Efficacy Evaluation of the HEART Pathway in Emergency Department Patients With Acute Chest Pain (HEART Pathway)

Our research will examine a chest pain care strategy, called the HEART pathway, which is designed to correctly identify Emergency Department patients at high-risk for cardiovascular events, likely to benefit from further testing, and patients at very-low-risk for cardiovascular events, who may be safely discharged home. By using an individual's risk assessment to determining testing, we hope to improve the quality and efficiency of the care delivered to Emergency Department patients with chest pain. Our study will determine if the HEART pathway, which combines a clinical decision rule, the HEART score, and two serial troponin measurements, will reduce stress testing and cardiovascular imaging, decrease hospital length of stay, and reduce cost compared to usual care, while maintaining safety.

Approximately 8-10 million patients complaining of chest pain present to an Emergency Department (ED) annually in the United States. The total cost of chest pain evaluations has been estimated at $5-10 billion annually, yet only 10% of these patients are ultimately diagnosed with an acute coronary syndrome. American College of Cardiology/ American Heart Association (ACC/AHA) guidelines recommend that patients at low-risk for acute coronary syndrome should receive serial cardiac markers followed by objective cardiac testing (stress testing or cardiac imaging). However, many have questioned the value of objective cardiac testing in all low-risk patients.Cardiac testing for all patients at low-risk for acute coronary syndrome (ACS) is not sustainable from a healthcare quality or economic perspective. In addition to increasing costs, objective cardiac testing is associated with a substantial number of false positive and non-diagnostic tests, which lead to additional unnecessary and often invasive procedures. Implementation of accurate risk stratification care pathways designed to eliminate unnecessary cardiac testing could improve the efficiency and quality of care by decreasing false positive/non-diagnostic testing, radiation, and costs. The HEART pathway, which combines a clinical decision rule, the HEART score, and two serial troponin measurements, is a recently developed care pathway designed to identify chest pain patients for early discharge without objective testing. Primary Hypothesis: The HEART Pathway, when compared to usual care, will reduce 30 day objective cardiac testing, hospital length of stay, and cost, while maintaining patient safety. Methods: Participants (n=282) at risk for ACS will be recruited into a clinical trial from Wake Forest Baptist Medical Center (WFBMC) ED. Patients will be equally randomized to HEART Pathway or Usual Care. HEART Pathway participant's treating physician will follow HEART Pathway guidelines for identifying patients to be admitted to the hospital or observation unit for cardiac testing or to be discharged home without testing. Usual Care participant's treating physicians will decide whether the patients should be discharged home or admitted to the hospital or observation unit based on ACC/AHA guidelines without using the HEART pathway.

The HEART Pathway will be used for real time clinical decision making. Physicians will receive care recommendations according to the HEART Pathway, based on HEART score and serial cardiac biomarkers. This will help physicians identify low-risk patients for early discharge with no objective cardiac testing.

Conventional Care cardiac testing. Patients will undergo cardiac testing as determined by their treating physicians.

Objective cardiac testing (stress testing or cardiac imaging), cost, length of stay, and recurrent ED visits and non-index hospitalization for chest pain.

proportion of patients receiving any stress testing modality, coronary computed tomography angiography, or invasive catheter angiography at the index visit

Proportion of patients that are discharged from the Emergency Department without meeting the composite endpoint of index hospital admission or index objective cardiac testing

Inclusion Criteria: Age greater than or equal to 21 years Chest discomfort or other symptoms consistent with possible ACS The treating physician feels the patient could be discharged home if cardiac disease was excluded Exclusion Criteria: New ST-segment elevation in contiguous leads on any electrocardiogram (>/= 1 mV) Unstable vitals signs: symptomatic hypotension at the time of enrollment (systolic < 90 mm Hg), tachycardia (HR>120), bradycardia (HR<40), and hypoxemia (<90% pulse-oximetry on room air or normal home oxygen flow rate) Terminal diagnosis with life expectancy less than 1 year A non-cardiac medical, surgical, or psychiatric illness determined by the provider to require admission, increase risk of objective cardiac testing, or prevent immediate discharge following negative testing. Prior enrollment Incapacity or unwillingness to provide consent and comply with study procedures Non-English speaking Sub-study I & II Inclusion Criteria: ED attending physicians Exclusion Criteria: ED attending physicians who decline to participate

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