[Effect of elevated plasma norepinephrine on electrocardiographic changes in subarachnoid hemorrhage]

We compared electrocardiographic abnormalities and plasma norepinephrine concentration in 40 patients with subarachnoid hemorrhage within the first 24 hours, at 72 hours, and after 1 week. In the 20 patients with high plasma norepinephrine concentrations within the first 24 hours, sinus tachycardia and negative T waves were more frequently seen than in the 20 patients with normal plasma norepinephrine concentrations. After 72 hours, only sinus tachycardia was found with increased frequency in the 26 patients with high plasma norepinephrine concentrations. Although 24 patients had high plasma norepinephrine concentrations after 1 week, we found no difference in the frequency of electrocardiographic abnormalities as compared with patients with normal plasma norepinephrine. QT prolongation, U waves, ST depression, and arrhythmias were found with similar frequency in patients with high and normal plasma norepinephrine concentrations. We conclude that, with the exception of sinus tachycardia and negative T waves, other electrocardiographic changes in patients with subarachnoid hemorrhage do not depend on elevated plasma norepinephrine concentrations.