Direct current shock therapy of cardiac arrhythmias.

Abstract

The results of direct current shock therapy of 200 episodes of cardiac arrhythmia are reported. Such treatment was given in 170 episodes of atrial fibrillation, 15 of atrial flutter, 9 of atrial tachycardia, 4 episodes of ventricular tachycardia, and 2 of ventricular fibrillation. In atrial fibrillation, sinus rhythm was restored in 87% of the cases. The recurrence rate over a follow-up period of up to 15 mo. was 60%, in spite of drug prophylaxis. Direct current shock therapy was successful in all cases of atrial tachycardia and atrial flutter, and in 3 out of 4 cases of ventricular tachycardia. One episode of systemic embolism followed the conversion of atrial fibrillation to sinus rhythm in a patient not receiving anticoagulants, but the place of anticoagulant prophylaxis in relation to cardioversion has yet to be clarified. Transient S-T segment elevation occurred in 5 patients after direct current shock therapy, and gross T wave inversion considered to be due to cardiac infarction in 2.