High-Sensitivity Cardiac Troponin T to OPtimize Chest Pain Risk Stratification

Study Overview
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Brief Summary
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This is a prospective observational cohort study of ED patients with acute chest pain or other symptoms suggestive of ACS. Blood samples will be collected from study participants for High-Sensitivity Cardiac Troponin T (hs-cTnT) analysis. Results from hs-cTnT will be used for research purposes only. Providers will be blinded to results and participants will be treated by their healthcare providers per the standard of care. Participants will have 30 and 90 day phone follow-ups to ascertain study outcomes.

Detailed Description
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Approximately 8 million - 10 million patients complaining of chest pain present to an Emergency Department (ED) annually in the United States. To avoid missing the diagnosis of acute coronary syndrome (ACS), physicians use a liberal testing strategy. Thus, >50% of ED patients with acute chest pain are hospitalized for a comprehensive cardiac evaluation (serial cardiac biomarkers and stress testing or angiography). However, <10% of these patients are ultimately diagnosed with ACS, and this pervasive over-triage costs an estimated $10 billion - $13 billion annually. Current care patterns for acute chest pain fail to focus health system resources, such as hospitalization and stress testing, on patients most likely to benefit. It has demonstrated that an accelerated diagnostic protocol (ADP), called the HEART Pathway, which utilizes a clinical decision aid (the HEART score) and serial Cardiac Troponin (cTn) measures are sensitive for ACS (>99%) and can substantially reduce hospitalizations, stress testing, and cost compared to usual care. The HEART Pathway uses contemporary serial cTn measurements at 0 and 3 hours to exclude index myocardial infarction (MI) and relies on clinical features (history, ECG, age, and risk factors) to identify patients likely to have downstream events. However, the HEART Pathway has limitations: a) It identifies only 20 - 40% of patients for early discharge and b) it was developed before high-sensitivity cTn assays became available. Able to detect MI earlier and with greater accuracy than contemporary assays, hs-cTn assays have the potential to be integrated into decision aids to improve chest pain risk stratification. In the near future, hs-cTn assays will replace contemporary assays in the United States.

Official Title
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High-Sensitivity Cardiac Troponin T to OPtimize Chest Pain Risk Stratification

Conditions
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Acute Coronary Syndrome, Chest Pain

Intervention / Treatment
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* Procedure: Blood Sample
* Behavioral: HEART Score


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age greater than or equal to 21 years at the time of enrollment in the ED Chest discomfort or other symptoms consistent with possible ACS in which the treating physician plans to obtain an ECG and cTn for the patient's evaluation in the ED Exclusion Criteria: New ST-segment elevation consistent with myocardial infarction Evidence of shock identified by the provider at the bedside and/or the PI Terminal diagnosis with life expectancy less than 90 days A non-cardiac medical, surgical, or psychiatric illness determined by the provider to require admission Prior enrollment in the STOP CP study Lack of capacity to provide consent and comply with study procedures Inability to be reliably reached after the index visit for follow-up Non-English speaking Pregnant patients Provider does not intend on obtaining serial cTn assays for evaluation of ACS The first study draw (T0) will exceed 1 hour after the site-specific standard of care troponin draw Unable or unwilling to authorize medical records release

Ages Eligible for Study
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Minimum Age: 21 Years

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 |
| --- | --- |
| ED Patients with Acute Chest Pain<br>Emergency Department (ED) Patients with Acute Chest Pain will have blood samples collected for High sensitivity cardiac troponin T (hs-CTnT) analysis. Results from this analysis will be integrated into the HEART Score/Pathway. It will later be seen if integration of the hs-cTnT outperforms the use of HEART Score/Pathway alone. | Procedure: Blood Sample<br>* Blood samples will be collected from study participants for hs-cTnT analysis. Results of hs-cTnT will be used for research purposes only. Providers and participants will be blinded to results and participants will be treated by their healthcare providers per the standard of care.<br>* Other names: Blood draw;Behavioral: HEART Score<br>* The HEART Score is a prospectively studied scoring system to help emergency departments risk-stratify chest pain patients. Patients score on a scale of 0-10.<br>* Other names: HEART Pathway;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| High Sensitivity Cardiac Troponin T using lithium heparin tubes | The research team will obtain two lithium heparin tubes at baseline, 1, 2, and 3 hours for sampling and preparation for shipping to the core laboratory in Maryland for hs-cTnT processing. Providers will be blinded to hs-cTnT results. | Baseline | 
| High Sensitivity Cardiac Troponin T using lithium heparin tubes | The research team will obtain two lithium heparin tubes at baseline, 1, 2, and 3 hours for sampling and preparation for shipping to the core laboratory in Maryland for hs-cTnT processing. Providers will be blinded to hs-cTnT results. | 1 hour after baseline | 
| High Sensitivity Cardiac Troponin T using lithium heparin tubes | The research team will obtain two lithium heparin tubes at baseline, 1, 2, and 3 hours for sampling and preparation for shipping to the core laboratory in Maryland for hs-cTnT processing. Providers will be blinded to hs-cTnT results. | 2 hours after baseline | 
| High Sensitivity Cardiac Troponin T using lithium heparin tubes | The research team will obtain two lithium heparin tubes at baseline, 1, 2, and 3 hours for sampling and preparation for shipping to the core laboratory in Maryland for hs-cTnT processing. Providers will be blinded to hs-cTnT results. | 3 hours after baseline | 
| High Sensitivity Cardiac Troponin T using EDTA tubes | The research team will obtain one EDTA tube at baseline, 1, 2, and 3 hours for sampling and preparation for shipping to the core laboratory in Maryland for hs-cTnT processing. Providers will be blinded to hs-cTnT results. | Baseline | 
| High Sensitivity Cardiac Troponin T using EDTA tubes | The research team will obtain one EDTA tube at baseline, 1, 2, and 3 hours for sampling and preparation for shipping to the core laboratory in Maryland for hs-cTnT processing. Providers will be blinded to hs-cTnT results. | 1 hour after baseline | 
| High Sensitivity Cardiac Troponin T using EDTA tubes | The research team will obtain one EDTA tube at baseline, 1, 2, and 3 hours for sampling and preparation for shipping to the core laboratory in Maryland for hs-cTnT processing. Providers will be blinded to hs-cTnT results. | 2 hours after baseline | 
| High Sensitivity Cardiac Troponin T using EDTA tubes | The research team will obtain one EDTA tube at baseline, 1, 2, and 3 hours for sampling and preparation for shipping to the core laboratory in Maryland for hs-cTnT processing. Providers will be blinded to hs-cTnT results. | 3 hours after baseline | 
| Cardiac Troponin T (cTn) | Site-specific cTn will be measured at baseline | Baseline | 
| Cardiac Troponin T (cTn) | Site-specific cTn will be measured at 3 hours unless baseline site-specific cTn tests positive | 3 hours | 
| Occurrence of major adverse cardiac events (MACE) |  | 30 days | 
| Occurrence of major adverse cardiac events (MACE) |  | 90 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| HEART Score Calculation | By assigning zero, one, or two points - towards an atypical patient history, ECG anomalies, the patient's age, any risk factors present, and elevated Troponin - patients score on a scale of 0-10. 0-3 = Low-risk, 4 or greater = High-risk | Change from Baseline, 1, 2, 3 hours. 30 days and 90 days post discharge | 
| Incidence and Intensity of Adverse Events | Number of Participants with treatment related Adverse Events as Assessed by CTCAE v4.0 | Change from Baseline, 1, 2, 3 hours. 30 days and 90 days post discharge |