Department of Cardiology, Kepler University Hospital, Linz, Austria; Department of Cardiology, Paracelsus Medical University Salzburg, Salzburg, Austria.
Department of Electrophysiology, Institut Jantung Negara, Kuala Lumpur, Malaysia.
JACC Clin Electrophysiol. 2020 Jan;6(1):94-106. doi: 10.1016/j.jacep.2019.10.017. Epub 2019 Nov 11.
This study reports on the performance of a leadless ventricular pacemaker with automated, enhanced accelerometer-based algorithms that provide atrioventricular (AV) synchronous pacing.
Despite many advantages, leadless pacemakers are currently only capable of single-chamber ventricular pacing.
The prospective MARVEL 2 (Micra Atrial tRacking using a Ventricular accELerometer 2) study assessed the performance of an automated, enhanced accelerometer-based algorithm downloaded to the Micra leadless pacemaker for up to 5 h in patients with AV block. The primary efficacy objective was to demonstrate the superiority of the algorithm to provide AV synchronous (VDD) pacing versus VVI-50 pacing in patients with sinus rhythm and complete AV block. The primary safety objective was to demonstrate that the algorithm did not result in pauses or heart rates of >100 beats/min.
Overall, 75 patients from 12 centers were enrolled; an accelerometer-based algorithm was downloaded to their leadless pacemakers. Among the 40 patients with sinus rhythm and complete AV block included in the primary efficacy objective analysis, the proportion of patients with ≥70% AV synchrony at rest was significantly greater with VDD pacing than with VVI pacing (95% vs. 0%; p < 0.001). The mean percentage of AV synchrony increased from 26.8% (median: 26.9%) during VVI pacing to 89.2% (median: 94.3%) during VDD pacing. There were no pauses or episodes of oversensing-induced tachycardia reported during VDD pacing in all 75 patients.
Accelerometer-based atrial sensing with an automated, enhanced algorithm significantly improved AV synchrony in patients with sinus rhythm and AV block who were implanted with a leadless ventricular pacemaker. (Micra Atrial Tracking Using a Ventricular Accelerometer 2 [MARVEL 2]; NCT03752151).
本研究报告了一种无导线心室起搏器的性能，该起搏器具有自动、增强的基于加速度计的算法，可提供房室（AV）同步起搏。
尽管无导线起搏器有许多优点，但目前仅能进行单腔心室起搏。
前瞻性 MARVEL 2（使用心室加速度计进行 Micra 心房跟踪 2）研究评估了一种自动、增强的基于加速度计的算法在房室传导阻滞患者中下载到 Micra 无导线起搏器后长达 5 小时的性能。主要疗效指标是证明该算法在窦性心律和完全房室传导阻滞患者中提供房室同步（VDD）起搏优于 VVI-50 起搏。主要安全性指标是证明该算法不会导致起搏暂停或心率>100 次/分钟。
总体而言，来自 12 个中心的 75 名患者入组；他们的无导线起搏器下载了基于加速度计的算法。在主要疗效指标分析中，40 名窦性心律和完全房室传导阻滞的患者中，VDD 起搏时≥70% AV 同步的患者比例明显高于 VVI 起搏（95% vs. 0%；p<0.001）。在 VVI 起搏时，AV 同步的平均百分比从 26.8%（中位数：26.9%）增加到 VDD 起搏时的 89.2%（中位数：94.3%）。在所有 75 名患者中，VDD 起搏时均未报告起搏暂停或感知过度引起的心动过速事件。
在植入无导线心室起搏器的窦性心律和房室传导阻滞患者中，基于加速度计的心房感知和自动、增强算法显著改善了 AV 同步性。（Micra 心房跟踪使用心室加速度计 2 [MARVEL 2]；NCT03752151）。
