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Three Part Question

In [adults with an apparent acute coronary syndrome precipitated by a stressful event], what are the [clinical features] that distinguish [acute myocardial infarction from stress induced cardiomyopathy]?

Clinical Scenario

A 69 year old woman presents to the emergency department patient with acute onset of chest pain and dyspnea. Symptoms began while she was attending her son’s funeral service. Her electrocardiogram shows characteristic ST-segment elevation over the anterior precordial leads with a small elevation in troponin T. While paging the cardiologist, you wonder is this patient has a myocardial infarction or stress induced cardiomyopathy (apical ballooning syndrome or Takotsubo cardiomyopathy).

Search Strategy

Medline 1946-07/14 using OVID interface, Cochrane Library (2014), PubMed clinical queries

[(Exp stress induced cardiomyopathy) OR (exp apical ballooning syndrome) OR (exp Takotsubo cardiomyopathy)] AND [exp myocardial infarction/diagnosis]. Limit to humans and English language.

Search Outcome

118 papers were identified; four were relevant to the clinical question.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Michael Falola, WIlliam Fonbah, Gerald McGwin Jr. August 2013 United States	Utilized large inpatient database, Nationwide Inpatient Sample. Inpatients aged 16 years or older with a LVABS diagnosis were compared to STEMI admissions for initial care.	Retrospective case control design comparing patients with LVABS syndrome and STEMI diagnoses	Incidence of clinical features among LVABS and STEMI patients. This study included hyponatremia as well.	Decreased incidence of traditional cardiac risk factors among LVABS patients, yet increased incidence of hyponatremia, female gender and white race among other variables compared to STEMI patients.	This is a retrospective case control study that proposes a possible cause and effect relationship between clinical features and LVABS, including hyponatremia and SIADH.
Parodi G, Del Pace S, Carrabba N, et al. January 2007 Italy	White women with hospital admission, chest pain and anterior ST-elevation acute MI referred for potential revascularization intervention.	The incidence, clinical findings and outcome of white women diagnosed with LVABS was compared to consecutive women with an anterior ST elevation myocardial infarction. Patients in both group underwent coronary angiography.	The incidence, various clinical findings and outcome of patients with chest pain and anterior ST elevation.	The incidence of LVABS was found to be 12% among patients with anterior ST elevation and chest pain, however only 2% among the entire group of acute MI patients. Ck-MB and an antecedal stressful event were found to be the only independent risk factors predictive of LVABS among patients with anterior ST elevation and chest pain.	Patient population is from a single institution which may make it less applicable to other populations. Selection bias was introduced as only admitted patients with anterior location MI that had consented to coronary angiography were included.
El-Sayed AM, Brinjiki W, Salka S, et al. November 2012 United States	Utilized large database, National Inpatient Sample. All patients diagnosed with LVABS over a one year period were included.	Retrospective case control design. Demographic and co-morbid conditions were compared with two separate control groups. First, patients with MI as a primary diagnosis and second, patients with orthopedic trauma as a primary diagnosis.	Retrospective evaluation of LVABS and co-morbid conditions in a patient population,	Patients with LVABS were less likely to have traditional cardiac risk factors including obesity, hypertension and diabetes compared to patients presenting with a MI, but were more likely to have these risk factors when compared to a random sample of patients with orthopedic injuries. Multiple other co-morbidities were measured.	Selection bias is introduced a number of ways. Only admitted patients were included, thus the control group of the orthopedic trauma patients may have been more unhealthy at baseline. Patients were matched to age as well, but LVABS is largely seen in post-menopausal patients. Data is lacking about time of diagnosis of co-morbid conditions, and reverse causation should be considered.
Cortadellas J, FIgeuras J, Llibre C, et al. 2011 Spain	All patients from a single center meeting criteria for diagnosis of LVABS and first AMI with non-significant coronary stenosis were included. Consecutive patients were admitted and these two populations were compared.	Retrospective data was collected from 2002-2005 and prospectively from 2005-2009. Thirty patients with first AMI and 45 with LVABS were ultimately included. A number of clinical features were evaluated.	Clinical features of LVABS patients were compared with clinical features in patients diagnosed with first acute MI.	Among other measured factors, LVABS patients were found to have ST elevation in a greater number of leads. Negative T waves developed in a greater proportion of LVABS patients as well. LVABS patients had a lower rate of smoking, prior angina at rest and greater physical or emotional stress at the onset.	This study includes both retrospective and prospective data. Patient population is from a single center, and data may not be widely applicable. Study population was small, which may affect results.

Comment(s)

Left ventricular apical ballooning syndrome (LVABS) also known as Takotsubo cardiomyopathy or stress induced cardiomyopathy is an increasingly recognized acute cardiac syndrome that may mimic ST-elevation acute myocardial infarction. LVABS may mimic an anterior STEMI with elevation in the precordial leads, yet has significantly lower elevation in cardiac injury markers including CK and CK-MB and lack of significant coronary stenosis. It is important to consider LVABS among women suspected of having anterior STEMI as the incidence was found to be 12% in one study. LVABS patients are more likely to be white and are overwhelmingly post-menopausal females, with hormone disequilibrium as a possible contributing factor. Clinically, LVABS patients were also found to have higher heart rates and lower ejection fractions at presentation. Patients with LVABS had significantly lower incidences of traditional cardiovascular risk factors including diabetes, tobacco use, hypertension, hyperlipidemia and obesity when compared to typical patients presenting with AMI. Common comorbidities of LVABS patients include a preceding stressful event, history of CHF, sepsis, malignancy, chronic liver disease and a history of substance abuse and anxiety or mood disorders. LVABS was also found to be associated with higher incidences of immune or endocrine disorders, a history of CVA and conditions contributing to hyponatremia or increased catecholamine production.

Clinical Bottom Line

When compared to patients presenting with typical AMI, patients with LVABS had a lower incidence of traditional cardiac risk factors and a higher incidence of preceding stressful events. Patients were also more likely to be post-menopausal women. LVABS is associated with a history of CHF, malignancy, sepsis, chronic liver disease, substance abuse, and anxiety or mood disorders among other comorbid conditions.

References

1. Michael Falola, WIlliam Fonbah, Gerald McGwin Jr. Takotsubo cardiomyopathy versus ST-elevation myocardial infarction in a large case-control study: Proposing a new mechanism International Journal of Cardiology 2013 August, 10;167(3):1079-81
2. Parodi G, Del Pace S, Carrabba N, et al. Incidence, Clinical Findings, and Outcome of Women With Left Ventricular Apical Ballooning Syndrome American Journal of Cardiology 2007, January,15;99(2):182-5
3. El-Sayed AM, Brinjiki W, Salka S, et al. Demographic and Co-Morbid Predictors of Stress (Takotsubo) Cardiomyopathy American Journal of Cardiology 2012 Nov 1;110(9):1368-72
4. Cortadellas J, FIgeuras J, Llibre C, et al. Acute cardiac syndromes without significant coronary stenosis: differential features between myocardial infarction and apical-ballooning syndrome Coronary Artery Disease 2011;22(6):435-41