High-Sensitivity Troponin: Finding a Meaningful Delta

Abstract

High-sensitivity cardiac troponin (hs-cTn) assays have significantly refined the resolution of biomarker-level detection and have emerged as the gold standard cardiac biomarker in evaluating myocardial injury. Since its introduction, hs-cTn has been integrated into the Fourth Universal Definition of Myocardial Infarction and various European Society of Cardiology (ESC) and American College of Cardiology/American Heart Association (ACC/AHA) guidelines for the evaluation and diagnosis of chest pain syndromes. However, despite its integral role in caring for patients with chest pain, there are still substantive gaps in our knowledge of the clinical interpretation of dynamic changes in hs-cTn values. Whether a relative or absolute hs-cTn delta should be used to detect acute myocardial injury remains debatable. There are also emerging considerations of possible sex and racial/ethnic differences in clinically significant troponin deltas. In the emergency department, there is debate about the optimal time frame to recheck hs-cTn after symptom onset for myocardial infarction rule-out and whether hs-cTn deltas should be integrated into clinical risk scores. In this review, we will provide an overview of the history of clinical utilization of cardiac biomarkers, the development of hs-cTn assays, and the ongoing search for a meaningful delta that can be clinically applicable.

Keywords: cardiac biomarkers; high-sensitivity cardiac troponin; troponin delta.

Figure 1

Clinical challenges in troponin delta interpretation. A summary of the definitions of acute and chronic myocardial injury, and some of the various clinical challenges associated with interpreting high-sensitivity cardiac troponin (hs-cTn) deltas.

Figure 2

Advantages and drawbacks of absolute delta criteria versus percent rise criteria for high-sensitivity troponin. High-sensitivity serum troponin values were previously below the limit of detection in earlier generation assays. There has been a shift to using absolute delta criteria instead of percent rise criteria. For a given patient who develops chest pain at 12:00, depending on the window of time along his/her presentation to the ED, the progression from the first to second measured values of serum troponin may meet the absolute value criteria but not meet the percent rise criteria. Abbreviations: %ile: percentile; ED: emergency department; ESKD: end-stage kidney disease; hs-cTn: high-sensitivity cardiac troponin; MI: myocardial infarction.