Log in to MyACC
High-Sensitivity Troponin and Clinical Risk Scores
Study Questions:
Does incorporating clinical risk scores in early rule out pathways for myocardial infarction (MI) using high-sensitivity troponin improve the safety of these strategies?
Methods:
In a substudy of 1,935 patients presenting with suspected MI and enrolled in the High-STEACS (High-Sensitivity Troponin in the Evaluation of patients with Acute Coronary Syndrome) trial, the authors: 1) compared the ability of the European Society of Cardiology (ESC) 3-hour and the High-STEACS (which applies a lower threshold of 5 ng/L for ruling out MI) pathways in ruling out the composite outcome of type 1 MI and cardiac death at 30 days, and 2) examined whether the addition of well-established cardiovascular risk scores (TIMI, GRACE, EDACS, and HEART) improved the negative predictive value (NPV) of these strategies.
Results:
The ESC 3-hour pathway classified 70% of patients as low risk and missed 27 events, yielding a NPV of 97.9% and a sensitivity of 89.9%, while the High-STEACS pathway classified 64.9% of patients as low risk, missing 3 events, with a resulting NPV of 99.7% and a sensitivity of 98.7%. Addition of clinical risk scores to the ESC 3-hour pathway improved the NPV to above >99%, but decreased the proportion identified as low risk to <50%. Incorporating risk scores to the High-STEACS pathway did not improve the NPV, but similarly reduced the proportion of low-risk patients to <50%.
Conclusions:
The High-STEACS pathway outperforms the ESC 3-hour pathway in ruling out type I MI and cardiac death at 30 days. Addition of clinical scores to the ESC 3-hour pathway improved its safety, but at the cost of classifying a substantially higher proportion of patients at higher risk.
Perspective:
This is a timely study, as we continue to make headway in identifying the most cost-effective and safe use for high-sensitivity troponin testing. It highlights the significant impact on safety that selection of high-sensitivity troponin threshold has, and questions the usefulness of risk scores. The High-STEACS pathway, using an initial threshold of 5 ng/L, performed well with a NPV >99% while still classifying two-thirds of patients as low risk. The lower NPV of the ESC 3-hour pathway is unsurprising, as the strategy was initially devised in the era of contemporary cardiac troponin assay, which has an upper reference limit five-fold higher than the current high-sensitivity assays. Replication of these results in multicenter studies are needed to justify adopting the High-STEACS pathway for rule out. Most importantly, we await the results of the randomized multicenter High-STEACS trial, which will determine whether incorporating high-sensitivity troponin–based rule out strategies improves outcomes.
Clinical Topics: Acute Coronary Syndromes, Prevention, ACS and Cardiac Biomarkers
Keywords: ESC Congress, ESC18, Acute Coronary Syndrome, Biomarkers, Outcome Assessment, Health Care, Primary Prevention, Risk Factors, Troponin I
< Back to Listings
