Complications in 220 patients with cardiac dysrhythmias treated by phased direct current shock, and indications for electroconversion.

Abstract

Of 220 consecutive patients with atrial dysrhythmias and ventricular tachycardia treated by phased direct current shock .14.5% developed complications. Increases in the serum levels of glutamic oxa-loacetic transaminase and lactic dehydrogenase occurred in 20 of the 220 patients, episodes of pulmonary edema in 2, enlargement of the heart and pulmonary venous congestion in 7, ecg changes in 6, andpulmonary or systemic emboli in 3. Death was directly or indirectly related to direct current shock in 4 patients. Complications were related to higher energy level settings especially those exceeding 300 joules. Patients most likely to develop complications were those with dysrhythmias in association with ischemic heart disease and cardiomyopathy, and when atrial fibrillation of whatever cause was present for more than 3 years. Patients with lone atrial fibrillation and flutter also had a high incidence of complications. Indications for phased direct current in the management of cardiac dysrhythmias were reviewed, and conclusions drawn regarding energy level settings to be used. Attempts should seldom be made to convert lone atrial fibrillation and flutter by direct current shock. Important electrical variables in the apparatus for phased direct current shock were reviewed.