Discussion
Takotsubo cardiomyopathy is an acute, stress-induced cardiomyopathy that was first described in Japan in the early 1990s.5 It is thought to be due to catecholamine-induced dysfunction from a stressful event,6-8 such as the death of a loved one, which is why it is often referred to as “broken heart syndrome.” However there are case reports highlighting other causes of Takotsubo cardiomyopathy, such as cocaine use,9 scuba diving,10 and diabetic ketoacidosis combined with hypothermia.11
Patients with Takotsubo cardiomyopathy will frequently have ECG abnormalities, including ST-segment elevation or depression, or T-wave changes; troponin levels also may be elevated. The majority of patients (>80%) are postmenopausal women, typically aged 50 to 75 years.6,12 Echocardiogram findings in Takotsubo cardiomyopathy show significant left ventricular (LV) dysfunction or regional dysfunction that is not in one coronary artery distribution.12,13 There will often be apical dilation or ballooning with dyskinesia but more preserved function at the base and normal dimensions.14,15 A negative cardiac catheterization or catheterization in the absence of significant disease is required to confirm the diagnosis.16 The LV function usually returns to baseline in 1 to 4 weeks, but there can be recurrence in some patients.6,17 The condition is also associated with a large burden of morbidity and mortality.6,18 In a case series by Gopalakrishnan et al6 of 56 patients, there was an 8.9% in-hospital mortality rate and an additional 17.9% out-of-hospital mortality rate even in patients in whom LV function had returned to normal.
In a review by Gianni et al,19 4.2% of patients with Takotsubo cardiomyopathy present with or go into cardiogenic shock at some point during admission, and up to 2% of patients who present with acute myocardial infarction have Takotsubo cardiomyopathy. Patients can go into cardiogenic shock due to depressed EF or LV outflow tract obstruction from hyperkinesis of the basilar segments. Some of these patients may be sent directly to the catheter laboratory based on ST elevations on ECG, in which case the diagnosis is made there. Our patient, however, did not have ST elevation and later became unstable on the floor. Citro et al20 suggest that a patient with a predisposition for Takotsubo cardiomyopathy (eg, postmenopausal patients, those who experienced a trigger event), in the right clinical setting and without ST-segment elevation on ECG, could be managed more conservatively with delayed cardiac angiography or CT angiography (CTA) evaluation of the coronary arteries (sparing the patient an invasive procedure)—as long as ultrasound was consistent with typical Takotsubo cardiomyopathy findings. However, CTA is still needed to make the diagnosis.
At this time, Takotsubo cardiomyopathy should remain an important part of the differential diagnosis for emergency patients who have chest pain—especially for postmenopausal women with a history of significant stressor—as early recognition can lead to better patient care.
Conclusion
This case highlights the importance of POC ultrasound in the management of patients in the ED and after admission. The care of our patient was enhanced by the ability to take a real-time look at her EF and cardiac function at the time of admission through bedside ultrasound. This information guided her management and optimized stabilization.