Article, Hyperbaric Medicine

Takotsubo cardiomyopathy: an unusual syndrome mimicking an ST-elevation myocardial infarction

on both the hypoxia tolerance of damaged tissues and the absorptive rate of oxygen bubbles. Absorption of the bigger bubbles is a difficult process, and the pathophysiology of applying HBO is to reduce the size of bubbles by the principle of the Boyle-Mariotte law. In this case, we found that the later observed symptoms, such as decreased level of consciousness and upper limb weakness, resolved com- pletely after HBO therapy. However, nerve cells are a more hypoxia-sensitive tissue than others, and prolonged expo- sure to a hypoxic environment will result in apoptotic neuronal cells. We hypothesize that multiple spinal infarc- tions had occurred before HBO therapy was performed and had already resulted in irreversible neurologic sequelae.

According to the above mechanisms, HBO can block the progression of hypoxia in tissues in such cases. There would arguably have been a better neurologic outcome if he had received earlier interruption with HBO therapy. However, some authors have nevertheless concluded that delayed HBO therapy is still beneficial even 15 to 60 hours after onset of symptoms of acute Gas embolism, suggesting that it is not too late to perform HBO treatment on such a critical patient, even if this requires transferring the patient to the nearest hyperbaric facility when none is available locally [11,12].

Te-Ming Liu MD Kuo-Chin Wu MD Ko-Chi Niu MD, PhD Hung-Jung Lin MD

Department of Emergency Medicine Department of Hyperbaric oxygen Therapy

Chi-Mei Medical Center

Yung-kang City Tainan 710, Taiwan, ROC

doi:10.1016/j.ajem.2006.05.014

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Takotsubo cardiomyopathy: an unusual syndrome mimicking an ST-elevation myocardial infarction

Coronary artery atherosclerosis and subsequent Plaque rupture are thought to be responsible for most myocardial infarctions (MIs). Recent cardiology literature, primarily describing elderly female patients, has introduced an unusual subset of patients who have ST-segment elevation anterior MI with no evidence of angiographic disease on cardiac catheterization [1-4]. These patients have profound and peculiar reversible cardiac wall motion abnormalities and dysfunction. This cardiomyopathy, coined the Takot- subo cardiomyopathy or Takotsubo syndrome in Japan because of the heart’s appearance on the end-systolic ventriculogram, is beginning to shed some light on other etiologies as suggested, contributing factors in some acute MIs, including stress, hormones, and microvascular spasm. A 77-year-old white woman presented to the emergency department (ED) via emergency medical services with severe respiratory distress. According to her husband, she became acutely dyspneic at home after a heated argument, with a subsequent decrease in her level of consciousness. Her medical history was significant for chronic obstructive pulmonary disease and coronary artery disease, with a stent apparently placed to an unknown vessel 2 years prior at a different hospital. On arrival to the ED, she was found to be in respiratory failure requiring immediate rapid sequence intubation. Her initial electrocardiogram (ECG) tracing demonstrated sinus rhythm with more than 1 mm ST elevation in leads V2 to V5 (Fig. 1). Physical examination revealed an intubated and sedated patient with blood pressure of 98/60 mm Hg, heart rate of 110, jugular venous pressure of 11 mm Hg, an S4 gallop, and bibasilar rales. A portable chest radiograph after intubation revealed flattened diaphragms consistent with emphysema and pulmonary vascular fullness, suggestive of pulmonary edema. A bedside ultrasound in the ED demonstrated anterior wall

hypokinesis and an ejection fraction of 30%.

After her intubation, she was given aspirin per orogastric tube and urgently rushed to the cardiac catheterization laboratory, where her coronary arteries were found to

Fig. 1 Electrocardiogram with ST elevations in leads V2 to V5.

be clear of significant disease. Her left ventriculogram demonstrated apical, mid-anteroseptal, mid-anterior, mid- inferoseptal, and lateral wall hypokinesis with basilar hyperkinesis, creating transient left ventricular apical ballooning, otherwise known as takotsubo cardiomyopathy (Fig. 2). The patient’s initial creatine kinase-MB and troponin T were 5.7 and less than 0.01 ng/mL, with levels peaking at 24 and 0.63 ng/mL, respectively. She was treated with furosemide, carvedilol, ramipril, and aspirin. Warfarin was added to prevent left ventricular thrombus formation. She was extubated on hospital day 2, her symptoms resolved, her pro-brain natriuretic peptide trended toward normal, and subsequent echocardiography performed 4 days after admission revealed a normal ejection fraction of 60% to 65% with grossly normal wall motion and a relaxation abnormality. The patient was discharged home at her Baseline functional status 6 days after admission.

