On presentation, our patient had several possible causes for his syncopal episode: an abnormal ECG (CV); multiple episodes of emesis (volume depletion); and headache (cerebrovascular). The EP worked up all three of these signs and symptoms simultaneously as is the appropriate protocol when evaluating an ED patient presenting with undifferentiated syncope.
Signs and Symptoms
Patients with undiagnosed brain tumors normally present with headache, seizures, nausea, vomiting, focal neurological deficits, or an altered mental status.3 Syncope is a very rare manifestation of a brain tumor3; however, our patient did complain of headache, nausea, and vomiting.
In addition to the unusual cause of the syncope, the abnormally large upright T waves make this case even more notable. T-wave changes are the most common ECG abnormality, seen in about 50% of abnormal tracings reviewed in a hospital population and in 2.4% of all ECGs.4
In general, T-wave changes are a result of local changes in the duration of repolarization. T-wave inversion is the most common T-wave abnormality and is typically observed in the setting of ischemia, post-ingestion of food, following an episode of tachycardia or anxiety, and autonomic dysfunction.5 However, in patients who have a cerebral etiology (usually hemorrhage), the T-wave changes may be either upright (as in our case) or inverted.5 Historically, subarachnoid hemorrhage (SAH) has been associated with ST-segment elevation and T-wave inversion. Hypothalamic stimulation and autonomic dysfunction have been linked to abnormal T-waves, but this has not been conclusively proven to be the cause of the abnormality.6 For all of the aforementioned reasons, the specificity for a given cause of T-wave changes is exceedingly low.5
Hyperacute T-wave amplitude, with prominent symmetrical T waves in at least two continuous leads, may be the earliest sign of acute transmural myocardial infarction (MI).7 It usually persists for only a brief time before other ECG findings of acute MI are observed. Other common causes of hyperacute T waves include hyperkalemia (usually narrow-based, and peaked), early repolarization, left ventricular hypertrophy, and acute myocarditis.8 Less common causes of prominent T waves include pre-excitation syndromes, pericarditis, and scorpion stings.9,10
Summary
It is unclear why our patient, who had a hemangioblastoma, demonstrated hyperacute T-wave abnormality on ECG. The abnormal upright T waves may have occurred secondary to the same theories regarding SAH, hypothalamic stimulation, or autonomic dysfunction. Regardless of the underlying etiology, this case serves as a reminder to the EP that not all T-wave changes on ECG are cardiac in origin.