Elevated troponin in acute ischemic stroke – a matter of debate?

Author: Dr. med. Antje Schmidt-Pogoda, Universitätsklinikum Münster

With respect to high prognostic relevance,¹ international guidelines recommend the measurement of troponin in all patients presenting with acute ischemic stroke.² However, high-sensitivity troponin is elevated in 20-55% of acute stroke patients,³ many of whom without thrombotic acute coronary syndrome (ACS). Therefore, the management of stroke patients with elevated troponin is a common matter of debate between neurologists and cardiologists in emergency rooms. This blog post discusses three frequent questions from the neurologist’s perspective.

Why is troponin elevated in so many acute stroke patients?

At first, acute ischemic stroke is a stressful condition, which may cause coronary demand ischemia, especially in patients with preexisting chronic heart failure, atrial fibrillation or coronary artery disease.⁴ Large strokes in particular may also induce a neurogenic heart syndrome through bursts of neurogenic sympathetic activity and catecholamine release, leading to coronary demand ischemia and myocardial necrosis.⁴ Beyond, elevated troponin in stroke patients might be attributable to nonischemic myocyte injury due to catecholamine-mediated myocardial toxicity, cytokine-mediated myocardial injury, endothelial dysfunction and microvascular spasms.⁴ Further conditions frequently associated with elevated troponin include atrial fibrillation, heart failure, pulmonary embolism, sepsis, and renal insufficiency.

Is troponin suitable to predict ACS in stroke patients?

This question was addressed by the Troponin Elevation in Acute Ischemic Stroke (TRELAS) study, which included 2123 consecutive patients presenting with acute ischemic stroke, who did not have ST-segment-elevation myocardial infarction (STEMI).⁵ Of all included patients, a subset of 29 of 291 patients with elevated troponin underwent diagnostic coronary angiography. The prevalence of coronary culprit lesions on angiography was 24%, and 21% of patients underwent revascularization.⁵ Compared to a control cohort of age- and sex-matched non-ST-segment-elevation myocardial infarction (NSTEMI) patients without stroke, the prevalence of coronary culprit lesions was lower in stroke patients.⁵ Nonetheless, coronary culprit lesions were identified in 24% of stroke patients with elevated troponin, thus demonstrating that elevated troponin should not be ignored in acute stroke patients.

What’s the ideal management of stroke patients with elevated troponin?

The recently launched Prediction of Acute Coronary Syndrome in Acute Ischemic Stroke (PRAISE) study aims to develop a diagnostic algorithm that allows the prediction of acute coronary syndrome in stroke patients with elevated troponin. For the time being, a clear recommendation for acute stroke patients with elevated troponin is lacking. The total level and the dynamic of the troponin increase may help to predict myocardial infarction,⁶ but eventually, the diagnostic work up and treatment of individual patients remains a matter of debate between neurologists and cardiologists. Most importantly, stroke severity and bleeding risk through dual platelet inhibition and anticoagulation will largely influence treatment options.

So, elevated troponin in acute ischemic stroke remains a matter of debate!

1. Batal O, Jentzer J, Balaney B, Kolia N, Hickey G, Dardari Z, Reddy V, Jovin T, Hammer M, Gorcsan J, Schmidhofer M. The prognostic significance of troponin I elevation in acute ischemic stroke. J Crit Care. 2016;31:41–47.
2. Powers WJ, Rabinstein AA, Ackerson T, Adeoye OM, Bambakidis NC, Becker K, Biller J, Brown M, Demaerschalk BM, Hoh B, Jauch EC, Kidwell CS, Leslie-Mazwi TM, Ovbiagele B, Scott PA, Sheth KN, Southerland AM, Summers DV, Tirschwell DL, American Heart Association Stroke Council. 2018 Guidelines for the Early Management of Patients With Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association. Stroke. 2018;49:e46–e110.
3. Scheitz JF, Nolte CH, Laufs U, Endres M. Application and interpretation of high-sensitivity cardiac troponin assays in patients with acute ischemic stroke. Stroke. 2015;46:1132–1140.
4. Jensen JK, Atar D, Mickley H. Mechanism of troponin elevations in patients with acute ischemic stroke. Am. J. Cardiol. 2007;99:867–870.
5. Mochmann H-C, Scheitz JF, Petzold GC, Haeusler KG, Audebert HJ, Laufs U, Schneider C, Landmesser U, Werner N, Endres M, Witzenbichler B, Nolte CH, TRELAS Study Group. Coronary Angiographic Findings in Acute Ischemic Stroke Patients With Elevated Cardiac Troponin: The Troponin Elevation in Acute Ischemic Stroke (TRELAS) Study. Circulation. 2016;133:1264–1271.
6. Agewall S, Giannitsis E, Jernberg T, Katus H. Troponin elevation in coronary vs. non-coronary disease. Eur. Heart J. 2011;32:404–411.