Diagnostic Performance of High-Sensitivity Cardiac Troponin T Strategies and Clinical Variables in a Multisite US Cohort

Abstract

Background: European data support the use of low high-sensitivity troponin (hs-cTn) measurements or a 0/1-hour (0/1-h) algorithm for myocardial infarction (MI) or to exclude major adverse cardiac events (MACE) among Emergency Department (ED) patients with possible acute coronary syndrome (ACS). However, modest US data exist to validate these strategies. This study evaluated the diagnostic performance of an initial hs-cTnT measure below the limit of quantification (LOQ: 6 ng/L), a 0/1-h algorithm, and their combination with HEART scores for excluding MACE in a multisite US cohort. Methods: A prospective cohort study was conducted at 8 US sites, enrolling adult ED patients with symptoms suggestive of ACS and without ST-elevation on electrocardiogram. Baseline and 1-hour blood samples were collected and hs-cTnT (Roche, Basel Switzerland) measured. Treating providers blinded to hs-cTnT results prospectively calculated HEART scores. MACE (cardiac death, MI, and coronary revascularization) at 30-days was adjudicated. The proportion of patients with initial hs-cTnT measures <LOQ and risk based on a 0/1-h algorithm was determined. The negative predictive value (NPV) was calculated for both strategies when used alone or with a HEART score. Results: Among 1,462 participants with initial hs-cTnT measures, 46.4% (678/1,462) were women and 37.1% (542/1,462) were African American with a mean age of 57.6 (SD±12.9) years. MACE at 30-days occurred in 14.4% (210/1,462). Initial hs-cTnT measures <LOQ occurred in 32.8% (479/1,462), yielding a NPV of 98.3% (95%CI: 96.7-99.3%) for 30-day MACE. A low risk HEART score with an initial hs-cTnT < LOQ occurred in 20.1% (294/1,462) yielding a NPV of 99.0% (95%CI: 97.0-99.8%) for 30-day MACE. A 0/1-h algorithm was complete in 1,430 patients, ruling-out 57.8% (826/1,430) with a NPV of 97.2% (95%CI: 95.9-98.2%) for 30-day MACE. Adding a low HEART score to the 0/1-h algorithm ruled-out 30.8% (441/1430) with a NPV of 98.4% (95%CI: 96.8-99.4%) for 30-day MACE. Conclusions: In a prospective multisite US cohort, an initial hs-cTnT <LOQ combined with a low risk HEART score has 99% NPV for 30-day MACE. The 0/1-h hs-cTnT algorithm did not achieve a NPV > 99% for 30-day MACE when used alone or with a HEART score. Clinical Trial Registration: URL: https://clinicaltrials.gov Unique Identifier: NCT02984436

Implementation of the ESC 0 h/1h algorithm and the HEART score in the emergency department: A prospective cohort study

“…The recent study by Allen et al showed a NPV of 98.4% for 30-day major adverse cardiac events (MACE, defined as cardiac death, MI and revascularization) of a low HEART score in the rule-out category. This NPV was lower than the NPV in our study, which was 100% if the same definition for MACE was used [23] .…”

Rapid Exclusion of Acute Myocardial Injury and Infarction With a Single High-Sensitivity Cardiac Troponin T in the Emergency Department: A Multicenter United States Evaluation

“…A few small studies have evaluated hs-cTnT below the LoQ threshold of 6 ng/L. They often use investigational samples 18,19 or are secondary analyses from outside the United States. 20,21 Some of these studies have been inconclusive and lack an adequate gold-standard assay 18,19 for acute myocardial infarction diagnosis, including some data suggesting that a single hs-cTnT <6 ng/L may not be safe.…”

Diagnostic Performance of Serial High-Sensitivity Cardiac Troponin Measurements in the Emergency Setting

“…However, using a single low hsTn level to rule-out or discharge patients home may miss patients who are at high risk and have not reliably achieved a sensitivity ≥ 99.0%. Additional tools and laboratory tests could improve this performance (examples being HEART Score and Clinical Chemistry Score) [7,17]. Serial testing with hsTn may close this gap by identifying patients with evolving injury.…”

“…Observational studies have assessed algorithms using low and high hsTn concentrations with respective minor and 2 of 12 large differences in concentrations over a couple of hours in the emergency department (ED); these studies suggest hsTn alone may be sufficient to rule-out and rule-in MI [4,5]. However, not all studies have supported the safe rule-out or possible discharge of patients from the ED being assigned to the rule-out arms or low-risk categories with these shorter testing algorithms [6,7]. A recent randomized control trial assessing the European Society of Cardiology (ESC) 0/1 h algorithm further questions the safety of these algorithms as it did not reduce cardiovascular death or MI over the long term (2.7% composite outcome with standard protocol versus 3.3% with 0/1 h protocol; p < 0.001) [8].…”