Meunier Jason M, Ramalingam Sanjiv, Lin Shien-Fong, Patwardhan Abhijit R
2 Wenner-Gren Research Laboratory, The Center for Biomedical Engineering, The University of Kentucky, Lexington, KY 40506-0070, USA.
J Interv Card Electrophysiol. 2007 Apr;18(3):207-15. doi: 10.1007/s10840-007-9094-0. Epub 2007 May 23.
Results of previous studies suggest that pacing strength stimuli can capture activation during ventricular arrhythmia locally near pacing sites. The existence of spatio-temporal distribution of excitable gap during arrhythmia suggests that multiple and timed stimuli delivered over a region may permit capture over larger areas.
Our objective in this study was to evaluate the efficacy of using spatially distributed pacing (DP) to capture activation during ventricular arrhythmia.
Data were obtained from rabbit hearts which were placed against a lattice of parallel wires through which biphasic pacing stimuli were delivered. Electrical activity was recorded optically. Pacing stimuli were delivered in sequence through the parallel wires starting with the wire closest to the apex and ending with one closest to the base. Inter-stimulus delay was based on conduction velocity. Time-frequency analysis of optical signals was used to determine variability in activation. A decrease in standard deviation of dominant frequencies of activation from a grid of locations that spanned the captured area and a concurrence with paced frequency were used as an index of capture.
Results from five animals showed that the average standard deviation decreased from 0.81 Hz during arrhythmia to 0.66 Hz during DP at pacing cycle length of 125 ms (p = 0.03) reflecting decreased spatio-temporal variability in activation during DP. Results of time-frequency analysis during these pacing trials showed agreement between activation and paced frequencies.
These results show that spatially distributed and timed stimulation can be used to modify and capture activation during ventricular arrhythmia.
先前研究结果表明，起搏强度刺激可在起搏部位附近局部捕获室性心律失常期间的激动。心律失常期间可兴奋间隙的时空分布的存在表明，在一个区域内递送多个定时刺激可能允许在更大区域捕获激动。
本研究的目的是评估使用空间分布起搏（DP）捕获室性心律失常期间激动的疗效。
从兔心脏获取数据，将兔心脏置于平行导线网格上，通过该网格递送双相起搏刺激。以光学方式记录电活动。起搏刺激通过平行导线依次递送，从最靠近心尖的导线开始，到最靠近心底的导线结束。刺激间期基于传导速度。对光信号进行时频分析以确定激动的变异性。将跨越捕获区域的位置网格的激动主导频率标准差的降低以及与起搏频率的一致性用作捕获指标。
五只动物的结果表明，在125 ms的起搏周期长度下，平均标准差从心律失常期间的0.81 Hz降至DP期间的0.66 Hz（p = 0.03），反映出DP期间激动的时空变异性降低。这些起搏试验期间的时频分析结果显示激动与起搏频率一致。
这些结果表明，空间分布和定时刺激可用于在室性心律失常期间改变和捕获激动。
