• Users Online: 96
  • Print this page
  • Email this page

Table of Contents
Year : 2020  |  Volume : 6  |  Issue : 2  |  Page : 75-79

Clinical indications for requesting high-sensitivity troponin I in the emergency department

1 King Saud Bin Abdulaziz University for Health Sciences, COM-WR; Department of Cardiology, Ministry of National Guard Health Affair, King Abdullah, International Medical Research Center, Jeddah, Saudi Arabia
2 King Saud Bin Abdulaziz University for Health Sciences, COM-WR, Jeddah, Saudi Arabia
3 King Saud Bin Abdulaziz University for Health Sciences, COM-WR; Department of Emergency, Ministry of National Guard Health, Riyadh, Saudi Arabia

Date of Submission27-Dec-2019
Date of Decision13-Feb-2020
Date of Acceptance02-Mar-2020
Date of Web Publication11-Jun-2020

Correspondence Address:
Dr. Abdulhalim Jamal Kinsara
Department of Cardiology, Ministry of National Guard Health Affair, King Abdullah International Medical Research Center, King Saud Bin Abdulaziz University for Health Sciences, COM-WR, Jeddah
Saudi Arabia
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/IJCA.IJCA_65_19

Get Permissions


Objectives: The aim of this study is to evaluate the presenting symptoms, risk factors and cardiac origin of high-sensitivity troponin I (Hs-TnI), the tendency of emergency physicians to use Hs-TnI in a general emergency room (ER) and the validity of requesting an Hs-TnI routinely. Methodology: A retrospective cohort study with 904 patients presenting at a tertiary hospital ER with an Hs-TnI requested. The study was conducted for 15 months. Results: Of the sample, 20.4% (n = 184) presented with dyspnea, 18.03% (n = 163) with chest pain and a small proportion (12.94%, n = 117) with epigastric abdominal pain. Patients presenting with chest pain and a history of dyslipidemia were at a higher risk of developing acute coronary syndrome compared to the group without dyslipidemia (relative risk [RR] = 1.62 [1.01–2.58] P = 0.044). Diabetes and hypertension were the most prevalent chronic comorbidities in patients with dyspnea with a risk of (RR = 5.19 (0.68–39.27) P < 0.068). Patients who presented with epigastric pain and had a history of dyslipidemia had a risk of (RR = 5.23 (1.33–20.54) P = 0.009). Conclusion: The presenting symptoms should be taken into consideration by the emergency department physician to support the request for an Hs-TnI laboratory test. The yield and risk were both low in random screening.

Keywords: Chest pain, myocardial infarction, myocardial ischemia, troponin I

How to cite this article:
Kinsara AJ, Taher ZA, Altalhi A, Mahdi M, Aldainy A, Alqubbany A, Darwish A. Clinical indications for requesting high-sensitivity troponin I in the emergency department. Int J Cardiovasc Acad 2020;6:75-9

How to cite this URL:
Kinsara AJ, Taher ZA, Altalhi A, Mahdi M, Aldainy A, Alqubbany A, Darwish A. Clinical indications for requesting high-sensitivity troponin I in the emergency department. Int J Cardiovasc Acad [serial online] 2020 [cited 2020 Sep 25];6:75-9. Available from: http://www.ijcva.com/text.asp?2020/6/2/75/286459

  Introduction Top

Despite advances in the diagnosis of acute myocardial infarction (AMI), it remains the leading cause of mortality globally. Rapid medical intervention in this life-threatening disease is of the utmost importance. Patients with typical AMI present with chest pain and exertional dyspnea. However, many patients present with atypical symptoms, which might confuse clinicians and lead to a wrong diagnosis such as heartburn, acid reflux, and esophagitis. Literature reports that the proportion of AMI patients misdiagnosed ranges from 2% to 6%.[1],[2],[3] Approximately 26% of the misdiagnosed patients die within 3 days after hospital discharge compared to 12% after hospitalization.[4]

Clinicians could rule out acute coronary syndrome (ACS) after a detailed history, physical examination, and initial investigation. However, patients with atypical symptoms, fewer risk factors, and an atypical age at presentation are more likely to be misdiagnosed.[2],[5] A bedside electrocardiogram (ECG) is an efficient tool to support the diagnosis of AMI, but the ECG may be normal initially. A study reported that 62% of patients with a missed AMI diagnosis had a completely normal ECG.[4] A reliable clinical indicator can assist the clinician to exclude AMI.[6]