Takotsubo cardiomyopathy is a transient cardiomyopathy characterized by marked apical hypokinesis and ballooning in the absence of significant coronary artery disease [5]. Takotsubo (tako [octopus] and tsubo [jar]) is a Japanese term for a round-bottomed, narrow-necked jar used to trap octopi in Japan (Fig. 3). Similar to this octopus jar, the heart’s appearance on a left ventriculogram in Takotsubo cardiomyopathy appears wide at the apex during end systole, with a narrowing where there is basilar hyperkinesis (Fig. 1). The exact mechanism is unknown; however, hormonal predisposition [6], an inciting stressor [1,2], and microvascular dysfunction resulting in simultaneous multi- vessel spasm [3,4,6,7] have been suggested as possible etiologies. Most patients with this condition are female. An association with an unusually long course of the left anterior descending coronary artery has also been noted [5] Until

recently, this syndrome had only been described in Asia; however, there are increasing numbers of documented case reports elsewhere in the world in non-Asian patients [1,8,9]. The typical patient presentation is an Elderly woman with mild to moderate chest pain, dyspnea, an ECG demonstrating ST-segment elevations in leads V2 through V5, and a modest rise in cardiac enzyme markers [5]. Almost invariably, the patient presenting with Takotsubo syndrome experiences some type of emotional or physical stress trigger just before the disease onset [1-3]. Some of these documentED triggers have included a surgical or medical procedure, a death in the family, panic disorder, or respiratory distress [1-3]. Echocardiography typically

Fig. 2 Left ventriculogram at end systole. Note the basilar hyperkinesis (white arrows) and left ventricular apical ballooning (black arrows).

Fig. 3 bTakotsuboQ jar.

demonstrates reversible anterior-apical hypokinesis or aki- nesis [7]. As opposed to a typical ST-elevation MI, Ogura

[10] and Inoue [11] have both documented an association of Takotsubo syndrome lacking the typical reciprocal ST depressions on the ECG. Ogura studied patients with confirmed Takotsubo cardiomyopathy compared with con- trols with anterior MI. He found that factors unique to the Takotsubo syndrome included (1) the absence of reciprocal changes, (2) absence of Abnormal Q waves, ST elevation in V4-6/V1-3 [termed sigmaSTeV(4-6)/V (1-3)] of 1 or higher, and (3) a prolonged QTc all showing a high sensitivity and specificity for diagnosing Takotsubo cardiomyopathy. Ogura determined that the combination of the absence of Reciprocal changes and a sigmaSTeV(4-6)/V (1-3) of 1 or higher had a greater specificity (100%) and overall accuracy (91%) than either criteria [10]. Inoue performed a similar comparison, further breaking down the anterior MI control group into those with culprit lesions proximal to either S1 or D1 (groups A and B) and those with culprit lesions distal to S1 and D1 (group C). In patients with Takotsubo syndrome, reciprocal ST-segment depression in the inferior leads was observed less frequently than in patients in groups A ( P b

.0001) and B ( P = .0002), and abnormal Q waves and ST-segment elevation in the inferior leads were observed more frequently than in group A or B ( P = .0007 and P =

.0057, respectively). The ECG findings in Takotsubo syndrome did not differ from those in group C [11].

Although this syndrome was considered a fairly rare entity in the cardiology community, it is being noticed more

frequently now that providers are aware of the phenomenon. One recent case series reported that approximately 2.2% of ST-elevation acute coronary syndromes presenting to a referral hospital during 2002 to 2003 were considered to be consistent with Takotsubo cardiomyopathy [12]. Com- plications associated with the cardiomyopathy include congestive heart failure, ventricular fibrillation, and death. Recurrence seems to be rare in these patients when followed for 1 to 4 years, and the prognosis seems to be favorable with supportive therapy, including diuresis, beta-blockade, angio- tensin-converting enzyme inhibition, and anticoagulation [13]. It is unknown at this time whether thrombolysis has any Therapeutic effect on this syndrome. The data to date do not support plaque rupture and subsequent thrombosis as the etiologies of Takotsubo, which seems to resolve spontane- ously with medical management alone without angioplasty or thrombolysis. Current evidence suggests thrombolytics may only be harmful in these patients, with the inherent bleeding risks of the therapy without documented benefits.

In conclusion, transient left ventricular apical balloon- ing–the Takotsubo cardiomyopathy–and an acute MI due to plaque rupture clinically present quite similarly, with ST-segment elevation, cardiac biomarker release, chest pain, and myocardial dysfunction. Key factors associated with the Takotsubo syndrome include an anterior MI pattern, established elderly-female association, and a significant stressor as a trigger. Thrombolysis does not seem to be a cure for the Takotsubo syndrome, and therefore may possibly only cause the Patient harm. These 2 cardiac disorders can only be carefully differentiated with coronary angiography. Emergency medicine physicians should be aware of this disease, especially in the setting of an elderly female patient presenting with an anterior MI pattern, no reciprocal ST-segment depressions, and a distinct stress trigger. Current cardiology literature suggest that cardiac catheterization be a definite first choice ahead of thrombo- lytics, even if a small delay in getting to the catheterization laboratory would make these interventions otherwise equal. If cardiac catheterization is unavailable or further delayed, thrombolysis must still be advocated in the acute setting because distal left anterior descending infarctions (distal to D1 and S1) have been shown to appear electrocardiograph- ically similar to Takotsubo syndrome [11] in the acute phase, and the former is still far more common and definitely amenable to thrombolytic therapy. Aside from immediate cardiac catheterization to make the diagnosis, typical medications used to treat MI such as aspirin, morphine, nitroglycerine, b-blockers, and heparin should still be initiated when patients suspected to have Takotsubo syndrome are treated in the ED.

