Possible role of catecholamines, corticosteroids, and potassium in production of electrocardiographic abnormalities associated with subarachnoid haemorrhage.

Abstract

In a study of 40 patients with subarachnoid haemorrhage, of whom 24 were women of mean age 42 and i6 men of mean age 4i, an attempt has been made to correlate electrocardiographic abnormalities with urinary normetanephrins and metanephrins, plasma cortisol, and with serum and total body potassium levels. Urinary normetanephrins and metanephrins, and plasma cortisol values were significantly raised in I9 patients with abnormal electrocardiograms compared with the 8 patients with normal cardiograms. In the former group urinary catecholamine and plasma cortisol concentrations remained at abnormally high levels throughout a 2- week observation period. Electrocardiographic features which showed a strong correlation with high urinary normetanephrin levels were a short PR interval and peaking of the T waves, and with high urinary metane- phrin levels peaking of the P waves. Weaker, though significant, relations with high urinary catecholamines were shown by T wave inversion, long QTc, tall U waves, and Q waves. High plasma cortisol levels were significantly related to peaking of the P waves, a short PR interval, and peaking of the T waves. No significant differences in serum potassium levels in patients with either normal or abnormal electrocardiograms were revealed. Thirteen cases had total body exchangeable potassium measured about one week after subarachnoid haemorrhage, and abnormally low or low normal levels were observed in 9 of the IO patients with abnormal or changing electrocardiograms. A second estimation of total body potassium in 6 cases, several months after the subarachnoid haemorrhage, showed higher values in 5 cases with one low normal remaining unchanged. No second estimation fell outside the normal range.