Laboratory tests have long been used for the detection and diagnosis of AMI. The classical cardiac enzymes have been replaced by a more sensitive and specific test to diagnose AMI, high-sensitivity troponin I (Hs-TnI). Hs-TnI levels are used daily for the diagnosis and risk stratification of coronary arterial disease (CAD).[7] However, a high troponin level is not always due to CAD. Elevated levels are also found in conditions not associated with CAD, for example, pulmonary embolism, septic shock, acute heart failure, as well as iatrogenic causes such as cardiotoxic drugs.[8]

Nearly 6 million Emergency Department (ED) admissions in the United States present with chest discomfort or symptoms suggestive of CAD, but the majority have noncardiac causes for their symptoms, such as musculoskeletal pain.[9],[10],[11] It is challenging for physicians, especially in an ED setting, to know when to request an Hs-TnI. Requesting unnecessary Hs-TnI tests will increase the cost burden on the hospital as well as increasing the diagnostic and management dilemma. The objective of the study was to evaluate the tendency of emergency physicians using Hs-TnI in emergency room (ER).

  Methodology Top

Study design

A retrospective cohort study was performed at the ED, King Abdulaziz Medical City, Jeddah, with patients referred to Cardiac Services. The study was approved by the Institutional Review Board of King Abdullah International Medical Research Center, Jeddah, Saudi Arabia, No 18/124/J.

The study was a retrospective cohort study. The patients were selected using a nonprobability sampling technique, convenience sampling. All patients who presented at the ED for any reason for whom the ED physician requested at least one Hs-TnI laboratory test from January 2017 to April 2018 and older than 18 years were included in the study. Any patients with a previous cardiac event or insufficient reported data were excluded from the study. There were 20,735 troponin requests in the sample. The standard sample size formula (n = N × X/[X + N − 1]) was used to determine representative sample size for this population, and 1035 cases were randomly selected for data collection. Patients who met the inclusion and exclusion criteria were enrolled, and the sample size realized as 904 cases (CI 95% ±3.19) [Figure 1]. Data were collected from the electronic healthcare information system used in the hospital, Best Care 2.1, and entered in a Microsoft Office Excel sheet. Patient's demographic profile, risk factors including dyslipidemia, hypertension, and diabetes mellitus, Hs-TnI, chief complaint and final diagnosis were collected. There were little family-related history available in the medical record, and we omitted family history from our data collection sheet. An Hs-TnI result was considered positive if ≥120 mmol/L. We used the “ARCHITECT STAT Hs-TnI” kit to measure the troponin I level. A diagnosis of ACS was established based on the clinical features as well as the ECG finding. An ED physician interpreted both results. The diagnosis of MI was confirmed by a coronary angiogram.
Figure 1: Study flow chart

Click here to view

Simple descriptive statistics were used to describe the demographic profile of the sample. Mean and standard deviation was used for quantitative variables, with frequency, percentage, and interquartile range for qualitative data.

Based on the presenting symptom, the participants were categorized into three groups. The first group included patients with acute chest pain, the second, patients presenting with dyspnea, and the third, patients with epigastric pain. The patient characteristics and diagnoses were analyzed for each group.

Inferential analysis was performed to compare the three groups to find any clinical or statistical significance. SPSS version 19 (SPSS version 19; IBM Corp., Armonk, New York, USA) was used for the analysis. Chi-square test was used for each variable and t-test for quantitative variables. A value of P ≤ 0.05 was deemed statistically significant.

