912-39 Interactions Between Handy Phones and Pacemaker Function in Patients with Permanent Pacemakers

Abstract

To date, it is unclear whether handy phones (C-net or D-net) can be used safely by patients with permanent pacemakers. Possible interactions between handy phones and pacemaker function include: 1) inhibition of the pacemaker, 2) change of temporary or permanent pacemaker programming, and 3) switch to VOO mode. Thirty pts (14 f, age: 48–87 years) with single chamber (13 pts) or dual chamber pacemakers (17 pts) were studied during routine follow-up in our outpatient department. Pacemaker sensing was unipolar in 17 pts, and bipolar in 13 pts. After completion of the routine pacemaker check, each pt was asked to make several phone calls with a handy phone (Ericsson R ; D-net; 2.5 watts). A surface ECG (Mingograph) was recorded continuously during each phone call in order to detect possible interactions between pacemaker function and handy phone use. Phone calls were repeated after pacemaker programming to 1) minimum ventricular rate of 90 bpm and previous sensitivity, and 2) minimum rate of 90 bpm and maximum sensitivity without T-wave oversensing. A change of the pacemaker programming or a switch to VOO pacing due to handy phone calls was not observed in any pt. Two of 30 pts (3%) reproducibly showed intermittent pacemaker inhibition during handy phone calls. Both pacemakers had unipolar sensing. Both pts remained asymptomatic during pacemaker inhibition since they were not completely pacemaker dependent. Although interactions between handy phone use and pacemaker function appear to be rare, pacemaker inhibition during phone calls may occasionaly occur, particularly if unipolar sensing is used. Therefore, pacemaker dependent patients should currently avoid the use of handy phones.