EKG Criteria and Identification of Acute Coronary Occlusion

Study Overview
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Brief Summary
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The objective of this research study is to test the accuracy of preexisting criteria versus expert interpretation for the diagnosis of acute coronary occlusion (major heart attack due to a completely blocked blood vessel). If our hypothesis proves to be true, this would provide a significant improvement in the care for patients who present to the hospital with possible symptoms of coronary ischemia (symptoms due to lack of blood flow to the heart). The primary analysis will be designed as a multi-center, retrospective case-control study.

Detailed Description
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In this retrospective, 2-center, case-control study the investigators will investigate and compare the accuracy of various ECG criteria and expert interpretation to diagnose Acute Coronary Occlusion (ACO), with an emphasis on the diagnosis of patients with ACO but without obvious ST segment Elevation Myocardial Infarction (STEMI) criteria. The investigators will use two cohorts of patients who present with symptoms consistent with acute MI, one subsequently proven to have ACO and one proven to not have ACO. The groups will be identified by chart reviewers who will use all clinical data except the ECGs to determine, in retrospect, and using strict criteria, if the patient had ACO at the time of the ECGs to be evaluated, or not. These reviewers will be blinded to all ECGs. The diagnosis of ACO will be dependent upon angiographic occlusion. Because in many cases of ACO, the artery spontaneously opens by the time of the angiogram, the investigators will need to have surrogate endpoints: this will be culprit on the angiogram PLUS a very elevated peak troponin, as peak troponin I > 10.0 ng/mL and peak troponin T > 1.0 ng/mL are highly correlated with ACO. The investigators will find cases of subtle STEMI (ACO without STEMI criteria) by searching for all myocardial infarction cases that underwent angiography and percutaneous coronary intervention (PCI). The investigators will attempt by various criteria to determine from all available sources other than the ECG (angiography, echo, troponins) whether the involved artery was occluded at the time of the most diagnostic ECG that was recorded while the patient had symptoms and before the angiogram. Reviewers determining ACO or not ACO will be blinded to the ECGs. The investigators will use each pre-angiogram ECG, in sequence, for analysis, to determine if expert interpretation can not only identify occlusion that is not identified by STEMI criteria, but also to find if expert interpretation can identify occlusion on an earlier ECG. Expert ECG interpreters will interpret the ECG for evidence of ACO. Their accuracy will be compared to traditional STEMI criteria and other methods of interpretation if available. The investigators will use as controls patients with any ST elevation, or ST depression, of any etiology that are proven to NOT have occlusion. The investigators will establish absence of occlusion by a combination of objective data points including angiogram (if performed), troponins, echocardiograms, clinical course, etc. Details of the methods are below, including specific outcome definitions used to claim the presence or absence of ACO.

Official Title
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EKG Criteria and Identification of Acute Coronary Occlusion

Conditions
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Acute Coronary Syndrome, STEMI, STEMI - ST Elevation Myocardial Infarction, Acute Coronary Artery Thrombosis (Diagnosis), NSTEMI - Non-ST Segment Elevation MI, Non-ST Elevation Myocardial Infarction, Non ST Segment Elevation Myocardial Infarction, Non ST Segment Elevation Acute Coronary Syndrome, Non-ST Elevation Myocardial Infarction (nSTEMI), Non STEMI

