Atrial High Rate Episodes Detected by Pacemaker Diagnostics Predict Death and Stroke

Abstract

Background-Some current pacing systems can automatically detect and record atrial tachyarrhythmias that may be asymptomatic. We prospectively studied a 312-patient (pt) subgroup of MOST (MOde Selection Trial), a 2010-patient, 6-year randomized trial of DDDR versus VVIR pacing in sinus node dysfunction (SND). The purpose of the study was to correlate atrial high rate events (AHREs) detected by pacemaker diagnostics with clinical outcomes. Methods and Results-Pacemakers were programmed to log an AHRE when the atrial rate was Ͼ220 bpm for 10 consecutive beats. Analysis was confined to patients with at least 1 AHRE duration exceeding 5 minutes. The 312 patients were median age 74 years, 55% female, and 60% had a history of SVT. 160 of 312 (51.3%) patients enrolled had at least 1 AHRE Ͼ5 minutes duration over median follow-up of 27 months. Cox proportional hazards analysis assessed the relationship of AHREs with clinical events, adjusting for prognostic variables and baseline covariates. The presence of any AHRE was an independent predictor of the following: total mortality (hazard ratio AHRE versus no AHRE and 95% confidence intervalsϭ2.

Remote patient management using implantable devices

“…Atrial high-rate episodes are the most common arrhythmia recorded by wireless devices [8,9]. It has previously been shown that atrial high-rate episodes lasting ≥5 min double the risk of stroke or death in patients with sinus node dysfunction who undergo dual-chamber pacemaker implantation [10]. However, there are certain undetermined considerations.…”

Value of implantable cardioverter-defibrillators in managing atrial fibrillation

“…23 In contrast, another study looking at the duration of atrial high rate events, found that only episodes lasting longer than one day increased risk. 27 The investigators also noted that 12% of the cohort received an ICD shock during the first 3 months after implantation.…”

“…22 Furthermore, detection of atrial high-rate events in devices is a predictor of poor outcome. 23 Based on these observations, it is likely that the current estimates of AF prevalence in the general population may eventually be revised upward. Rhythm Classification algorithm) in patients with and without a history of AF.…”

Detection and management of atrial fibrillation after cryptogenic stroke or embolic stroke of undetermined source

“…The threshold for a significant increase of TE risk varied from 5 minutes to 24 hours. [17][18][19][44][45][46][47] It seems reasonable to speculate that the implications of AF burden may be different in patients with different baseline risks, in particular in patients with or without prior stroke. An interesting observation supporting the hypothesis of a multivariable model and the absence of a fixed threshold predictive of increased risk is suggested from a proof-of-concept study in which the risk of stroke or TE events was found to be not only a function of the time spent in AF, but also of the baseline characteristics of the patients.…”