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Arch Gen Intern Med 2017 | Volume 1 Issue 3
allied
academies
International Conference on
FAMILY MEDICINE AND FAMILY PHYSICIANS
October 16-17, 2017 | Toronto, Canada
patient in septic shock may be detrimental. Clinicians dealing
with an abnormal troponin result, even when the patient’s
presentation is not consistent with coronary thrombosis, often
feel compelled to order additional cardiac tests and services,
adding to the overall cost of care. Elevated troponin levels in
suchpatientsmay lead to invasive cardiac procedures. In a study
of patients with an elevated troponin and subsequent normal
coronary angiograms, 28% had tachycardia, 10% pericarditis,
5% heart failure, 10% strenuous exercise, and 47% had no clear
precipitating event.8
The practice of obtaining a troponin level before assessment
of the patient deserves special mention. It runs counter to
what most of us learned in our training, and contrary to good
medical practice. It remains advisable to take a history, perform
a physical examination, and then order appropriate studies.
Indiscriminate troponin testing is an international finding: in a
study from the U.K. at a National Health Service hospital, 28% of
the troponin requests were deemed “completely irrelevant.” 7
These were ascribed to “tick box” practice in the triage setting
prior to a clinical assessment. When educational interventions
were done on how to improve troponin requests and when to
do so, this percentage decreased to 15%. In a busy emergency
department, with its mandates to both turn patient census over
quickly, and to not miss a patient having an acute myocardial
infarction or unstable angina, it is understandable why
indiscriminate ordering of a troponin level may be favoured.
Also, in intensive care units a troponin may be requested
for a sick patient who is poorly communicative.3 Yet in our
pursuit of quickly recognizing acute coronary syndrome, giving
patients that diagnosis when they do not have it is an undesired
outcome. The routine practice of requesting a troponin as part
of a bundled lab set should be re-examined.
A strategy for improved troponin use is to perform a history
(with attention to cardiac risk factors), a physical exam, and a
review of the ecg in order to put abnormal troponin results in
the appropriate clinical context and avoid diagnostic confusion
and malfeasance.2-5 In some cases an echocardiogram to
detect leftventricularwallmotion abnormalities adds additional
value. I offer three examples of patients with positive troponin
results due to non-thrombotic causes where this strategy was
helpful: 1) a 55 year old man with colon cancer presented
to the emergency department with dizziness after two days
of severe bleeding per rectum. He had sinus tachycardia,
hypotension, and his hematocrit was 16%; 2) A 36 year old
woman being treated for acute myelogenous leukemia on
the oncology service developed atrial fibrillation with a fast
ventricular response; her platelet count was severely low; the
electrocardiogram did not suggest infarction or ischemia; 3) An
86 year old man was admitted to the intensive care unit with
a temperature of 400 Celsius, septic shock, and renal failure.
Cardiology consultation in such cases, if desired, may indeed
aid the referring caregivers in sorting out the cause of the
troponin elevation and can provide not only a clinical but also an
educational service. It is recognized that an elevated troponin
level in patients not having an acute coronary syndrome is an
indication of illness severity and predicts mortality. This is an
ongoing area of research.2-5
In clinical medicine we often like to refer to Occam’s razor and
the utility in finding one cause or diagnosis that accounts for
the patient’s presenting signs and symptoms. There will always
be dynamic tension between Occam and Hickam, who stated
“patients can have as many diseases as they……please.”9
The concern here is indiscriminant ordering of today’s highly
sensitive troponin assays dulls Occam’s razor and renders
it sorely in need of sharpening. We should avoid “check the
box” or “click on the test” ordering of troponin levels without
first doing an assessment of the patient. If however an
indiscriminate troponin assay is abnormal it behooves us to
put it in clinical context before ordering unnecessary tests,
medicines, and procedures. When elevated troponin levels are
present in patients admitted for non-cardiac reasons, and the
probability of myocardial ischemia due to coronary thrombosis
is low, evaluation and treatment should be directed towards the
primary diagnosis. We, and our patients, can ill afford to do
otherwise.
Speaker Biography
Gregory D. Chapman, MD, FACC is a Professor of Medicine/Cardiovascular Disease
at the University of Alabama at Birmingham. He has published commentaries and
research papers in The New England Journal of Medicine, Circulation, the American
Journal of Cardiology, and the American Journal of Medicine. He is now in his third
decade of practice as a cardiologist, with experience in academic and private practice
settings. His interests include STEMI recognition and treatment, as well as the diagnosis
of acute coronary syndromes and their mimics. In addition to an active clinical role, he
enjoys teaching residents in internal medicine, emergency medicine, and cardiology.
e:
gchapman@uabmc.edu