Follow-up of an activity-sensing, rate-modulated pacing device, including transtelephonic exercise assessment

Single-chamber rate-modulated (ventricular or atrial demand [VVIR or AAIR]) pacemakers are now an accepted and frequently used pacing modality. Although several sensor-driven pacemakers are currently under investigation, activity-sensing pacemakers have been used most frequently to date. We assessed our implantation and follow-up experience with 156 activity-sensing pacemakers. Analysis of the patient population revealed an age range of 6 to 91 years and a variety of indications for pacing, the most common being atrioventricular block. Specific programming techniques were adopted for assessing these pacemakers. Although several episodes of reprogramming may be necessary to identify the optimal sensor settings for an individual patient, once optimal programming has been achieved, the sensing characteristics seem to have long-term stability. An important part of our follow-up procedure involves transtelephonic exercise, which allows some degree of long-term assessment of the sensor. All but six patients with pacemakers programmed to the sensor-driven mode (VVIR or AAIR) had evidence of sensor-driven pacing during transtelephonic exercise. Thus, this adjunct seems helpful for follow-up of some rate-modulated pacemakers.