Analyzing the Role of High Sensitivity Troponin in Acute Myocardial Infarction

The research article analyzes the benefit of using high sensitivity troponin in ruling out acute myocardial infarction. The study was conducted in the emergency department of a hospital and involved patients with non-traumatic chest pain. The article discusses the findings, limitations, and analysis of the study.

Title
Analyzing the role of high sensitivity troponin in acute myocardial infarction.
Introduction
Medical science is improving and acquiring several changes for the betterment of it. A lot of
experiments on various subjects are also being done to analyze how that can be helpful in the
improvement program of it. Myocardial infarction creates one of the biggest diagnostic issues
as it requires a long procedure for the analysis and assessment process. But, a new suggested
method for the assessment of this coronary syndrome is reducing the time and improving the
whole procedure. The research article analyzes the benefit of the proposed solution and in
this paper, it will be discussed, interpreted, and analyzed how the research article is
successful in proving the fact and what are the limitations that may indicate towards a further
study.
Main theme of the research article
The time for ruling out the acute myocardial infarction has been reduced by the
higher-sensitivity troponin asses. Acute myocardial infarction is an acute coronary syndrome
and in the emergency department for chest pain patients, it has become one of the main
diagnostic issues (Akbar et al. 2017). However, at the emergency department, clinical
management of any patient not only depends on the troponin but also on the history of
patients, ECG results etc. Even, a separate study suggested that the combination of hs-cTnT
level (troponin) less than or equal to 14ng/L, physician gestalt as well as ECG can rule out
more safely (Bonaca et al. 2015). Most of the chest pain patients do not have acute coronary
syndrome and due to this, they need to undergo a lengthy assessment process that include
admission for observation, stress testing, imaging, serial troponin analyses etc. But, if

combining patients’ history or background data, ECG result and hs-cTnT level combining
together can identify patients who are having a low risk of major cardiac events and are
eligible to discharge, then this method will be very much helpful in reducing the crowd from
the emergency departments. It will also reduce hospital admission and further diagnostic
requirements which not only will assist the patients but also help in improving the entire
healthcare system. The main research article, which is being discussed in this paper
(Mokhtari et al. 2016), was aimed to evaluate the diagnostic accuracy with the suggested
combination method in the emergency departments of the hospitals in order to rule out
adverse cardiac events from the hospitals within 30 days only (Cung et al. 2015).
Investigation strategy used in the research article
In the article, an observational study has been used to assess the proposed method.
Focusing on the main target, the study was organized in the emergency department of Skåne
University Hospital of Lund, which was a territory care centre. The patients who were
presenting between February 2013 and April 2014 were involved in the observational study.
The patients from the age group of 18 years or above were involved in this study and the
patients having a communication barrier were not taken into consideration (Do et al. 2015).
All the patients, who participated in the study, had a primary symptom of non-traumatic chest
pain and hs-cTnT was ordered for them also. With the use of custom made data form,
research assistants collected the clinical data and physician assessment of the patients. All the
patients’ history and ECG result were obtained before hs-cTnT results were available. The
questionnaire was provided to the physician in order to assess whether the ECG showed signs
of acute ischemia. In the study, a separate hs-cTnT level was evaluated for the patients and a
combined hs-cTnT level with patients’ history and ECG report was also evaluated (Finkle et
al. 2014). The main task was to test if the combination method is producing an acute rule out
opportunity of all adverse cardiac events to the physicians. The study did not include patients

of age below 18 or over 65 and this selection was biased. Even, the patients with
communication barrier were also excluded.
Findings from the article
In the research article, the authors also described the primary as well as the secondary
outcome measures. The primary outcome of the study was all the major adverse cardiac
events within 30 days. The secondary outcome was all the major adverse cardiac events
without unstable angina within 30 days. All the records of the patients, from all the clinics
and diagnostic centres were obtained and the death records as well as reason of death were
also recorded for the analysis purpose. But, the records of patients were collected from inside
Sweden only. One of the biggest barriers while conducting the study was lack of clear
literature regarding optimal definition of significant troponin dynamics (Ibanez et al. 2017).
A total number of 1138 patients were involved in the observational study described by the
authors of the main research article. Among all the participants, only three patients were
excluded from the study because their ST segment elevation myocardial infarction was
missed initially. In order to get an error-free result, they were excluded from the entire study
at the primary stage. The author produced a flow diagram to describe the inclusion and
exclusion of the patients in the study. It was clear to understand why the patients were
excluded and who were included in the study from the diagram. Adverse cardiac event
outcomes for the patients were illustrated in the form of table by the authors of the research
article (Shah et al. 2015). Two criteria was set for hs-cTnT level, one of them is hs-cTnT
level less than 5ng/L and the other was hs-cTnT level less than or equal to 14ng/L. In the first
criterion, 343 patients were identified for ruling out and after the addition of non-ischemic
ECG result and non-high risk history, 332 patients were ruled out. In the hs-cTnT level was
less than or equal to 14ng/L when non-ischemic ECG results and the patients’ history were
included, 759 patients were identified to be ruled out. The authors also represented the