  Results Top

Of 20,735 h-TnI request in the study period, a sample of 1035 was included in the study, of which 904 (87.34%) were eligible for the study. The reasons for exclusion were incomplete clinical data and the Hs-TnI requested after transfer from the ED. The male participants in our sample size were 619 (68.47%). The mean age was 60.86 ± 19.52, and the average body mass index 28.52 ± 8.44 kg. More than half of the cases were diabetic 531 (58.73%), 557 (61.61%) were hypertensive, and 208 (23.0%) were dyslipidemic [Table 1]. The main presenting symptoms associated with the Hs-TnI request in the ED were dyspnea (n = 184, 20.35%), chest pain (n = 163, 18.03%), and epigastric pain (n = 117, 12.94%) [Table 1].
Table 1: Patient demographics

Click here to view

A small proportion of the candidate had a positive Hs-TnI (n = 125, 13.82%) with the first request. The diagnosis of ACS accounted for 70 (7.72%) person of the study participants, followed by heart failure (n = 38, 4.20%) and a motor vehicle accident (MVA) (n = 34, 3.76%) [Table 1]. The proportion of 7.72% of all patients with an Hs-TnI request reflects a high tendency of ER physicians to overuse Hs-TnI even in a low-risk patient. Moreover, none of the patients presenting due to MVA were diagnosed with ACS with no chest pain or ECG changes.

In patient who had troponin requested for them, chest pain was a presenting symptom only in 163 (18.03%) patients. Forty-eight (29.44%) of them diagnosed later with ACS. 39 (17.48%) patients presented with chest pain combined with dyspnea. 11 (28.20%) of the presentation of the last subgroup were due ACS. Participants who had dyslipidemia and presented with chest pain were at a higher risk of developing ACS compared to the subgroup without dyslipidemia (relative risk [RR] = 1.62 [1.01–2.58]; P = 0.044) [Table 2].
Table 2: Data statistical analysis, the relative risk of developing acute coronary syndrome for the patient with these presenting symptoms and comorbidities compared to those who just presented in the emergency department with the presenting symptoms without associated comorbidities

Click here to view

In the second group who had troponin requested, 184 (20.35%) patients presented with dyspnea. 12 (6.52%) of them was secondary to ACS. Patients presenting with dyspnea as the primary symptom of symptom of ACS were older and more likely to have diabetes and hypertension with a risk of (RR = 5.19 [0.68–39.27]; P = 0.068) and dyslipidemia with a risk of (4.11 [1.40–12.00] P = 0.006) [Table 2].

In the third group who had troponin requested, epigastric pain was the presenting symptom in 117 (12.94%) persons. The epigastric pain of a small proportion of this group (n = 12, 10.25%) was justified by ACS. The age ranged from 49 to 82 years, which is relatively wider than the age range of other presentations. The risk of ACS in a patient who presented with epigastric pain associated with diabetes was (RR = 4.60 [0.58–36.15]; P = 0.104), epigastric pain associated with hypertension was (RR = 3.97; [0.50–31.19]; P = 0.148), and epigastric pain combined with dyslipidemia (RR = 5.23 [1.33–20.45]; P = 0.009) [Table 2].

We further studied the patients whose Hs-TnI results were ≥120 mmol/L and presented with unusual ACS presentation; however, they ended up with ACS. The group who presented with chest pain had a risk of (4.16 [2.65–6.54]; P < 0.001) to be diagnosed with ACS and dyspneic patients were at risk of (9.87 [3.16–30.75]; P < 0.001) of developing ACS. Finally, patients with epigastric pain were at a risk of (26.00 [5.89–114.73]; P < 0.001) developing ACS [Table 2].

The sample size of patients who presented with other clinical features such as palpitations, syncope, abdominal pain, back pain, and chest tightness was too small for the statistical analysis.

  Discussion Top

In this retrospective cohort study investigated 904 patients who were admitted to a tertiary hospital ER with an Hs-TnI requested. Of the sample, 20.4% (n = 184) presented with dyspnea, 18.03% (n = 163) with chest pain and a small proportion (12.94%, n = 117) with epigastric abdominal pain. Patients presenting with chest pain and a history of dyslipidemia were at a higher risk of developing ACS compared to the group without dyslipidemia. Diabetes and hypertension were the most prevalent chronic co-morbidities.

It was noted in a previous article that one-third of AMI patients did not complain of chest pain.[12] Their second-most frequent presenting symptom was dyspnea followed by diaphoresis, nausea, and syncope.[13]

The atypical presentations were observed in patients older than 67 years and patients with comorbidities, similar to findings in the literature confirming that the elderly, women, DM, and patients with a history of heart failure usually presented with vague symptoms.[14],[15] On average, they are 7-year-older than other patients, 80% is diagnosed with coronary artery disease and presented with an atypical and confusing picture due to the comorbidities and complaints related to this age group.[16],[17]

As expected, chest pain and dyspnea were the two most frequent presenting symptoms, and these symptoms should be considered as baseline risk factors. Some risk factors can change the presentation of the patient, for example, diabetic patients are more likely to present without chest pain,[18] and an ECG is critical for a diagnosis.

