Ashwini Davison Justin Dunn Jason Mock Deepa Rangachari May 13, 2009.
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Transcript of Ashwini Davison Justin Dunn Jason Mock Deepa Rangachari May 13, 2009.
Takotsubo Cardiomyopathy versus ST-segment elevation MI
—A case seriesAshwini Davison
Justin DunnJason Mock
Deepa Rangachari
May 13, 2009
Types of TrialsControlled Study
- Randomize Control Trial (RCT) – type of scientific experiment most commonly used in testing the efficacy or effectiveness of healthcare services or technologies. With sufficient numbers, this ensures that both known and unknown
confounding factors are evenly distributed between treatment groups.
Considered the most reliable form because they eliminate spurious causality and bias.
Observational Study Cohort study - group of people who share a common
characteristic or experience within a defined period. Case Control - Studies used to identify factors that may contribute
to a medical condition by comparing subjects who have that condition with patients who do not have the condition but are otherwise similar
Case Series
Definition of Case SeriesDescriptive research study that tracks
patients with a known exposure given similar treatment or examines their medical records for exposure and outcome.
Also known as clinical seriesCan be retrospective or prospectiveSmaller number of patients than more powerful case-control or RCTs
Case SeriesProvide information when other types cannot
or should not be undertakenCase series may be confounded by selection
bias, which limits statements on the causality of correlations observed
Results of case series can generate hypotheses that could be useful in designing further studies
In this article the authors use a case series to ask the question what clinically (in the ED) can be used to differentiate Takotsubo cardiomyopathy versus ST-segment elevation myocardial infarction
Introduction to Article
Electrocardiographic ST-segment elevation: Takotsubo cardiomyopathy versus STEMI
AMERICAN JOURNAL OF EMERGENCY MEDICINE, 2009
What is Takotsubo cardiomyopathy?Also known as left ventricular apical
ballooning syndrome, ampulla CM, stress CMDevelop anginal symptoms and CHF in times
of stressExtreme: acute pulmonary edema,
cardiogenic shock
EKG & LabsST segment and/or T wave abnormalitiesSimilar to what’s seen in STEMISerum markers may be elevated
Cath & ventriculogramCatheterization: abnormal LV function, but
NORMAL coronary arteries
Diastole Systole
Diagnostic criteria (Mayo)1) transient LV apical akinesis or dyskinesis2) absence of obstructive CAD3) new EKG abnormalities in absence of
concurrent conditions
How Patients Were SelectedReviewed 12 consecutive cases of Takotsubo
CM that presented to UVA3 case excluded because of incomplete dataThen took 9 consecutive cases of STEMI for
comparison18 cases total (9 TCM, 9 STEMI)—same time
periodComparisons made between 2 groups
Demographic ResultsDescriptor Takotsubo STEMI
% that were female 89 44
Average age (years) 68.2 65.1
% with chest pain 88.9 100
% with dyspnea 55.6 77.8
% with nausea/vomiting
33.3 88.9
% with diaphoresis 55.6 100
EKG ComparisonsEKG abnormality Takotsubo STEMI
ST-segment elevation 66.7% 100%
Inferior 0 55.6
Lateral 11.1 33.3
Anterior 55.6 33.3
ST-segment depression
33.3% 77.8%
Inferior 22.2 33.3
Lateral 11.1 22.2
Anterior 0 33.3
T wave inversion 66.7% 33.3%
QT prolongation 451 ms 433 ms
Other comparisonsCXR findings were similar in both groupsInitial troponin elevation similarSTEMI peak troponin 7.34 vs TCM with 4.91EF on echo—32.7% in Takotsubo, vs 25.2% in
STEMI
DesignNot really a case series by definition—used
control group (STEMI patients)
A number of case series were published prior (all with 9 or more pts), and a systematic review published in 2006.
Appears to be a case series of Takotsubo compared with a case series of STEMIs.
StrengthsUsed consecutive patients to help reduce
selection bias in both groups (though did exclude 3 from case group)
All patients were (we assume) at the same institution
WeaknessesTime frame? Unclear how long to select
patients; also unclear how STEMI pts selected.
Too few patients—9 in each group.
No distribution of values given, no hard data—only means/percentages, no medians.
No p values or confidence intervals
Weaknesses3 people eliminated in case group for
“incomplete data”—contribute to selection bias?
No risk factors noted in either group
Unclear if any question was answered.
ConclusionsTakotsubo CM often mimics ACSAnginal chest pain with acute heart failureThis retrospective case series shows its
difficult to distinguish the 2 in the ER
Take Home MessagePhysicians need to be aware of this
alternative diagnosis to a STEMIStill need to watch for dysrhythmias &
cardiogenic shock withIdeally, if Takotsubo CM suspectedcardiac
catheterization should be chosen over fibrinolytics