Apparatus and method for risk stratification of patients with chest pain of suspected cardiac origin

• US 20050004485A1
• Filed: 05/19/2003
• Published: 01/06/2005
• Est. Priority Date: 05/19/2003
• Status: Active Grant

• Current Assignee: Ischemia Technologies, Inc. (Abbott Laboratories Incorporated)
• Original Assignee: Ischemia Technologies, Inc. (Abbott Laboratories Incorporated)
• Inventors: Morris, Deborah L., Soane, Mark M., Crosby, Peter A.
• Granted Patent: US 7,074,194 B2
• Time in Patent Office: Days
• US Class Current: 600/513
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• 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: G01N 2800/324 Coronary artery diseases, e.g. angina pectoris, myocardial infarction
• CPC Class Codes: G01N 2800/50 Determining the risk of developing a disease
• CPC Class Codes: G01N 2800/56 Staging of a disease; Further complications associated with the disease
• CPC Class Codes: G01N 33/5302 Apparatus specially adapted for immunological test procedures
• CPC Class Codes: G01N 33/6893 related to diseases not provided for elsewhere
• CPC Class Codes: G16H 10/40 for data related to laboratory analysis, e.g. patient specimen analysis
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment

Abstract

The subject invention relates to the detection, diagnosis and risk stratification of clinical events such as acute coronary syndrome, in patients with signs and symptoms of suspected cardiac origin. In one embodiment, a clinical event in a patient is diagnosed by obtaining the patient'"'"'s ECG, and at least one in vitro diagnostic assay, preferably an assay for a marker of ischemia, and optionally in vitro diagnostic assays for necrotic markers or other cardiac indicators, and combining the foregoing results in an algorithm to provide a diagnosis or a risk stratification of the clinical condition.

Claims

1. A method for diagnosis of a clinical condition in a patient or for risk stratification of a patient possibly with the condition, comprising the steps of:

a) obtaining from the patient at least one sample of a substance stream which has been in contact with a tissue suspected of undergoing the clinical condition;

b) conducting at least a first in vitro diagnostic assay on the sample and optionally additional in vitro diagnostic assays;

c) measuring and analyzing the patient'"'"'s electrocardiogram (ECG); and

d) applying an algorithm to combine the results of the assay(s) of step (b) and the electrocardiogram in step (c) using an algorithm to provide a positive or negative diagnosis or risk stratification of the clinical condition.

2. The method of claim 1 where the first in vitro diagnostic assay is an assay for a marker of ischemia.

3. The method of claim 1 where the substance stream is selected from the group consisting of whole blood, serum, plasma, saliva, urine, feces, semen, mucus, tears, breath, or sweat.

4. The method of claim 1 further comprising, the steps of:

e) storing the results of the assay(s) from the stream sample and ECG results for the patient in a memory means;

f) storing a clinical outcome of the patient into the memory means;

g) comparing assay and ECG results in the memory with the clinical outcome;

h) modifying the algorithm in response to the comparison to provide improved diagnosis or risk stratification; and

i) repeating steps (a)-(h) with a plurality of patients whereby an improved algorithm is provided.

5. The method of claim 1, wherein the clinical event is an acute myocardial infarction.

6. The method of claim 1 wherein the clinical event is stable angina.

7. The method of claim 1 wherein the clinical event is unstable angina.

8. The method of claim 1 wherein the clinical event is acute coronary syndrome.

9. The method of claim 1, wherein the additional in vitro diagnostic assay is an assay for a necrosis marker selected from the group consisting of troponin, CK-MB and myoglobin.

10. The method of claim 1, wherein the additional in vitro diagnostic assay is an assay for B-type natriuretic peptide (BNP) or associated molecules.

11. The method of claim 1, wherein the additional in vitro diagnostic assay is an assay for C Reactive Protein (CRP).

12. The method of claim 3, wherein the marker for ischemia is ischemia modified albumin.

13. The method of claim 1, wherein the additional in vitro diagnostic assay is an assay for adenosine in expired breath.

14. The method of claim 1, wherein first assay is selected from the group consisting of an albumin cobalt binding (ACB®

) test, an electrochemical test for ischemia modified albumin, an optical test for ischemia modified albumin, an immunoassay for ischemia modified albumin, and a metal affinity assay for ischemia modified albumin.

15. The method of claim 2, wherein the algorithm provides a negative diagnosis or indication of lower risk if the ECG is either non-diagnostic or normal, and the ischemic marker assay result is negative.

16. The method of claim 1, wherein the algorithm provides a negative diagnosis or indication of lower risk if the ECG is either non-diagnostic or normal, and a majority of the first and additional in vitro assay results are negative.

