Atypical
Presentation of MI
Johnna Walker PA-S
The case…
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59 year old woman presents with chief
complaint of persistent cough and chest
congestion for 1 week.
Treated at her family doc 5 days ago with
Zithromax.
Finished the Zithromax this morning but still
not feeling well, and the cough is worse.
She also complains of midsternal discomfort
that has been lingering on for the past
week, which she attributes to the force with
which she is coughing.
Risk Factors
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SH: ½ ppd smoker for 10 years. Quit
approximately 6 months ago.
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PMH: HTN treated with 5 mg of
Lisinopril.
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FH: No history of heart disease, MI,
CAD, HTN, or CVA in family.
Physical Exam
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Vitals:
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BP: 151/69, pulse: 67, Resp: 20, O2 Sats:
98% on room air.
Appearance: In no apparent distress, not
diaphoretic. Mild coughing fits during
examination.
Lungs: Diffuse wheezing and coarse rhonchi
bilaterally. No rales heard.
Heart: RRR without murmurs.
Rest of the exam unremarkable.
So it’s just a little bronchitis,
right?
We ordered a CBC with diff.
 Also, because the patient reported
“discomfort” in her chest, likely from
coughing so much, we performed a
full cardiac workup.
 Chest X-Ray, EKG, Cardiac enzymes.
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Lab results
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CBC:
WBC 9,500 (ref range 4,200-10,200)
 RBC 4,820,000 (4,200,000-5,400,000)
 Granulocytes, lymphocytes,
monocytes, eosinophils all normal
 In other words, a completely normal
CBC.
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Lab results
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Chest X- ray:
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EKG:
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Completely unremarkable
Sinus rhythm with short PR status, left
ventricular hypertrophy with repolorization
abnormality status
“an abnormal EKG which could not rule out
inferior infarct”
Lab results
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Troponin I- 5.89 ng/ml (ref range 0.000.49)
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Creatinine Kinase- 1,023 ng/ml (ref
range 0-170)
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In other words: “crap”
Quick, page cardiology!
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Cath report showed:
Ejection Fraction: 45%
 LAD stenosis of 90%
 Proximal circumflex artery stenosis of
100%
 RCA stenosis of 90%

Myocardial infarction
(things we all know, but I
needed additional slides)
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rapid development of heart muscle necrosis
caused by an ischemic event, usually
because of a plaque rupture with a clot
formation in a coronary vessel, resulting in
blockage of the blood supply to that area
Typical symptoms: Chest pain that is
described as being tight, pressure, or
squeezing; that can radiate to the jaw, neck,
or left arm. Other symptoms: dyspnea,
anxiety, lightheadedness, diaphoresis.
MI Labs/studies
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EKG ST segment elevation > 1 mm
 Presence of new Q waves
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Cardiac enzymes Troponin I• Greatest sensitivity and specificity for MI
• Levels rise within 3-4 hours and remain elevated for 10
days
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Creatinine Kinase• CK-MB is cardiac specific
• Levels rise within 3-4 hours, peaks within 12 hours, and
returns to normal within 24-36 hours
Myocardial infarction in
women
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Research has shown that more men
than women are affected with MIs, but
recent research is showing this might
be because women have more
‘atypical’ presentations of MI and are
therefore mis-diagnosed.
So, what is this ‘atypical’
presentation you speak of?
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Women are more likely to have a prodrome
of symptoms in the month leading up to the
MI.
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Unusual fatigue
Sleep disturbances
Shortness of breath
Indigestion
Anxiety
Persistent cough
Atypical presentation of
acute MI in women
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Most frequent symptoms in women with an
acute MI:
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Shortness of breath
Weakness
Fatigue
Cold sweats
Dizziness
In fact, in a study of 515 women diagnosed with
an acute MI, chest pain was absent in 43%!!!!
McSweeney, J., Cody, M., & O’Sullivan, P. (2003). Women’s Early Warning Symptoms
of Acute Myocardial Infarction. Circulation. 108 (21), 2619-23.
What this means to us as
providers…
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As a family practitioner, how many of us
wouldn’t have done the same thing in this
case? Sounds like bronchitis, write a
prescription for an antibiotic, and move on.
What would have happened if this woman
hadn’t presented to an ED where we have
the resources to do the appropriate labs
and studies?
We have to be careful not to miss
presentations like this. Even without
warning signs, appropriate risk factors, etc,
we always have to…
… think about the zebras!
(come on, you know you’ve
missed that!)
Don’t we all…