The Superfast Atrial Recharge Pulse: A Cause of Pectoral Muscle Stimulation in Patients Equipped with a Unipolar DDD Pacemaker

Abstract

Pectoral muscle stimulation may cause serious discomfort to patients equipped with a pulse generator. Insulation defects of the lead, connector problems and defective coating of the pacemaker can are common causes of local muscle contractions. This report describes pectoral muscle stimulation caused by the atrial superfast recharge pulse incorporated into the atrial channel of a commercially available unipolar DDD pacemaker. As pectoral muscle stimulation could not be eliminated by reprogramming the pacemaker to a lower atrial output in some patients a redesign of the pacemaker is highly required.

A video demonstration of pacemaker-induced pectoral muscle stimulation

“…Common causes of local muscle contractions are insulation defect of the lead, positioning of the anode directly on the muscle, defective coating of the pacemaker can or connector problems 1 2. In this case, lead insulation defect was suspected due to reduced pacing impedance.…”