Intervention / Treatment
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* Other: No intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Recorded EKG prior to cardiac catheterization Exclusion Criteria: Absence of documented EKG prior to cardiac catheterization
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Acute Coronary Occlusion or near-occlusion (TIMI 0-1)<br>a. Acute occlusion proven on angiogram (an acute culprit lesion with TIMI 0-1 flow, or description of acute total thrombotic occlusion) b. Acute culprit lesion (any TIMI score) with Peak cTNI > 10 ng/mL or cTnT > 1.0 ng/mL c. If no catheterization performed (contraindicated, not compatible with goals of care, etc), then highly elevated troponin as above plus a new/presumed new focal wall motion abnormality on echocardiography d. Positive ECG findings (by any criteria) with death occurring before attempted emergent coronary angiography and autopsy confirming ACO. For cases with positive ECG findings and death before cath but NO autopsy, these will be marked and saved in a separate group, not to be used in the primary analysis. | Other: No intervention<br>* There will be no intervention as a part of this protocol.<br>|
| Acute Coronary Occlusion or near-occlusion (TIMI 0-2)<br>a. Acute occlusion proven on angiogram (an acute culprit lesion with TIMI 0-2 flow, or description of acute total thrombotic occlusion) b. Acute culprit lesion (any TIMI score) with Peak cTNI > 10 ng/mL or cTnT > 1.0 ng/mL c. If no catheterization performed (contraindicated, not compatible with goals of care, etc), then highly elevated troponin as above plus a new/presumed new focal wall motion abnormality on echocardiography d. Positive ECG findings (by any criteria) with death occurring before attempted emergent coronary angiography and autopsy confirming ACO. For cases with positive ECG findings and death before cath but NO autopsy, these will be marked and saved in a separate group, not to be used in the primary analysis. | Other: No intervention<br>* There will be no intervention as a part of this protocol.<br>|
| Acute severe 3-vessel disease or critical left main stenosis<br>Severe 3-vessel disease: >/=75% stenosis in all three major coronary vessels (or equivalents in the case of anatomic variants or preexisting bypass) with an acute culprit lesion (TIMI<3) or Left main stenosis > 50% (see Smith review paper for reference): acute left main culprit of any TIMI score, or any lesion of the left main with TIMI<3 or Any other cardiac catheterization findings prompting initiation of emergent coronary artery bypass grafting within the next 120 hours | Other: No intervention<br>* There will be no intervention as a part of this protocol.<br>|
| No evidence of acute coronary occlusion<br>At least three sequential negative cardiac biomarkers within 24 hours of presentation cardiac catheterization showing no culprit lesion. Angiogram showing an acute culprit lesion but both no occlusion (TIMI 2 or greater) and troponins not exceeding the cutoff above If positive troponin values present but no angiography, then the patient must have echocardiography showing no wall motion abnormality and troponin values less than the above cutoff If the patient has insufficient data to classify into one of these categories, the patient must be excluded from the study as they cannot be classified as ACO or non-ACO. For example, patients with extremely high troponin but no culprit seen on cath may have acute occlusion with complete autolysis of thrombus, myocarditis, spasm, etc. Thus the investigators cannot classify them as NO ACO when the possibility of ACO remains and cannot be disproven. | Other: No intervention<br>* There will be no intervention as a part of this protocol.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The difference in time to diagnosis of acute coronary occlusion (ACO) between the current standard of care and advanced human ECG interpretation in patients with confirmed occlusive myocardial infarction without ST elevation myocardial infarction | How long does it take for an expert human ECG interpreter to diagnose ACO compared to the standard of care utilizing STEMI criteria | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The difference in sensitivity among the occlusive myocardial infarction (OMI) cohort for experts versus ST elevation myocardial infarction (STEMI) criteria | The difference in sensitivity among the occlusive myocardial infarction cohort for experts versus STEMI criteria | 1 year | 
| The difference in sensitivity among the occlusive myocardial infarction (OMI) cohort for experts versus ST elevation myocardial infarction (STEMI) criteria in all studied patients | The difference in sensitivity among the occlusive myocardial infarction (OMI) cohort for experts versus ST elevation myocardial infarction (STEMI) criteria in all studied patients | 1 year | 
| The difference in sensitivity among the occlusive myocardial infarction (OMI) cohort for experts versus ST elevation myocardial infarction (STEMI) criteria in patients with widened QRS | The difference in sensitivity among the occlusive myocardial infarction (OMI) cohort for experts versus ST elevation myocardial infarction (STEMI) criteria in patients with widened QRS | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Acute Coronary Occlusion, ACO, Occlusive Myocardial Infarction, OMI, Non-occlusive Myocardial Infarction, NOMI