Neurogenic Stunned Myocardium: A Literature Review

Abstract

Neurogenic stunned myocardium (NSM) is defined as the occurrence of cardiac abnormalities due to neurological events such as stroke, seizures, etc. These events lead to dysfunction of the autonomic nervous system (ANS) and ultimately cause injury to the myocardium. The clinical features seen in NSM include elevated troponin level, left ventricular dysfunction, and changes on the electrocardiogram (ECG). However, these features are also seen in Takotsubo cardiomyopathy as well as in an acute coronary syndrome (ACS). Hence, diagnosing the condition by clinical presentation alone is difficult. Thus, a patient of NSM who is at increased risk of developing coronary heart disease may require invasive procedures such as cardiac catheterization to rule out ACS. This review aims at raising awareness about NSM among physicians so that management of patients can be individualized.

“Broken Heart” and “Broken Brain”: Which Connection?

“…Pathological responses in the CNS can elicit, mainly through these mechanisms, abnormal effects in heart function, such as alteration of blood pressure and cardiac rhythm, alteration in the conduction of the electric impulses and (mainly transient) cardiomyopathies. Although a univocal classification of these cardiomyopathies is still not available, two main entities have been described: the neurologic stunned myocardium (NSM) [ 13 ] and the TTC [ 4 , 14 ]. In both, the pathophysiological mechanism resides probably in a catecholamine storm, triggered by an acute neurological injury in NSM (mainly in the caudal ventrolateral medulla, the tractus solitarius, the dorsal motor vagal nucleus and the posterior hypothalamus), by emotional or physical stress with consequent activation of hypotalamo-pituitary-adrenal and sympatho-adrenomedullary axis in TTC.…”

Ischaemic stroke-induced distal organ damage: pathophysiology and new therapeutic strategies

“…A meta-analysis including 67,000 patients demonstrated that the annual risk for developing myocardial infarction after stroke is about 2%, followed by a 20% 10-year risk of myocardial ischaemia [60,62]. A common myocardial infarction-like manifestation is neurogenic stunned myocardium, which differs from traditional myocardial damage because of the absence of coronary artery occlusion [63].…”

Pulmonary Edema and Stunned Myocardium in Subarachnoid Hemorrhage

“…A stunned myocardium is defined as a state in which a given section of the myocardium manifests with a certain form of contractile abnormality. Similarly, a neurogenic stunned myocardium refers to cardiac abnormalities that occur as a result of neurological disorders, such as seizures, stroke, etc [11]. A neurogenic stunned myocardium occurs secondary to reversible posterior leukoencephalopathy, seizures, subarachnoid bleed, Guillain-Barre syndrome, stroke, and/or brain tumor [12].…”

“…These events result in autonomic nervous system dysfunction and cause myocardial injury. Clinical features associated with neurogenic stunned myocardium include left ventricular dysfunction, elevated troponin level, and changes on the electrocardiogram [11]. Stunned myocardium is characterized by reversible left ventricular dysfunction and may be caused by a subarachnoid hemorrhage.…”