17. The method of claim 1, wherein the algorithm provides a positive diagnosis or elevated risk stratification if the ECG is normal or non-diagnostic and at least one of the first and additional in vitro diagnostic assays is positive.

18. The method of claim 9, wherein the algorithm provides for a positive diagnosis or indication of higher risk if the ECG is non-diagnostic or normal, the additional in vitro assay for the marker of necrosis is negative and the first in vitro assay is for a marker of ischemia and is positive.

19. The method of claim 1, wherein the algorithm provides a positive diagnosis or indication of higher risk if the ECG is positive and at least one of the first or additional in vitro diagnostic assays is positive.

20. The method of claim 1, further comprising repetition of steps (a) and (b) and/or repetition of step (c), followed by repetition of step (d), whereby information about the patient'"'"'s status within a time course of the clinical condition can be obtained.

21. The method of claim 20, wherein the information is severity of the clinical condition.

22. The method of claim 20, wherein the clinical condition is ACS, and wherein the information is an estimated time of onset or severity of acute myocardial infarction or unstable angina.

23. A method for diagnosis of a acute coronary syndrome (ACS) or for risk stratification of a patient with suspected ACS, comprising the steps of:

a) obtaining at least one blood fraction sample from the patient;

b) conducting at least one in vitro diagnostic assay for a marker of ischemia and at least one in vitro diagnostic assay for a marker of necrosis on the sample;

c) measuring and analyzing the patient'"'"'s electrocardiogram (ECG); and

d) combining the results of the assay(s) of step (b) and the ECG in step (c) using an algorithm to provide a positive or negative diagnosis of ACS or indication of the risk that the patient has ACS.

24. The method of claim 23, wherein the diagnosis of ACS includes at least one diagnosis selected from the group consisting of acute myocardial infarction, unstable angina, stable angina and cardiac ischemia.

25. The method of claim 23, wherein the marker for necrosis is selected from the group consisting of troponin, CK-MB and myoglobin.

26. The method of claim 23, wherein the diagnostic assay for a marker of ischemia is selected from the group consisting of albumin cobalt binding (ACB®

) test, an electrochemical test for ischemia modified albumin, an optical test for ischemia modified albumin, an immunoassay for ischemia modified albumin, and metal affinity assay for ischemia modified albumin.

27. The method of claim 23, wherein the algorithm provides a negative diagnosis or indication of lower risk of ACS if the ECG is either non-diagnostic or normal, and results of the assay for a marker of necrosis and the assay for the marker of ischemia are negative.

28. The method of claim 23, wherein the algorithm provides a positive diagnosis or indication of higher risk if the ECG is normal or non-diagnostic and at least one of the in vitro diagnostic assays for a marker of ischemia and the in vitro diagnostic assays for a marker of necrosis is positive.

29. The method of claim 23, wherein the algorithm provides for a positive diagnosis or indication of higher risk if the ECG is non-diagnostic or normal, the in vitro assay for a marker of necrosis is negative and the in vitro assay for a marker of ischemia is positive.

30. The method of claim 23, wherein the algorithm provides a positive diagnosis or indication of higher risk if the ECG is positive and at least one of the in vitro assays is positive.

31. The method of claim 23, further comprising repetition of steps (a) and (b) and/or repetition of step (c), followed by repetition of step (d), whereby information about a patient'"'"'s status within a time course of the ACS can be obtained.

32. The method of claim 31, wherein the information is the onset of the occurrence of the ACS.

33. The method of claim 31, wherein the information is the severity of the ACS.

34. An apparatus for diagnosis of a clinical condition or estimating the probability of the presence of the condition in a patient, comprising:

an electronic module housing comprising a display means;

a data entry and control means;

a means for measuring an electrocardiogram (ECG);

an aperture containing a reader means;

an analysis means in electrical continuity with the data entry and control means, the ECG means, and the reader means, whereby said analysis means can analyze signals from each said means;

a power source; and

optionally a link to a laboratory or hospital information system;

wherein said aperture is adapted to receive a sample analysis strip for conducting an in vitro diagnostic assay on a patient sample of a substance stream, and said reader is adapted to read results of said assay;

whereby said analyzer receives signals from said ECG means and said data entry and control means, and upon insertion of said strip into said aperture, from said reader means, and said analyzer means transmits analyzed results to said display means.

35. The apparatus of claim 34, wherein the reader means comprises at least one reader device capable of reading results of an assay for a marker of ischemia, and/or assay results of an assay for a marker of necrosis on the sample analysis strip.

36. The apparatus of claim 34, wherein said link to a laboratory or hospital information system is selected from the group consisting of a direct electrical connection, an infrared link and a wireless link.