In view of the extensive wall motion abnormalities, modest rise in cardiac enzymes and mildly abnormal EKG the diagnosis of stress-induced cardiomyopathy was entertained.
Stress cardiomyopathy, also referred to as Takotsubo cardiomyopathy, transient apical ballooning or broken heart syndrome, is a disorder associated with transient left ventricular dysfunction. First described by Dote et al., who named it takotsubo because the shape of the left ventricle resembles a Japanese octopus trap.
Symptoms include acute chest pain and dyspnea accompanied by electrocardiographic changes, absence of substantial coronary artery obstruction.such as ST‐segment elevation and T‐wave inversions, minimal elevation of cardiac enzyme levels and transient wall‐motion abnormalities which usually are not confined to a single coronary artery territory. Complete recovery of contractile function has been documented in nearly all cases over a period of days to weeks but the mechanisms of disease remain unclear.
The prevalence of stress cardiomyopathy among patients with symptoms suggestive of myocardial infarction is 0.7–2.5%, and it is found predominantly in postmenopausal women (90%). The prognosis of stress cardiomyopathy is favorable, although fatal complications, such as cardiogenic shock, malignant arrhythmias and free wall rupture of the left ventricle have been reported. The in-hospital disease-related mortality rate is about 2%.
No large studies have confirmed the etiology of stress cardiomyopathy, so determining the underlying cause has so far not been possible. Several pathological mechanisms have been proposed including:
· Coronary artery vasospasm
· Coronary microcirculation dysfunction
· Obstruction of the left ventricular outflow tract
· Catecholamine overload. Published data suggest that substantially elevated plasma catecholamine levels seen in stress cardiomyopathy patients could be particularly relevant, and result in catecholamine-related toxic effects.
There are no specific treatments for the left ventricular failure characterizing Takotsubo cardiomyopathy because cardiac function is normalized within a few weeks. When shock occurs, intraaortic balloon pumping is established as additional support for the circulation. The administration of cardiotonic agents is not appropriate because of the likelihood of exacerbating the condition. Similarly adrenoceptor blockers, which leave unopposed the potentially adverse effects of high local concentrations of catecholamines at adrenoceptors are better avoided. Given the findings in the animal model, treatment with a combined blocker seems rational, whereas treatment with a catecholamine as a cardiotonic seems contraindicated.
References and further reading:
Takotsubo Cardiomyopathy : A New Form of Acute, Reversible Heart Failure: Yoshihiro J. Akashi, David S. Goldstein, Giuseppe Barbaro and Takashi Ueyama
Mechanisms of stress (Takotsubo) cardiomyopathy : :Holger M. Nef, Helge Möllmann, Yoshihiro J. Akashi and Christian W. Hamm
Nat. Rev. Cardiol. 7, 187–193 (2010)
Case compiled with the help of Wissam Alajaji M.D., second year cardiology fellow AUBMC.