Ryser Adrian, Reichlin Tobias, Burger Jürgen, Niederhauser Thomas, Haeberlin Andreas
Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse 20, 3010 Bern, BE Switzerland.
School for Cellular and Biomedical Sciences, University of Bern, Mittelstrasse 43, 3012 Bern, BE Switzerland.
Biomed Eng Lett. 2024 Aug 19;14(6):1397-1407. doi: 10.1007/s13534-024-00413-z. eCollection 2024 Nov.
Dual-chamber leadless pacemakers (LLPMs) consist of two implants, one in the right atrium and one in the right ventricle. Inter-device communication, required for atrioventricular (AV) synchrony, however, reduces the projected longevity of commercial dual-chamber LLPMs by 35-45%. This work analyzes the power-saving potential and the resulting impact on AV-synchrony for a novel LLPM synchronization protocol. Relevant parameters of the proposed window scheduling algorithm were optimized with system-level simulations investigating the resulting trade-off between transceiver current consumption and AV-synchrony. The parameter set included the algorithm's setpoint for the target number of windows per cardiac cycle and the number of averaging cycles used in the window update calculation. The sensing inputs for the LLPM model were derived from human electrocardiogram recordings in the MIT-BIH Arrhythmia Database. Transceiver current consumption was estimated by combining the simulation results on the required communication resources with electrical measurements of a receiver microchip developed for LLPM synchronization in previous work. The performance ratio given by AV-synchrony divided by current consumption was maximized for a target of one window per cardiac cycle and three averaging cycles. Median transceiver current of both LLPMs combined was 166 nA (interquartile range: 152-183 nA) and median AV-synchrony was 92.5%. This corresponded to median reduction of 18.3% and 3.2% in current consumption and AV-synchrony, respectively, compared to a non-rate-responsive implementation of the same protocol, which prioritized maximum AV-synchrony. In conclusion, adopting a rate-responsive communication protocol may significantly increase device longevity of dual-chamber LLPMs without compromising AV-synchrony, potentially reducing the frequency of device replacements.
双腔无导线起搏器（LLPMs）由两个植入部件组成，一个植入右心房，一个植入右心室。然而，实现房室（AV）同步所需的设备间通信会使商用双腔LLPMs的预计使用寿命缩短35%至45%。这项工作分析了一种新型LLPM同步协议的节能潜力及其对AV同步的影响。通过系统级模拟优化了所提出的窗口调度算法的相关参数，研究了收发器电流消耗与AV同步之间的权衡。参数集包括算法每个心动周期目标窗口数的设定点以及窗口更新计算中使用的平均周期数。LLPM模型的传感输入来自麻省理工学院 - 贝斯以色列女执事医疗中心心律失常数据库中的人类心电图记录。通过将所需通信资源的模拟结果与先前工作中为LLPM同步开发的接收器微芯片的电气测量结果相结合，估计了收发器电流消耗。对于每个心动周期一个窗口和三个平均周期的目标，AV同步除以电流消耗得出的性能比最大化。两个LLPM组合的收发器电流中位数为166 nA（四分位间距：152 - 183 nA），AV同步中位数为92.5%。与同一协议的非频率响应实现相比，这分别对应于电流消耗和AV同步中位数分别降低了18.3%和3.2%，后者优先考虑最大AV同步。总之，采用频率响应通信协议可能会显著提高双腔LLPMs的设备使用寿命，而不会损害AV同步，有可能减少设备更换频率。
