Rate adaptive pacing in people with chronic heart failure increases peak heart rate but not peak exercise capacity: a systematic review

Abstract

Rate adaptive cardiac pacing (RAP) allows increased heart rate (HR) in response to metabolic demand in people with implantable electronic cardiac devices (IECD). The aim of this work was to conduct a systematic review to determine if RAP increases peak exercise capacity (peak VO2) in line with peak HR in people with chronic heart failure. We conducted a systematic literature search from 1980, when IECD and RAP were first introduced, until 31 July 2021. Databases searched include PubMed, Medline, EMBASE, EBSCO, and the Clinical Trials Register. A comprehensive search of the literature produced a total of 246 possible studies; of these, 14 studies were included. Studies and subsequent analyses were segregated according to comparison, specifically standard RAP (RAPON) vs fixed rate pacing (RAPOFF), and tailored RAP (TLD RAPON) vs standard RAP (RAPON). Pooled analyses were conducted for peak VO2 and peak HR for RAPON vs RAPOFF. Peak HR significantly increased by 15 bpm with RAPON compared to RAPOFF (95%CI, 7.98–21.97, P < 0.0001). There was no significant difference between pacing mode for peak VO2 0.45 ml kg−1 min−1 (95%CI, − 0.55–1.47, P = 0.38). This systematic review revealed RAP increased peak HR in people with CHF; however, there was no concomitant improvement in peak VO2. Rather RAP may provide benefits at submaximal intensities by controlling the rise in HR to optimise cardiac output at lower workloads. HR may be an important outcome of CHF management, reflecting myocardial efficiency.

Rate-Adaptive Pacing for Heart Failure With Preserved Ejection Fraction

“…There are other ongoing pacing trials in HFpEF (NCT04546555; NCT03338374), and a recent trial suggested benefit from a higher backup pacing rate among patients with subclinical or overt HFpEF who already had pacemaker implantation for other indications . However, a recent meta-analysis of pacing for heart failure supports the results of the presently reported trial, furthering the case for abandoning rate-adaptive pacing for most patients with HFpEF, despite their chronotropic incompetence.…”

Atrial paced rhythm and heart rate‐dependent worsening of left atrial and ventricular function

“…In patients with a pacemaker or ICD, the devices are generally programmed with the function of HR responsiveness (RR), developed to restore a physiological HR response to increased metabolic demand and face the chronotropic incompetence typical of patients with HF. 17,18 However, in patients with HF with reduced LVEF, it is significant to decrease the basal HR using a pharmacological approach and the programming of the devices because the decrease in the HR at rest reduces the oxygen demand and improves the degree of global metabolic efficiency. 19 Moreover, the association between increased HR and exercise capacity is weak in patients with HF with reduced ejection fraction; this is even more evident in patients with severe LV systolic dysfunction.…”

“…Our results, which showed an HR increase, could lead to atrioventricular uncoupling, which lead to some considerations on HR management among patients with LV dysfunction. In patients with a pacemaker or ICD, the devices are generally programmed with the function of HR responsiveness (RR), developed to restore a physiological HR response to increased metabolic demand and face the chronotropic incompetence typical of patients with HF 17,18 . However, in patients with HF with reduced LVEF, it is significant to decrease the basal HR using a pharmacological approach and the programming of the devices because the decrease in the HR at rest reduces the oxygen demand and improves the degree of global metabolic efficiency 19 .…”

“…Interestingly, the worsening of both LA and LV functions assessed by strain was more evident at the rate of 90 bpm. Therefore, as already highlighted in the literature, 18 considering the significance of low basal HR and that the increase in the peak frequency has not demonstrated a real benefit, the application of the RR function could be limited to frequencies that are not very high (a greater deterioration in the deformation parameters is noted at 90 bpm) and could be more suitable for modulating the increase in frequency at submaximal loads rather than increasing the peak HR.…”

Remodeling in the AV block dog is essential for tolerating moderate treadmill activity

“…Complex device technologies and algorithms developed over the last four decades focus on rate-adaptive pacing based on physiological input, including physical activity [3] , transthoracic impedance [4] , respiration [5] , [6] , and even a combination of various physiological parameters [7] . However, optimization of sensor sensitivity is challenging, and studies lack significant improvement outcome of the sensors on top of pacing at a fixed rate to treat bradycardia [8] , [9] . Testing of new developed complex devices and algorithms for treatment of cardiorespiratory diseases by rate-adaptive pacing will benefit from a standardized preclinical model in which evaluation of diverse physiological parameters in conditions of rest and activity are incorporated.…”