Electrocardiographic Changes in Central Nervous System Disease

Neurocardiogenic injury in neurovascular disorders

cardiac injury occurs frequently after stroke; and the most widely investigated form of neurocardiogenic injury is aneurysmal subarachnoid hemorrhage. Echocardiography and screening for elevated troponin and B-type natriuretic peptide levels may help prognosticate and guide treatment of stroke. Cardiac catheterization is not routinely recommended in subarachnoid hemorrhage patients with left ventricular dysfunction and elevated troponin. The priority should be treatment of the underlying neurologic condition, even in patients with left ventricular dysfunction. Cardiac injury that occurs after subarachnoid hemorrhage appears to be reversible. In contrast to subarachnoid hemorrhage patients, patients with ischemic stroke are more likely to have concomitant significant heart disease. For patients who develop brain death, cardiac evaluation under optimal conditions may help increase the organ donor pool.

The Clinical Value of the ECG in Noncardiac Conditions

The ECG is an indispensable tool in the ICU for the detection and diagnosis of heart disease. ECG abnormalities however can be present in a wide variety of noncardiac conditions, complicating the differential diagnosis with primary cardiac pathology. This overview discusses the ECG abnormalities and their pathophysiologic basis in the most frequently encountered noncardiac conditions, such as electrolyte abnormalities, pulmonary embolism, CNS diseases, esophageal disorders, hypothermia, and drug-related and other conditions. Knowledge of the characteristic ECG changes may provide early clues to the presence of these disorders, the prompt recognition of which can be life saving.

Clinical evaluation of patients with head trauma

Head trauma is a very common and sometimes life-threatening medical condition that involves sports medicine physicians, emergency room physicians, neurologists, neurosurgeons, orthopedists, anesthesiologists, rehabilitation physicians, psychiatrists, and radiologists; as well as allied health care workers such as physical, occupational, and speech therapists, clinical psychologists, neuropsychologists, and many others. Head trauma needs to be approached by a mutlidisciplinary team because it is complex. Specialized trauma centers incorporate all of these specialists and the best medical technology for optimal management of head trauma. The following chapters cover the use of different neuroimaging techniques, including CT scan and MRI, that greatly aid clinicians in evaluation and management of head trauma patients. These advances have truly revolutionized medicine and it has happened rapidly--pneumoencephalography was the neuroimaging study of choice less than half a century ago. The future of neuroimaging in head trauma will undoubtedly include advances we can not yet foresee but that will allow clinicians to continue to improve patient care.

The mind-heart connection in coronary artery disease

Mind and heart are connected by neurocardiologic pathways. Psychosocial risk factors produce sympathetic activation, resulting in mortality in coronary artery disease. Aspirin, exercise, and psychosocial and spiritual supports are important resources in protecting the heart against these risk factors.

Asymptomatic temporary atrioventricular dissociation complicating meningococcal meningitis

We present a case of a young man with meningococcal meningitis and various asymptomatic temporary ECG abnormalities, including sinus bradycardia, atrioventricular dissociation and non specific ST-T changes.

Electrocardiographic markers of abnormal left ventricular wall motion in acute subarachnoid hemorrhage

A reversible and presumably neurogenic form of myocardial dysfunction may occur following subarachnoid hemorrhage (SAH), but the relationship of this finding to electrocardiographic abnormalities remains unclear. To clarify this issue, serial electrocardiograms (ECGs, mean 6.2 per patient) and echocardiograms (mean 3.4 days after SAH) were obtained in 57 SAH patients without preexisting cardiac disease. The goal was to determine which specific electrocardiographic changes, if any, reflect abnormal left ventricular wall motion in acute SAH. Wall motion abnormalities were identified in five (8%) of 57 patients. Four of these affected patients experienced hypotension (systolic blood pressure < 100 mm Hg) and three exhibited pulmonary edema within 6 hours of SAH, compared to none of the 52 patients with normal wall motion (p < 0.0001). Patients with abnormal wall motion were more likely than patients with normal echocardiograms to have symmetrical T wave inversion (five of five vs. seven of 52, p < 0.001) and severe (> or = 500 msec) QTc segment prolongation (five of five vs. three of 52, p < 0.001) on serial ECGs. These associations maintained their significance with analysis limited to single ECGs performed on or near the day of echocardiography. Abnormal wall motion was also associated with borderline (2% to 5%) creatine kinase MB elevation (five of five vs. three of 52, p < 0.001) and poor neurological grade (p < 0.0001). Although no combination of findings on a single ECG resulted in 100% sensitivity for abnormal wall motion, the presence of either inverted T waves or severe QTc segment prolongation on serial ECGs was associated with 100% sensitivity and 81% specificity. These results demonstrate an association between reduced left ventricular systolic function, mild creatine kinase MB elevation, and electrocardiographic repolarization abnormalities in acute SAH. Symmetrical T wave inversion and severe QTc segment prolongation best identified patients at risk for myocardial dysfunction and may serve as useful criteria for echocardiographic screening following SAH.