Cardiac pacemaker inhibition by transcutaneous electrical nerve stimulation.

The use of transcutaneous electrical nerve stimulation (TENS) has increased in recent years for the management of chronic pain. One of its few contraindications is the presence of a cardiac pacemaker. Clinicians have recommended that cardiac monitoring be performed for a short interrupted period during the first application of TENS to ensure safety. We present two patients who were given trials of TENS for different chronic pain complaints. In both cases, electrocardiograms during the TENS trial did not reveal cardiac pacemaker dysfunction, but extended cardiac monitoring with the Holter monitor showed interference with pacemaker function. The abnormalities did not recur after reprogramming the sensitivity of the pacemakers. We suggest the use of extended cardiac monitoring for patients with cardiac pacemakers during the prolonged use of TENS to ensure safety and to determine any need for reprogramming of the pacemakers. Patients with cardiac pacemakers should not be excluded from the use of TENS, but careful evaluation and extended cardiac monitoring should be performed.