Among patients with no alternative medical explanation, a measurable yet stable high sensitivity troponin (hsTn-T) was a prognosticator for mortality, MI, and hospitalization for heart failure.
Why does this matter?
Troponin was thought to be 100% specific for MI. Of course, we have learned that other diseases such as ESRD, COPD, PE, and sepsis can cause troponin elevation as well. But what if someone presents to the ED with chest pain and unexplained, stable troponin? Does this portend badness?
A negative troponin isn't a normal troponin
This was a retrospective study of nearly 20,000 patients >25 years old in Sweden with chest pain who had a measurable but stable hsTn-T. Those with only one measurement or a positive delta troponin increase were excluded. Also, all patients with an identifiable reason for the troponin elevation (e.g. AMI, ESRD, anemia) were excluded. Patients with hsTn-T above the limit of detection but within the reference range had a 2-3 fold increased risk of mortality—both cardiovascular and non-cardiovascular. They were also at increased risk for MI and heart failure admissions. As hsTn-T increased above the reference limit, so did mortality; i.e. the higher the troponin, the greater the risk for bad outcome. These patients are at increased intermediate to long-term risk and should be followed up for evaluation of important subclinical disease. The accompanying editorial suggests starting with an echo.
- Stable High-Sensitivity Cardiac Troponin T Levels and Outcomes in Patients With Chest Pain. J Am Coll Cardiol. 2017 Oct 31;70(18):2226-2236. doi: 10.1016/j.jacc.2017.08.064.
- Time for a New Strategy for High-Sensitivity Troponin in the Emergency Department. Editorial: J Am Coll Cardiol. 2017 Oct 31;70(18):2237-2239. doi: 10.1016/j.jacc.2017.09.021.
Peer review and substantive contribution by Thomas Davis, MD.