Tom E. Kolkebeck MD Department of Emergency Medicine Wilford Hall Medical Center

Lackland Air Force Base, TX 78236, USA E-mail address: [email protected]

Casey L. Cotant MD Department of Internal Medicine Wilford Hall Medical Center

Lackland Air Force Base, TX 78236, USA

Richard A. Krasuski MD Department of Cardiology Wilford Hall Medical Center

Lackland Air Force Base, TX 78236, USA

doi:10.1016/j.ajem.2006.08.001

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phenomenon. Heart 2004;90(9):52.

  1. Ueyama T. Estrogen attenuates the emotional stress-induced Cardiac responses in the animal model of tako-tsubo cardiomyopathy. J Cardiovasc Pharmacol 2003;42(Suppl 1):S117 – 9.
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patients. Heart 2003;89(9):974 – 6.

  1. Gaspar J. Tako-tsubo syndrome (transient antero-apical dyskinesia): first case reported in Latin America and review of literature. Arch Cardiol Mex 2004;74(3):205 – 14 [Spanish].
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Anaphylaxis to topical bacitracin ointment

Bacitracin is used on a daily basis for treatment of local infections and is a popular topical antibiotic for wound prophylaxis because of its low cost and presumed low toxicity [1]. Historically, bacitracin has been thought to rarely cause Allergic reactions. In fact, most physicians are not aware of any side effects of the drug. However, in 2003, bacitracin was awarded bAllergen of the YearQ by the North American Contact Dermatology Group because its incidence of allergic

reactions increased from 1.5% in 1989 to 1990 to 9.2% in 1998 to 2000 [1]. We report a unique case of anaphylaxis to topical bacitracin ointment after application to a fresh tattoo. A 42-year-old white man with no significant medical history was brought to the ED by his spouse. On physical examination, the patient was disoriented and unable to follow commands. The Initial vital signs were the following: temperature, 96.5; heart rate, 46; respiratory rate, 14; blood pressure, 60/40; and pulse oximetry, 85%, on room air. The patient’s skin appeared flushed, with breath sounds clear to auscultation bilaterally. History obtained from the patient’s spouse revealed that the patient had a fresh tattoo placed on his anterior chest wall the night before, and approximately 10 to 15 minutes before arrival in the ED, the patient had

applied bacitracin to the tattoo.

The patient received normal saline solution, Solumedrol (125 mg), Benadryl (25 mg), Pepcid (20 mg), and 0.3 mL of 1:10,000 epinephrine intravenously. Within 10 minutes, blood pressure increased to 123/67, heart rate increased to 71, and pulse oximetry was 100% on 2 L of oxygen. After 4 hours of observation in the ED and with symptoms completely resolved, the patient was discharged home in stable condition. Bacitracin was awarded the title of Contact Allergen of the Year 2003 by the American Contact dermatitis Society because of its sensitizing capacity. It is the ninth most common allergen as of 2000 [2]. Although this is common knowledge in the specialty of dermatology, there is a paucity of reports in the emergency medicine literature. Case reports of allergic reactions to bacitracin have been reported after application to abrasions, chronic ulcers, clean surgical procedures, intraNasal packing, and even mediastinal irriga- tion with bacitracin solution in the operating room [3 – 5].

However, we present a unique case of anaphylaxis after application of bacitracin ointment to a fresh tattoo.

The widespread use of bacitracin has led to an increased recognition of allergic contact dermatitis, with a potential for even life-threatening anaphylaxis. Emergency medicine physicians need to be conscious of both immediate (IgE) and delayed (cell-mediated) reactions to bacitracin. Physi- cians and patients need to be aware of these potential serious side effects when using bacitracin on damaged skin or mucosal surfaces. With continued use of bacitracin in these circumstances, it has the potential to become the number one topical allergen in North America.

Karen Greenberg DO James Espinosa MD Victor Scali DO

Emergency Medicine Department University of Medicine and

Dentistry of New Jersey-School of Osteopathic Medicine Kennedy Health System-Stratford Division

Stratford, NJ 08084, USA E-mail address: [email protected]

doi:10.1016/j.ajem.2006.04.010