Electrocardiographic changes following electroconvulsive therapy.

This paper reports a study of the effects of ECT (electroconvulsive therapy) upon cardiac function (as judged by electrocardiographic changes) in 24 patients who were given 139 treatments in all. Of the 24 patients 13 were studied over a 24-h period using monitoring equipment. No potentially dangerous arrhythmias were encountered. Modified ECT was found to give rise to sinus tachycardia, which was considerably more prolonged than previously reported. The tachycardia was shown in some cases to be accompanied by a depression of the ST segment and may hence be potentially harmful to those with pre-existing ischaemic heart disease. In such patients consideration should be given to the prior administration of beta-adrenergic blocking drugs and/or oxygen.