Left Univentricular Pacing by Rate-Adaptive Atrioventricular Delay in Treatment of Chronic Heart Failure

Abstract

BackgroundCardiac resynchronization therapy (CRT) is efficacious in the treatment of chronic heart failure (CHF); however, because it is non-physiological, some patients are unresponsive. The present study used rate-adaptive atrioventricular delay (RAAVD) to track the physiological atrioventricular delay and investigated the effects of left univentricular pacing on CRT.Material/MethodsPatients with CHF fulfilling the indication of CRT Class I were categorized into a left univentricular pacing by RAAVD group and a standard biventricular pacing group. Preoperative and postoperative electrocardiography QRS duration, echocardiographic indicators, quality of life, cardiac function, and annual treatment cost were estimated. The standard deviation (RS/R-SD5) of the S/R ratio in lead V1 at 5 heart rate segments in the left univentricular pacing by RAAVD was calculated, and the accuracy of RAAVD in tracking the physiological AV delay was evaluated.ResultsThe comparison between the left univentricular pacing by RAAVD group and the standard biventricular pacing group after operation showed a significantly reduced QRS duration (137±11 vs. 144±11 ms, P<0.05), increased AVVTI (21.84±2.25 vs. 20.45±2.12 cm, P<0.05), reduced IVMD (64.27±12.29 vs. 71.39±13.64 ms, P<0.05), decreased MRA (3.09±1.12 vs. 3.73±1.19 cm2, P<0.05), and reduced average annual treatment cost (1.30±0.1 vs. 2.20±0.2 million Yuan, P<0.05). The RS/R-SD5 in the left univentricular pacing by RAAVD group was negatively correlated with improvements in cardiac function (r=−0.394, P=0.031).ConclusionsLeft univentricular pacing by RAAVD has treatment effects similar to those of standard biventricular pacing, and is an economically and physiologically effective method for biventricular systolic resynchronization in the treatment of CHF.

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

“…Ten studies compared standard RAP (RAPON) with fixed rate pacing (RAPOFF) (Table 1) [5,12,22,29,[31][32][33][34][35][36]. Two studies were randomised control trials [12,29], while the remaining eight were cross over trials. In particular, the study conducted by Kass and colleagues [31] was suspended due to poor recruitment.…”

“…RAP sensors included accelerometers [21,30,32,33,36] and blended minute ventilation and accelerometers [31]. Six studies did not specify the sensor used [5,12,22,29,34,35].…”

“…Four studies assessed exercise capacity using 6MWT [12,29,32,35]. Differing study designs did not permit pooled analysis.…”

“…Alternatively, the 6MWT may be more relevant to assess capacity to perform activities of daily living, holding greater relevance when assessing RAP [67,71]. In this review, all studies comparing RAPON vs RAPOFF demonstrated a trend towards an improvement in 6MWT [12,29,32,35] and two studies observed a significant increase [32,35]. This may reflect the rate control of RAP, which mimics a more physiological rise in HR in the early stages of exercise, compared to a standard linear increase in RAPOFF.…”

Fusion Pacing with Biventricular, Left Ventricular-only and Multipoint Pacing in Cardiac Resynchronisation Therapy: Latest Evidence and Strategies for Use

“…It has also been explored for HF patients with CRT indications in developing countries with restricted resources where dual chamber pacemakers have been implanted with LV leads for patients with HF, LBBB and intact AV conduction. [ 86 ] This non-randomised study included 30 patients receiving LV univentricular pacemakers and showed non-inferiority by clinical and echo criteria but significant cost savings at 6 months versus standard BiV pacing with fixed AV intervals. AV delay optimisation was performed using echo and 10 ms decrements from the resting PR interval prior to initiating rate adaptive AV delay algorithms.…”