Stöckigt Florian, Pöhlmann Sonja, Nickenig Georg, Schwab Jörg Otto, Schrickel Jan Wilko
Department of Medicine-Cardiology, University Hospital Bonn, Sigmund Freud Str. 25, 53127Bonn, Germany
Department of Medicine-Cardiology, University Hospital Bonn, Sigmund Freud Str. 25, 53127Bonn, Germany.
Europace. 2014 Jul;16(7):1092-8. doi: 10.1093/europace/eut357. Epub 2014 Mar 26.
Heart rate turbulence (HRT) is a prognostic parameter for risk stratification in patients suffering from coronary artery disease. The aims of this study were to demonstrate the feasibility of quantifying HRT in mice, both in long-term electrocardiograms (ECGs) as well as after extrastimulus pacing, and to analyse its characteristics.
We performed long-term ECG recordings using implanted telemetric chips and electrophysiological (EP) investigations, using transvenously inserted EP catheters, in healthy mice. Heart rate turbulence was calculated using the established turbulence onset (TO) and slope (TS) algorithm. After spontaneous ventricular premature complexes (VPCs), we found a negative TO (-2.2 ± 7.5%) and positive TS (15.5 ± 18.3 ms/RR interval). Electrophysiological investigations revealed positive values for TO (0.6 ± 1.1%) and TS (6.5 ± 2.9 ms/RR interval) after extrastimulus pacing maneuvers. The shortening of the extrastimuli coupling intervals delivered during EP investigations significantly influenced TO (r = 0.57; P = 0.01): shorter coupling intervals provoked more positive TO values.
Mice display both spontaneous and induced HRT. In terms of TO, VPCs generated by extrastimulus pacing are significantly dependent on the coupling interval. Determining HRT in mice is feasible and provides insight into basic mechanisms of blood pressure regulation, which is realized by the baroreflex.
心率震荡（HRT）是冠心病患者危险分层的一个预后参数。本研究的目的是证明在小鼠中量化HRT的可行性，包括在长期心电图（ECG）以及额外刺激起搏后，并分析其特征。
我们使用植入式遥测芯片对健康小鼠进行长期心电图记录，并使用经静脉插入的电生理（EP）导管进行电生理研究。使用既定的震荡起始（TO）和斜率（TS）算法计算心率震荡。在自发性室性早搏（VPC）后，我们发现TO为负值（-2.2±7.5%），TS为正值（15.5±18.3 ms/RR间期）。电生理研究显示，在额外刺激起搏操作后，TO为正值（0.6±1.1%），TS为正值（6.5±2.9 ms/RR间期）。在EP研究期间给予的额外刺激耦合间期的缩短显著影响TO（r = 0.57；P = 0.01）：较短的耦合间期引起更正值的TO值。
小鼠表现出自发性和诱发性HRT。就TO而言，由额外刺激起搏产生的VPC显著依赖于耦合间期。在小鼠中测定HRT是可行的，并能深入了解通过压力反射实现的血压调节的基本机制。