A systematic review reported that requesting an Hs-TnI in a patient with chronic heart failure provides a prognostic stratification and is a reliable predictor of cardiovascular mortality.[19] An increase in the Hs-TnI level in sepsis has been investigated and linked to left ventricular dysfunction with a poor outcome. The release in troponin is due to the loss of membrane integrity with troponin leakage or microvascular thrombotic injury.[20]

The setting for the current study is also a trauma center, close to a highway, admitting a high proportion of MVA cases. A literature review reported no benefit in the routine request for Hs-TnI or troponin for all MVA victims. The recommendation was to limit requests to patients with polytrauma or chest trauma. Knowing the level of Hs-TnI in other MVA cases did not support a diagnosis or health-care management.[21],[22],[23] The multiple causes of elevated Hs-TnI caused reservations about its specificity for the cardiac-related disease. To differentiate between cardiac and noncardiac increased troponin levels, new terms describing Hs-TnI of noncardiac origin such as troponitis, troponin leak, and Type 2 AMI were developed.[24]

Two limitations should be considered for the study, the sample was obtained from the ED alone, and due to the proximity of the highway, there may have been a higher proportion of MVA-related ED admissions, possibly resulting in selection bias.

  Conclusion Top

A request for troponin should depend on a combination of symptoms and risk factors. Atypical symptoms in the elderly, diabetic, or hypertensive patients, especially patients presenting with dyspnea, should be considered. Routine screening is not justified and does not improve patient outcome.

The data used to support the findings of this study are restricted by the King Abdullah International Medical Research Center Institution Review Board to protect PATIENT PRIVACY. Data are available from the Institutional Review Board irb@ngha.med.sa or via the corresponding author, for researchers who meet the criteria for access to confidential data.

