Chief Complaint: Chest pain
1. What are the significant findings in the above ultrasound clips?
2. What is the pathophysiology of this particular entity?
3. What are the potential complications of this entity? Can emergency physicians reliably use Point-of-Care Ultrasound (POCUS) to diagnose and treat these complications early?
A 68 year old female from Guyana with a history of diabetes, hypertension, and cervical cancer presents to the emergency department (ED) with acute onset chest pain that started while at her gynecology clinic receiving her first cycle of chemotherapy. On arrival, she appeared mildly uncomfortable and diaphoretic. Her vital signs were BP 168/85, HR 84, RR 18 and oxygen saturation 95%. The initial 12-lead EKG demonstrated ST-segment elevations in V2-V6, with ST-segment depression in AVR and mild QT prolongation. A STEMI alert was initiated and the patient was given aspirin, Plavix and morphine for pain control. Repeat EKG approximately 10 minutes later demonstrated resolution of the ST-segment elevations. At that time a cardiac POCUS was performed.
Initial troponin I was elevated to 7 ng/mL and the patient was taken emergently for cardiac catheterization. No culprit lesion was identified for revascularization. Formal transthoracic echocardiogram (TTE) was performed which demonstrated an ejection fraction of 25%, akinesis of the mid inferolateral, apical lateral, mid septum, left ventricular (LV) apex, and an aneurysm of the LV apex.
Role of Point-of-Care Echocardiography for Patients with Acute Chest Pain:
TTE POCUS is an integral tool for emergency physicians to diagnose pericardial effusion and tamponade physiology, estimate LV ejection fraction and identify signs of right heart strain. TTE POCUS is particularly valuable when used to evaluate and manage a critically ill patient presenting with chest pain. By evaluating cardiac contractility and wall motion abnormalities, emergency physicians can rapidly correlate EKG abnormalities with signs of potential ongoing ischemia. Bedside ultrasound can also be used to quickly diagnose a low LV ejection fraction and identify pulmonary edema consistent with acute heart failure.1 Obtaining important adjunctive goal-directed information in a short period of time can help diagnose, guide management, and achieve appropriate rapid disposition.
Answers to Questions:
Clip 1 is a parasternal long-axis view of the heart demonstrating apical ballooning and hypokinesis with preservation of cardiac function of the basal segments. Clip 2 is a parasternal short-axis view of the heart that is slightly apical relative to the papillary muscles again demonstrating ballooning and concentric hypokinesis. Takotsubo cardiomyopathy, or “broken-heart syndrome” typically presents with acute onset chest pain, often mimicking acute coronary syndrome. The patient characteristically has LV apical ballooning with preserved function of the base with elevated cardiac biomarkers in the absence of angiographically significant coronary artery stenosis.2
Takotsubo cardiomyopathy is typically precipitated by an acutely physically or emotionally stressful event.3 The pathophysiology behind the entity is unclear; literature has suggested acute coronary vasospasm, microcirculatory dysfunction, excessive catecholamine stimulation or myocardial stunning.4-8 The left ventricular apex is particularly vulnerable as it has limited coronary blood supply and is more sensitive to adrenergic stimulation.2 In 28% of cases, the apical ballooning develops in critically ill patients with no primary heart disease.9 Takotsubo cardiomyopathy is more common in the elderly and postmenopausal females.10
Changes in LV ejection fraction in Takotsubo cardiomyopathy can often appear similar to those seen in ischemic heart disease, and functional valve disturbances can also develop.11 Yet, treatment of ischemic heart disease has not shown to be of any benefit in patients with Takotsubo cardiomyopathy, and may lead to potential adverse effects.12 Collaboration with your cardiology colleagues is imperative in determining the appropriate course of management for your patient when presenting with acute onset chest pain and EKG abnormalities. Some patients, usually those with medical illness as the stressful trigger, require acute hemodynamic support for complications such as pulmonary edema, arrhythmias, conduction abnormalities, thromboembolism and cardiogenic shock.13 TTE POCUS can be useful in the acute setting in identifying pulmonary edema, acute heart strain and changes in ejection fraction, and help guide management. The majority (approximately 96% of patients) have complete short-term resolution of both the apical wall motion abnormality and the depressed LV ejection fraction.14-16 However, recent literature has suggested that long-term prognostic consequences of Takotsubo cardiomyopathy remain unknown. Mortality rates range from 5-17%, with increased long-term mortality in patients with risk factors including male sex, diabetes, and Killip class 3/4 (acute myocardial infarction with pulmonary edema).17
Takotsubo cardiomyopathy is an increasingly recognized and reported syndrome. There is a high incidence of complications during the acute phase and current guidelines for clinical management are limited. Early identification in the ED using ultrasound can help guide management.