The effect of ergotamine tartrate on the abnormal electrocardiogram in patients previously prepared with tetraethylammonium chloride

Abstract

The changes in the T waves which may occur with a change in posture, have been thought by some authors to be due to a change in sympathetic tone. Nordenfeldt, 7 in a series of experiments, demonstrated that the injection of ergotamine tartrate would prevent the recurrence of posturally inverted T waves in patients who previously had shown such changes with the assumption of the erect posture. Wendkos 11 stated that inverted T waves which may occur in the emotionally tense person or the neurocirculatory asthenic may be prevented or normalized by the use of a sympathicolytic drug. He also concluded that excessive sympathetic tone was responsible for the inverted T waves and that, with the use of ergotamine tartrate, a differentiation between functionally inverted and organically inverted T waves could be made. In a previous series of experiments 9 it was found that the positional inversion of previously upright T waves was not always prevented with the use of ergotamine tartrate and it was demonstrated also that normalization of inverted T waves due to organic heart disease could be induced by the administration of ergotamine preparations. 10 Because these results were not consistent with those of the previous investigators, it was thought that the normalization of inverted T waves by ergotamine was not due to changes in sympathetic tone. The appearance of anginal pain after the injection of ergotamine preparations and the normalizing of organically inverted T waves suggested a direct action of these preparations either on the coronary arteries or on the heart muscle. The development and clinical application of tetraethylammonium chloride introduced a means of blocking the transmission of impulses across the autonomic ganglia so that the direct action of ergotamine tartrate on the heart muscle or coronary arteries could be studied. During these experiments, some coincidental observations were made on the effect of tetraethylammonium chloride on the blood pressure and on the electrocardiogram.