performance of different diagnostic strategies in the research article (Levine et al. 2016). In
the research article, there were many limitations. The authors included the patients of the
duration between 9am to 9pm of weekdays only. But, they did not include the patients of all
hours and the patients of weekends. Again, the complete observational study was organized
on the patients of a single hospital of that area. So, as a result, there were no difference
between the patients who were included and the patients who were seeking care outside of
inclusion hours. As there were a huge number of participants in the study, it was assumed that
the result found in the study would be applicable for other patients outside the hospital also.
In the study, organized by the authors, there was another limitation. All the patients, whose
ECG history was missing, were excluded from the study and this might have introduced a
bias in the selection of the participants in the study. The characteristics of the patients are
illustrated in the tabular format and along with that 30-day MACE and no Mace has also been
recorded. Number of all the patients were n=1138 and 30 day MACE for n=125 and 30 day
MACE for n=1013 has been recorded. In order to understand the complete report of 30 days
clearly, each patients’ record has been shown in another table for both of the hs-cTnT level.
From the table, it was clear that when hs-cTnT level is less than 5, cardio logical risks are
lesser. The diagnostic accuracy level of hs-cTnT level at less than 5 and less than or equal to
14 is represented in the table 3 and 4 respectively. A detailed analysis of all the patients has
been represented here. In figure 2, the diagnostic strategy, in the bar graph of negative
predictive value has been shown for both the outcome of 30 day MACE in the dark grey bars
and 30 day MACE without UA in the light grey bars. Value for 2 different outcomes was
shown in the vertical lines so the representation is detailed but complex. Again, in the study
the adjudicators were not blinded to the 0 hour hs-cTnT level and due to this, a risk of
incorporation bias was also introduced in the study (Liu et al. 2016). The main purpose of the
study which was described in the research article was to find the diagnostic accuracy for

major adverse cardiac events of a single hs-cTnT level at emergency department presentation
with as well as without the patients’ history and background, and the ECG results obtained.
The target was to differentiate the accuracy in the result in order to find if the hs-cTnT level
at ED presentation combined with patients’ history and ECG result can rule out the acute
myocardial infarction among the patients of a particular hospital where the study has been
organized.
Analysis of the paper
In the methods of measurement section of the paper, the author mentioned that there
were physicians as well as interns also involved in the methods of the study and interns were
not so much experienced for completing the strategy because it was an observational study
and huge amount of data has been recorded due to the involvement of huge number of
participants (Mueller et al. 2016). The author mentioned the patients’ characteristics in the
table form which produced detailed information. However, the results produced by the author
were quite clear as it was illustrated using tabular format and it was easy to understand for the
readers also. The 30 days outcome was clearly represented in the tabular format. The
sensitivities were shown along with the normal range which can be used as reference. But,
the diagnostic strategy which was illustrated using a bar graph was not so clear to understand.
Again, many records and data of the patients were missing, which showed the negligence of
the authority and as a result, the participants were excluded from the study to avoid erroneous
outcome and in the selection of the participants it created bias (Shah et al. 2015). The
research was completed with the observational study but it could have provided a more
accurate result if the quantitative analysis would be done. Again, statistical method of data
analysis would produce a completely error free result. In the end of the research article, the
authors came into a conclusion that in combination with ECG result and patients’ history, hs-
cTnT level less than 5ng/L identifies that 30% patients are at low risk and they do not require

further analysis or assessment of acute coronary syndrome. Those patients are suitable for
immediate discharge too. But, the image that shows the negative predictive value is not so
clearly understandable. The paper also concluded that hs-cTnT level less than or equal to
14ng/L identifies patients at a higher risk and they are in need of additional hs-cTnT testing.
However, before the clinical implementation it is important for the results to be validated
externally (Stub et al. 2015).
Conclusion
The research article produced the result that combination of hs-cTnT level and ECG
results, and patient history can be helpful in reducing the time of ruling out acute myocardial
infarction (Mokhtari et al. 2016). However, this test was done on some specific patients of a
particular hospital and the patients over the age of 65 and weekend patients were also
excluded from the research study. So, if further analysis can be done on the patients who
were excluded to get a wider amount of result this would be more helpful in the evaluation of
the research aim.

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