Method and system for detecting acute myocardial infarction

• US 5,792,066 A
• Filed: 01/09/1997
• Issued: 08/11/1998
• Est. Priority Date: 01/09/1997
• Status: Expired due to Term

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Kwong, Manlik
• Primary Examiner(s): Kamm, William E.
• Assistant Examiner(s): EVANISKO, GEORGE ROBERT
• Application Number:
  US08/780,648
• Time in Patent Office: 579 Days
• Field of Search: 128/696, 128/702, 128/704, 600/509, 600/515, 600/517
• US Class Current: 600/517
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/7264 Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems neural networks per se G06N3/00; expert systems per se G06N5/00

Abstract

A method and system for determining Acute Myocardial Infarction. The method and system work by determining whether or not at least one pre-specified component wave is present within each successive heartbeat waveform (e.g. the S wave component of the QRSTU waveform) appearing within each electrocardiographic lead. After it has been determined whether or not the pre-specified component wave is present within the heartbeat waveforms under consideration (each lead will generally have some representation of each successive heartbeat waveform present within it), a wave amplitude ratio (e.g. the ST complex amplitude divided by the S wave component amplitude at some specified instant in time) is calculated. Thus, for each successive heartbeat waveform there will generally be at least one wave amplitude ratio calculated for each electrocardiographic lead, since the same heartbeat waveform generally appears, in some form, within each electrocardiographic lead. Finally, the calculated wave amplitude ratios, which are generally calculated on each lead that every successive heartbeat waveform, are compared to predetermined criteria (e.g. traversing a classification tree), and on the basis of this comparison it is indicated whether Acute Myocardial Infarction is occurring.

Claims

1. A method for detecting an occurrence of Acute Myocardial Infarction on the basis of a patient'"'"'s electrocardiographic waveform data, said electrocardiographic waveform data including at least one heartbeat waveform and wherein said at least one heartbeat waveform comprises at least one of P, Q, R, S, and T component waves and wherein said at least one heartbeat waveform can be partitioned to form an ST segment, even when said patient has an underlying heart condition which mimics standard criteria for detecting Acute Myocardial Infarction, said method comprising the steps of:

obtaining one or more electrocardiographic leads having said patient'"'"'s electrocardiographic waveform data;

determining whether or not at least one predetermined component wave is present within each successive heartbeat waveform appearing within each electrocardiographic lead;

in response to said determining step, calculating at least one wave amplitude ratio, wherein said wave amplitude ratio is a ratio of an ST segment to said at least one predetermined component wave, for each electrocardiographic lead in which said each successive heartbeat waveform appears; and

in response to said calculated at least one wave amplitude ratio for each electrocardiographic lead in which said each successive heartbeat waveform appears meeting predetermined criteria, indicating an occurrence of Acute Myocardial Infarction.

2. The method of claim 1, wherein said calculating step of determining whether or not at least one predetermined component wave is present within each successive heartbeat waveform appearing within each electrocardiographic lead comprises the step of determining whether or not an S wave is present within each successive heartbeat waveform appearing within each electrocardiographic lead.

3. The method of claim 2, wherein said calculating step further comprises the steps of:

for said each electrocardiographic lead in which said each successive heartbeat waveform appears and in which it is determined that no S wave is present, assigning an ST/S wave amplitude ratio to be zero; and

for said each electrocardiographic lead in which said each successive heartbeat waveform appears and in which it is determined that an S wave is present;

obtaining an ST segment amplitude;

obtaining an S wave amplitude; and

calculating said ST/S wave amplitude ratio by dividing an ST amplitude by an amplitude of said S wave.

4. The method of claim 1, wherein said step of indicating an occurrence of Acute Myocardial Infarction comprises the steps of:

traversing a classification tree utilizing said calculated at least one wave amplitude ratio for each electrocardiographic lead in which said each successive heartbeat waveform appears;

in response to said traversing step, classifying said calculated at least one wave amplitude ratio for each electrocardiographic lead in which said each successive heartbeat waveform appears as either indicative of or not indicative of Acute Myocardial Infarction; and

in response to said classifying step, indicating the occurrence of Acute Myocardial Infarction if said calculated at least one wave amplitude ratio for each electrocardiographic lead in which said each successive heartbeat waveform appears was classified as indicative of Acute Myocardial Infarction.

5. A system for detecting an occurrence of Acute Myocardial Infarction on the basis of a patient'"'"'s electrocardiographic waveform data, sad electrocardiographic waveform data including at least one heartbeat waveform and wherein said at least one heartbeat waveform comprises at least one of P, Q, R, S, and T component waves and wherein said at least one heartbeat waveform can be partitioned to form an ST segment, even when said patient has an underlying heart condition which mimics standard criteria for detecting Acute Myocardial Infarction, said system comprising:

means for obtaining one or more electrocardiographic leads having said patient'"'"'s electrocardiographic waveform data;

means for determining whether or not at least one predetermined component wave is present within each successive heartbeat waveform appearing within each electrocardiographic lead;

means, responsive to said determining step, for calculating at least one wave amplitude ratio, wherein said wave amplitude ratio is a ratio of an ST segment and said at least one predetermined component wave, for each electrocardiographic lead in which said each successive heartbeat waveform appears; and

means, responsive to said calculated at least one wave amplitude ratio for each electrocardiographic lead in which said each successive heartbeat waveform appears meeting predetermined criteria, for indicating an occurrence of Acute Myocardial Infarction.

6. The system of claim 5, wherein said means for determining whether or not at least one predetermined component wave is present within each successive heartbeat waveform appearing within each electrocardiographic lead comprises means for determining whether or not an S wave is present within each successive heartbeat waveform appearing within each electrocardiographic lead.

7. The system of claim 6, wherein means for calculating further comprises:

for said each electrocardiographic lead in which said each successive heartbeat waveform appears and in which it is determined that no S wave is present, means for assigning an ST/S wave amplitude ratio to be zero; and

for said each electrocardiographic lead in which said each successive heartbeat waveform appears and in which it is determined that an S wave is present;

means for obtaining an ST segment amplitude;

means for obtaining an S wave amplitude; and

means for calculating said ST/S wave amplitude ratio by dividing an ST amplitude by an amplitude of said S wave.

8. The system of claim 5, wherein said means for indicating an occurrence of Acute Myocardial Infarction comprises:

means for traversing a classification tree utilizing said calculated at least one wave amplitude ratio for each electrocardiographic lead in which said each successive heartbeat waveform appears;

means, responsive to said traversing step, for classifying said calculated at least one wave amplitude ratio for each electrocardiographic lead in which said each successive heartbeat waveform appears as either indicative of or not indicative of Acute Myocardial Infarction; and

means, responsive to said classifying step, for indicating the occurrence of Acute Myocardial Infarction if said calculated at least one wave amplitude ratio for each electrocardiographic lead in which said each successive heartbeat waveform appears was classified as indicative of Acute Myocardial Infarction.