Ventricular Fibrillation and Competitive Pacing

Abstract

SUDDEN death in persons with artificial pacemakers is a continuing and disturbing problem. Causes include pacemaker-catheter displacement, electric-component failure, broken wires and rising pacing threshold. Each of these may be resolved in a relatively simple fashion once recognized.^{1 , 2} More of an unsolved problem is that of competitive rhythm between pacemaker-induced impulses and the patient's own intrinsic focus or foci. Sowton,³ comparing mortality rates between patients with competitive and noncompetitive rhythms, found the rate five times higher in the former. Individual case reports^{4 , 5} have documented the onset of ventricular fibrillation or tachycardia, or both, at the moment of inscription of the . . .