Pathophysiology of the Syndrome: Biventricular Takotsubo Cardiomyopathy: Case Study and Review of Literature

Biventricular takotsubo cardiomyopathy is associated with more hemodynamic instability than is isolated left ventricular takotsubo cardiomyopathy; medical management is more invasive and the course of hospitalization is longer.In March 2011, a 62-year-old woman presented at our emergency department with abdominal pain, nausea, and vomiting. On hospital day 2, she experienced chest pain. An electrocardiogram and cardiac enzyme levels suggested an acute myocardial infarction. She underwent cardiac angiography and was found to have severe left ventricular systolic dysfunction involving the mid and apical segments, which resulted in a left ventricular ejection fraction of 0.10 to 0.15 in the absence of obstructive coronary artery disease. Her hospital course was complicated by cardiogenic shock that required hemodynamic support with an intra-aortic balloon pump and dobutamine. A transthoracic echocardiogram revealed akinesis of the mid-to-distal segments of the left ventricle and mid-to-apical dyskinesis of the right ventricular free wall characteristic of biventricular takotsubo cardiomyopathy. After several days of medical management, the patient was discharged from the hospital in stable condition.To the best of our knowledge, this is the first review of the literature on biventricular takotsubo cardiomyopathy that compares its hemodynamic instability and medical management requirements with those of isolated left ventricular takotsubo cardiomyopathy. Herein, we discuss the case of our patient, review the pertinent medical literature, and convey the prevalence and importance of right ventricular involvement in patients with takotsubo cardiomyopathy.Key words: Cardiomyopathies/radiography, hemodynamic instability/takotsubo, magnetic resonance angiography, takotsubo cardiomyopathy, biventricular/diagnosis, transient apical ballooning syndrome, ventricular dysfunction, left, ventricular dysfunction, rightTransient left ventricular apical ballooning syndrome (TLVABS) is an acute cardiac syndrome that typically is characterized by transient left ventricular (LV) wall-motion abnormalities, electrocardiographic (ECG) findings of ST-T segment changes, and minimal release of cardiac enzymes in the absence of significant stenosis of the coronary arteries (<50% luminal stenosis).^1–8 This syndrome was first described in Japan in 1991 and named takotsubo-like LV dysfunction in reference to the asynergy, which consists of hypokinesis or akinesis of the mid-to-apical LV and hyperkinesis of the basal LV extending over more than one coronary artery region.^8–11 Since then, this asynergy has been called takotsubo cardiomyopathy (TC), stress cardiomyopathy, ampulla syndrome, broken-heart syndrome, and neurogenic stunned myocardium.^12–14 Takotsubo cardiomyopathy presents clinically with chest pain and dyspnea associated with ECG changes, thereby mimicking ST-segment elevation myocardial infarction that is often preceded by emotional or physical stress.^1-7,9,10 Indeed ST-segment elevation is the most common ECG abnormality, reported in approximately 82% of patients with TC, followed by T-wave inversion in 64%.^8,15 This peculiar cardiac syndrome results in severe impairment of systolic function.There are several variants of TC. Isolated LV involvement is the most common variant, but right ventricular (RV) involvement is gaining increased recognition. Although there is only one documented case of isolated RV stress cardiomyopathy,¹⁶ the recognition of biventricular TC is increasing. It has been reported that RV involvement affects approximately 25% to 42% of patients diagnosed with TC.^12,13,17,18 In addition to isolated LV, isolated RV, and biventricular involvement, a variety of ballooning patterns has been observed. The typical apical-ballooning shape, with akinesis of the apical and mid-ventricular LV segments, is the most common; however, a mid-ventricular variant with apical sparing and a variant with isolated basal ballooning have been recognized.¹⁸ Left ventricular systolic dysfunction and heart failure—with simultaneous RV dysfunction—identifies a patient population with an extremely poor prognosis.¹⁹ Therefore, it is not surprising that TC with RV involvement appears to be associated with more severe LV dysfunction that results in significantly longer hospitalization and hemodynamic instability that is associated with a worse prognosis.^1-4,13,18 Clinicians need to be aware of the prevalence and complications of RV involvement and dysfunction, because it can affect patient management, morbidity, and, ultimately, mortality rates in substantial ways.The data concerning RV involvement in TC are sparse, because they are derived from several case reports and case series studies. This review of the literature documents the prevalence, pathophysiology, diagnostic imaging characteristics, clinical findings, management, and prognosis of patients with biventricular TC. Throughout this article, TC with RV involvement will be referred to as biventricular TC, whereas classic left ventricular TC (with apical ballooning) will be referred to as TLVABS. All of the documented cases of biventricular TC have been evaluated and analyzed in regard to how the patient presented, how the TC was diagnosed and managed, and how we can improve in managing the even more hemodynamically unstable biventricular TC, in comparison with TLVABS.