Association of Early Noninvasive Cardiac Stress Testing With Acute Myocardial Infarction and Mortality

Area of Science:

• Cardiology
• Emergency Medicine
• Health Services Research

Background:

• Acute coronary syndrome (ACS) evaluations are common, high-risk emergency department (ED) presentations.
• Following the exclusion of acute myocardial infarction (MI), early noninvasive cardiac testing (within 72 hours) is frequently employed.
• The association between early testing and patient outcomes requires further investigation.

Purpose of the Study:

• To evaluate the association between early noninvasive cardiac testing and the composite risk of death or acute MI in ED patients with suspected ACS.
• To analyze this association across different risk strata defined by the HEART score.

Main Methods:

• A retrospective cohort study design was utilized, including adult patients from October 2015 to December 2020 in whom MI was ruled out.
• The HEART risk score (History, ECG, Age, Risk factors, Troponin) was calculated to stratify patients into low, intermediate, and high-risk groups.
• Propensity score analysis assessed the association between noninvasive testing within 3 days of ED visit and 1-year composite risk of death/acute MI.

Main Results:

• The study included 174,917 patients: 61% low-risk, 36% intermediate-risk, and 3% high-risk.
• Early noninvasive testing demonstrated a risk reduction in death/acute MI of -1.54% (NNT=65) for low-risk, -4.93% (NNT=20) for intermediate-risk, and -8.98% (NNT=11) for high-risk patients.
• The percentage of patients receiving early noninvasive testing varied by risk group (5% low, 18% intermediate, 23% high).

Conclusions:

• Early noninvasive cardiac testing is associated with a reduced risk of 1-year death or acute MI.
• This benefit was observed across all risk groups, including low, intermediate, and high-risk patients.
• The findings support the utilization of early noninvasive testing in the management of patients with suspected ACS after MI exclusion.