The study did not receive specific funding but was performed as part of the employment of the authors, at King Saud bin Abdulaziz University for Health Sciences.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Pope JH, Aufderheide TP, Ruthazer R, Woolard RH, Feldman JA, Beshansky JR, et al. Missed diagnoses of acute cardiac ischemia in the emergency department. N Engl J Med 2000;342:1163-70.  Back to cited text no. 1
Lee TH, Goldman L. Evaluation of the patient with acute chest pain. N Engl J Med 2000;342:1187-95.  Back to cited text no. 2
Schor S, Behar S, Modan B, Barell V, Drory J, Kariv I. Disposition of presumed coronary patients from an emergency room. A follow-up study. JAMA 1976;236:941-3.  Back to cited text no. 3
Lee TH, Rouan GW, Weisberg MC, Brand DA, Acampora D, Stasiulewicz C, et al. Clinical characteristics and natural history of patients with acute myocardial infarction sent home from the emergency room. Am J Cardiol 1987;60:219-24.  Back to cited text no. 4
Rusnak RA, Stair TO, Hansen K, Fastow JS. Litigation against the emergency physician: Common features in cases of missed myocardial infarction. Ann Emerg Med 1989;18:1029-34.  Back to cited text no. 5
Lee TH, Cook EF, Weisberg M, Sargent RK, Wilson C, Goldman L. Acute chest pain in the emergency room. Identification and examination of low-risk patients. Arch Intern Med 1985;145:65-9.  Back to cited text no. 6
Samman Tahhan A, Sandesara P, Hayek SS, Hammadah M, Alkhoder A, Kelli HM, et al. High-sensitivity troponin I levels and coronary artery disease severity, progression, and long-term outcomes. J Am Heart Assoc 21;7(5). pii: e007914. doi: 10.1161/JAHA.117.007914.  Back to cited text no. 7
Hamm CW, Giannitsis E, Katus HA. Cardiac troponin elevations in patients without acute coronary syndrome. Circulation 2002;106:2871-2.  Back to cited text no. 8
Bahrmann P, Bertsch T, Sieber CC, Christ M. Management of patients with chest pain presenting to the emergency department: In need for the implementation of the 1 h rapid rule-out algorithm using high-sensitivity troponin I assays in clinical practice. Ann Transl Med 2016;4:18.  Back to cited text no. 9
Hollander JE, Robey JL, Chase MR, Brown AM, Zogby KE, Shofer FS. Relationship between a clear-cut alternative noncardiac diagnosis and 30-day outcome in emergency department patients with chest pain. Acad Emerg Med 2007;14:210-5.  Back to cited text no. 10
Thygesen K, Mair J, Katus H, Plebani M, Venge P, Collinson P, et al. Recommendations for the use of cardiac troponin measurement in acute cardiac care. Eur Heart J 2010;31:2197-204.  Back to cited text no. 11
Canto JG, Shlipak MG, Rogers WJ, Malmgren JA, Frederick PD, Lambrew CT, et al. Prevalence, clinical characteristics, and mortality among patients with myocardial infarction presenting without chest pain. JAMA 2000;283:3223-9.  Back to cited text no. 12
Cervellin G, Rastelli G. The clinics of acute coronary syndrome. Ann Transl Med 2016;4:191.  Back to cited text no. 13
Nawar EW, Niska RW, Xu J. National hospital ambulatory medical care survey: 2005 emergency department summary. Adv Data 2007;(386):1-32.  Back to cited text no. 14
Nikus K, Pahlm O, Wagner G, Birnbaum Y, Cinca J, Clemmensen P, et al. Electrocardiographic classification of acute coronary syndromes: A review by a committee of the international society for holter and non-invasive electrocardiology. J Electrocardiol 2010;43:91-103.  Back to cited text no. 15
Writing Group Members, Mozaffarian D, Benjamin EJ, Go AS, Arnett DK, Blaha MJ, et al. Heart disease and stroke statistics-2016 update: A report from the American heart association. Circulation 2016;133:e38-360.  Back to cited text no. 16
Canto JG, Fincher C, Kiefe CI, Allison JJ, Li Q, Funkhouser E, et al. Atypical presentations among medicare beneficiaries with unstable angina pectoris. Am J Cardiol 2002;90:248-53.  Back to cited text no. 17
Faerman I, Faccio E, Milei J, Nuñez R, Jadzinsky M, Fox D, et al. Autonomic neuropathy and painless myocardial infarction in diabetic patients. Histologic evidence of their relationship. Diabetes 1977;26:1147-58.  Back to cited text no. 18
Aimo A, Januzzi JL Jr., Vergaro G, Ripoli A, Latini R, Masson S, et al. Prognostic value of high-sensitivity troponin T in chronic heart failure: An individual patient data meta-analysis. Circulation 2018;137:286-97.  Back to cited text no. 19
Maeder M, Fehr T, Rickli H, Ammann P. Sepsis-associated myocardial dysfunction: Diagnostic and prognostic impact of cardiac troponins and natriuretic peptides. Chest 2006;129:1349-66.  Back to cited text no. 20
Tan J, Thiagarajan S, Schultz C, Sudhakar R, Hillis G, Marangou J. Assessment of Cardiac Contusion in Motor Vehicle. Heart, Lung and Circulation Accident Patients 2017;26:S102-3.  Back to cited text no. 21
Lippi G, Buonocore R, Mitaritonno M, Cervellin G. Cardiac troponin I is increased in patients with polytrauma and chest or head trauma. Results of a retrospective case-control study. J Med Biochem 2016;35:275-81.  Back to cited text no. 22
Mahmood I, El-Menyar A, Dabdoob W, Abdulrahman Y, Siddiqui T, Atique S, et al. Troponin T in patients with traumatic chest injuries with and without cardiac involvement: Insights from an observational study. N Am J Med Sci 2016;8:17-24.  Back to cited text no. 23
Collinson P. Troponin measurement in patients with suspected acute coronary syndromes: Walking beyond the wall. Eur Heart J Qual Care Clin Outcomes 2018;4:8-9.  Back to cited text no. 24


  [Figure 1]

  [Table 1], [Table 2]


    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

  In this article
Article Figures
Article Tables

 Article Access Statistics
    PDF Downloaded35    
    Comments [Add]    

Recommend this journal