Cardiac stimulation caused by biogalvanic current during pacemaker implantation.

After lead positioning during implantation of a biventricular pacing system intermittent ventricular simulation was observed. There was no pacemaker connected to any of the leads, but ventricular capture could be provoked by an intermittent contact between the lead stylet, which was still partially inserted, and a self-retaining retractor. The same phenomenon was observed from the atrial lead.