Use of a transurethral microwave thermotherapeutic device with permanent pacemakers and implantable defibrillators

Objective: To determine whether a device (Urologix Targis system) used for transurethral microwave treatment interferes with sensing, pacing, and arrh ythmia detection by permanent pacemakers and implantable cardioverter-defib rillators (ICDs). Methods: We tested 13 pacemakers in both bipolar and unipolar sensing confi gurations and 8 ICDs in vitro, Pacemakers and ICDs were programmed to their most sensitive settings. Energy outputs of the microwave device were typic al of those used clinically. The probe of the microwave device was anchored 1.2 cm from the pacemaker or ICD being tested. Results: No sensing, pacing, or arrhythmic interactions were noted with any ICD or any pacemaker programmed to the bipolar configuration, One pacemake r (Guidant Vigor 1230) showed intermittent tracking when programmed to the unipolar configuration. Conclusions: Most patients with permanent pacemakers or ICDs can safely und ergo transurethral microwave therapy using the device tested. Pacemakers an d ICDs should be programmed to the bipolar configuration (if available) dur ing therapy, The pacemaker or ICD should be interrogated before and after t herapy to determine whether programming changes occurred as a result of tre atment. However, our findings suggest that this is unlikely.