Introduction: High sensitivity troponin T (hs-TnT) are more sensitive than prior assays to evaluate patients for acute coronary syndrome. To date, hs-TnT utilization in the outpatient setting is not well described. Methods: We identified outpatient hs-TnT tests ordered at a large medical center in the first 9 months of implementation (April-December 2018). Charts were reviewed by physicians to identify patient characteristics, specialty of ordering provider, reason for ordering hs-TnT, and clinical action taken. Using unadjusted two-sample t-tests, we compared the proportion of patients referred to the ED between patients with hs-TnT levels ≥99 th % sex-specific cutoffs (≥15 ng/dL men, ≥10 ng/dL women) versus those with either undetectable hs-TnT or detectable <99 th % (control group). Results: About 100 hs-TnT outpatient tests were ordered. Patients had mean age of 66 years, 53% were male; 30% had coronary artery disease, and 12% had left ventricular ejection fraction ≤40%. Most orders were placed by cardiologists (n=58) followed by primary care physicians (n=30). The top chief complaints were dyspnea (n=38) and chest pain (n=33). Of all hs-TnT samples, 27% were undetectable, while mean detectable hs-TnT level was 38.8 ng/L, of which 57% were ≥99 th %. About 25% of patients had chronic cardiovascular conditions (like heart failure) but were asymptomatic at the time of the test. Among symptomatic patients (n=75), 31% were sent home, 28% to stress test, and 16% to the ED. Patients with hs-TnT ≥99 th % were 4.6 times more likely (95% CI 1.1-19.5, p=0.04) to be referred to the ED, compared to control. Conclusions: This is the first study describing outpatient utilization of the novel hs-TnT assay in the U.S. Despite the lack of consensus on diagnosing cardiac ischemia in outpatient clinics, providers are ordering hs-TnT in this setting - and hs-TnT values seem to influence their decision to triage patients to the ED. Our results highlight the need to standardize the implementation of hs-TnT for outpatient evaluation of cardiac ischemia. Providers are also collecting hs-TnT among asymptomatic patients with heart disease unrelated to ischemia. This suggests that novel uses of hs-TnT may emerge to monitor and prognosticate chronic cardiovascular conditions. Figure. Patient Triage based on Elevation in Outpatient hs-TnT Level