Physiological pacing reduced cardiovascular death and total mortality compared with ventricular pacing only in pacemaker-dependent patients with an unpaced heart rate ≤60 bpm.
RCT (n=2,244)
Does physiological pacing reduce cardiovascular death or stroke in pacemaker-dependent patients compared to ventricular pacing?
Physiological pacing provides a cardiovascular benefit over ventricular pacing specifically in pacemaker-dependent patients with a low unpaced heart rate (≤60 bpm).
BACKGROUND: A recently completed trial, the Canadian Trial of Physiological Pacing (CTOPP), showed that physiological pacing did not significantly reduce mortality, stroke, or heart failure hospitalization, but it did show that atrial fibrillation occurred less frequently in patients with physiological pacing. Many pacemaker patients experience only transient bradyarrhythmias with an adequate unpaced heart rate (UHR) and are not pacemaker-dependent. The purpose of the present analysis was to determine if pacemaker-dependent patients have an increased benefit from physiological pacing compared with non-pacemaker-dependent patients. METHODS AND RESULTS: Of 2568 patients included in the CTOPP trial, 2244 patients had a pacemaker dependency test performed at the first follow-up visit. The yearly event rate of cardiovascular death or stroke steadily increased with decreasing UHR in the ventricular pacing group, but it remained constant in the physiological pacing group. When the patients were subdivided to UHR 60 bpm, there was an interaction between pacing mode treatment and UHR subgroup. The Kaplan-Meier plot confirmed a physiological pacing advantage only in the UHR </=60 bpm subgroup. This differential effect was also present for the outcomes of cardiovascular death and total mortality. CONCLUSIONS: This study demonstrated that UHR at first follow-up has an important influence on how pacing mode selection affects cardiovascular death and total mortality. Pacemaker-dependent patients with low UHR will probably be paced frequently and will likely benefit from physiological pacing. In contrast, non-pacemaker-dependent patients will likely be paced infrequently and may not benefit from physiological pacing.
Tang et al. (Tue,) conducted a rct in Bradyarrhythmias requiring pacemaker (n=2,244). Physiological pacing vs. Ventricular pacing was evaluated on Cardiovascular death or stroke. Physiological pacing reduced cardiovascular death and total mortality compared with ventricular pacing only in pacemaker-dependent patients with an unpaced heart rate ≤60 bpm.