored physiological measure is the same physiological measure as the at least one other stored physiological measure;

compare the patient status change over the time period to one or more predetermined rate-of-change indicator thresholds, the one or more rate-of-change indicator thresholds comprising a quantifiable physiological measure of pathophysiology indicative of myocardial ischemia;

compare the at least one stored physiological measure of the patient at the first time to an absolute threshold limit indicative of myocardial ischemia, wherein the diagnostic module is configured to utilize the one or more indicator thresholds to confirm an absence of a QRS duration greater than or equal to 120 ms when the ST segment elevation exceeds 2.0 mm and declare the elevation of the ST segment as an a priori indicator of the myocardial ischemia upon said confirmation, and

utilize the one or more indicator thresholds to evaluate ST segment elevation and depression and further specify ST segment elevation as an indicator myocardial ischemia.

2. The system of claim 1, wherein the one or more rate-of-change indicator thresholds comprises the rate of change of one or more quality of life measures.

3. The system of claim 1, wherein the one or more rate-of-change indicator thresholds comprises a reduction in exercise tolerance.

4. A method for automated monitoring, comprising:

storing physiological measures comprising collected and derived measures from an implantable medical device and reference baseline data, wherein the physiological measures comprise ECG measures;

determining indications of cardiac ischemia, comprising;

determining a patient status change over a time period for a patient by comparing at least one stored physiological measure of the patient at a first time to at least one other stored physiological measure of the patient at a second time, wherein the at least one stored physiological measure is the same physiological measure as the at least one other stored physiological measure;

comparing the patient status change over the time period to one or more rate-ofchange indicator thresholds, the one or more rate-of-change indicator thresholds comprising a quantifiable physiological measure of pathophysiology indicative of myocardial ischemia;

evaluating ST segment elevation and depression utilizing the one or more indicator thresholds;

specifying ST segment elevation as an indicator myocardial ischemia; and

comparing the at least one stored physiological measure of the patient at the first time to an absolute threshold limit indicative of myocardial ischemia comprising;

confirming an absence of a QRS duration greater than or equal to 120ms utilizing the one or more indicator thresholds when the ST segment elevation exceeds 2.0 mm; and

declaring the elevation of the ST segment as an a priori indicator of the myocardial ischemia upon said confirmation.

5. The method of claim 4, wherein the one or more rate-of-change indicator thresholds comprises the rate of change of one or more quality of life measures.

6. The method of claim 4, wherein the one or more rate-of-change indicator thresholds comprises a reduction in exercise tolerance.