Background: The objectives of this study were to compare pacing rate adaptation based on closed loop stimulation (CLS) and accelerometer sensor (ACS) and to assess the basic pacing configuration during stairway walking.
Methods: Four days after Protos (Biotronik, Germany) pacemaker (PM) implantation, 36 chronotropically incompetent patients were divided into the ACS-based (DDDR) or CLS-based (DDD-CLS) rate adaptive mode. At the 1-month follow-up, the sensors were crossed over. Stairway walking, represented by static movement, was performed in the ACS and CLS rate-adaptive modes, respectively. PM interrogation was performed to access pacing configuration after each of stairway walking. At the end of study, patients had to select the individually preferred sensor.
Results: Heart rate (HR) during stairway walking was more increased in the CLS mode than in the ACS mode (5.7 짹 8.6 beats per minute (bpm) vs. 3.8 짹 6.9 bpm, P=0.016). At the end of the walk, HR was higher by 7.1 짹 10.9 bpm in ACS mode than in CLS mode (P=0.041). When the two pacing modes were compared on the basis of information from pacemaker interrogation, atrial pacing was 55.9% in CLS mode with respect to 17.6% of ACS mode (P=0.003). Almost twice as many patients preferred CLS over ACS (47% vs. 22%, P=0.002).
Conclusion: CLS-based rate adaptive mode is more helpful to make high rate response in static movement and provides more physiologic pacing configuration for chronotropically incompetent patients.
Keywords: closed loop stimulation, accelerometer, pacing, chronotropic incompetence