The CLEAR Multicenter Study Concept: Comparing Closed Loop Stimulation and Accelerometer Rate-Adaptive Pacing

Summary The Inos 2+ CLS cardiac pacemaker is a rate-adaptive, dual-chamber device that incorporates the Closed Loop Stimulation (CLS) principle. It continuously monitors the heart's contraction dynamics through unipolar intracardiac impedance. The CLS system is expected to be superior to the accelerometer sensors that regulate the pacing rate during physical stress based on body movement and acceleration. The planned CLEAR multicenter study plans to compare the rate adaption in Inos 2+ CLS and Philos DR (accelerometer) pacemakers during a treadmill test, daily activities, and a range of control tests. The objective is to assess the function of the autonomic nervous system and of the cardiovascular control loop. Our study hypothesis is that the CLS system will adequately react during all tests and will not be inferior to the accelerometer sensor. A total of 60 patients will be randomized for Inos 2+ CLS or Philos DR pacemaker implantation. During the first 6 postoperative weeks, the tests will be carried out in the DDD mode to document the patients' restricted performance capability and chronotropic incompetence. Thereafter, all the tests will be repeated in the respective rate-adaptive mode, and the results of CLS and accelerometer rateadaptive pacing will be compared.