Correspondence

Neurocardiology refers to the interplay between the nervous system and the cardiovascular system. Stress-related cardiomyopathy exemplifies the brain–heart connection and occurs in several conditions with acute brain injury that share oversympathetic activation. The brain's influences on the heart can include elevated cardiac markers, arrhythmias, repolarization abnormalities on electrocardiogram, myocardial necrosis, and autonomic dysfunction. The neurogenic stunned myocardium in aneurysmal subarachnoid hemorrhage represents one end of the spectrum, and is associated with an explosive rise in intracranial pressure that results in excess catecholamine state and possibly CBN. A brain–heart link is more known to cardiologists than neurologists. This chapter provides some insight into the pathophysiology of these pathologic neurocardiac states and their most appropriate management relevant to neurologists.

Cardiac complications are frequently encountered by neurointensivists caring for patients with SAH. Our aim was to better characterize the natural history of various cardiac abnormalities in this population. We sought to determine the risk factors for cardiac abnormalities, patient outcome, and impact of treatment type on cardiac abnormalities.

We performed a single center retrospective review of admissions of patients with aneurysmal SAH to the neurosurgical ICU in a large university hospital. Patient demographics, pertinent history, cardiac tests, hospital LOS, intervention type, and discharge outcome were collected.

Data from 266 patients were available for analysis. Of these patients, 50% (n = 133) demonstrated cardiac abnormalities as indicated by abnormal EKG, ECHO, or troponin I. Only age was determined to be an independent statistically significant predictor of cardiac abnormality (P = .01). There was no difference in mortality between the cardiac abnormality and control groups (P = .33). However, there was increased morbidity in the cardiac abnormality group as demonstrated by worse discharge disposition, in addition to increased length of hospital stay (22.6 vs 17.1 days, P < .01). The incidence of cardiac abnormalities was the same among surgical and endovascular treatment groups.

Cardiac abnormalities, including those that meet ACC criteria for MI, are common among patients with SAH. However, in contrast to cardiac events outside the context of SAH, these abnormalities do not increase mortality. They do, however, adversely affect discharge disposition and prolong hospital LOS. The type of aneurysm treatment does not affect the incidence or outcome of cardiac abnormalities.

Neurogenic stunned myocardium has been described in association with subarachnoid hemorrhage, Guillain–Barre syndrome, and metastatic brain tumors. We describe a case of neurogenic stunned myocardium associated with acute myelitis. A 27-year-old female presented with acute onset of quadriplegia, sensory deficit, and acute pulmonary edema. Magnetic resonance imaging was consistent with acute myelitis. Echocardiogram showed left ventricular ejection fraction of 35% with moderate to severe global hypokinesis. During the course of admission, she had several episodes of sinus bradycardia and high degree atrioventricular block. All cardiac abnormalities resolved completely in eight days of admission.

Cardiac alterations associated with subarachnoid hemorrhage (SAH) have been recognized and frequently reported. We systematically reviewed the literature on MEDLINE using the key words: SAH + (heart, cardiac, electrocardiogram, cardiac enzymes, troponin, myoglobin, echocardiography, scintigraphy, Holter, and regional wall motion abnormalities) and included all articles describing cardiac abnormalities in the course of SAH whether spontaneous or secondary. The diagnosis of SAH was established by computed tomography scan, lumbar puncture, or brain autopsy. Cardiac abnormalities were identified by electrocardiogram, enzymatic elevation, Holter monitoring, echocardiography, cardiac scintigraphy, coronary angiography, or autopsy. Despite the considerable literature describing cardiac alterations during the course of SAH, epidemiological, pathophysiological, and prognostic aspects are yet to be clarified. Further studies are needed to evaluate the magnitude of this problem. Copyright 2002, Elsevier Science (USA). All rights reserved.