What Does Elevated High-Sensitive Troponin I in Stroke Patients Mean: Concomitant Acute Myocardial Infarction or a Marker for High-Risk Patients

Abstract

Background: Acute ischemic stroke patients may occasionally suffer from concomitant acute coronary syndrome (ACS). Troponin I and T are established biomarkers to detect ACS. Recently introduced high-sensitive cardiac troponin (hs-TNI and hs-TNT) assays are increasingly used to identify ACS in stroke patients even without signs or symptoms of ACS. These new test systems very often detect elevated values of hs-troponin, although clinical relevance and consequences of elevated hs-TNI values in these patients are unclear so far. Patients and Methods: We examined hs-TNI values in 834 consecutive ischemic stroke patients admitted to our Comprehensive Stroke Center during a 1-year period. hs-TNI was measured immediately after admission and after 3 h if initial hs-TNI was elevated above the 99th percentile of normal values (>0.045 ng/ml). Patients with elevated values were divided into two groups: (1) constant and (2) dynamic hs-TNI values. The dynamic approach was defined as a 30% rise or fall of the hs-TNI value above the critical value within 3 h. All patients received stroke diagnostic and continuous monitoring according to international stroke unit standards, including a 12-lead ECG, blood pressure, body temperature and continuous ECG monitoring, as well as regular 6-hourly neurological and general physical examination (including NIHSS scores). The cardiologists - as members of the Stroke Unit team - evaluated clinical symptoms/examination, as well as laboratory, echocardiographic and ECG findings for the diagnosis of ACS. Results: 172/834 (20.6%) patients showed elevated hs-TNI levels on admission. Patients with elevated hs-TNI values exhibited a significantly (p < 0.001) increased rate of hypertension (89 vs. 77.2%), history of stroke (24.4 vs. 14.8%), history of coronary artery disease (65.7 vs. 34.1%), history of myocardial infarction (22.1 vs. 7.6%), heart failure (12.8 vs. 5.7%) and atrial fibrillation (44.2 vs. 23.6%). 82/136 patients showed constant and 54/136 patients dynamic hs-TNI values: among the latter, 5 patients were diagnosed with ST segment elevation myocardial infarction (STEMI) and 24 with non-STEMI (NSTEMI). Conclusion: Our data demonstrate that hs-TNI was elevated in about 20.6% of acute ischemic stroke patients but therapeutically relevant ACS was diagnosed only in the dynamic group. hs-TNI elevations without dynamic changes may occur in stroke patients without ACS due to different reasons that stress the heart. Therefore, we suppose that hs-TNI is a sensitive marker to detect high-risk patients but serial measurements are mandatory and expert cardiological workup is essential for best medical treatment and to accurately diagnose ACS in acute ischemic stroke patients.

Impact of troponin I on outcome of ischemic stroke patients

“…Furthermore, elevated troponin levels are associated with an almost 2-fold increased risk of 5-year mortality [16]. In concordance with our study several studies showed that the short-term and long-term unfavorable outcome has been associated with increased troponin levels [6,11,12,[15][16][17].…”

“…The proportion of stroke patients with cardiac troponin level increase varies in several studies from 9.73% to 20.6% [11,12,15]. However, a smaller proportion of patients had increased troponin I levels in our study probably because higher cut-off levels were used.…”

“…In their study the cut-off level for troponin I was 0.014 ng/mL [11]. Scheitz et al's study has found that the elevation of troponin T levels occurs in every seventh patients with acute ischemic stroke and is indepedently associated with poor short-term outcome measured by mRS (mRS >2) and in-hospital mortality [15]. Furthermore, elevated troponin levels are associated with an almost 2-fold increased risk of 5-year mortality [16].…”

Factors underlying elevated troponin I levels following pacemaker primo-implantation

“…"Catecholamine overload" (ref. [27][28][29] or direct mechanical damage [30][31][32][33][34][35][36][37][38][39] during skiascopy of the heart (during pacemaker implantation) can be a marker of procedure complexity and may positively correlate with troponin levels 31 . Left ventricular failure 40 , right ventricular failure [41][42][43] , or the disparity between physiological degradation of the myocardium and insufficient elimination of its fragments (renal insufficiency) (ref.…”

Hypertroponinemia, Structural Cardiac Disease, and Stroke Mortality

“…[3][4][5] Can these risk factors, such as cTn elevation and cardiac changes, influence mortality after stroke?…”