Institute of Biomedical Engineering, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany.
IEEE Trans Biomed Eng. 2011 Sep;58(9):2648-55. doi: 10.1109/TBME.2011.2160453. Epub 2011 Jun 23.
Conduction velocity (CV) and CV restitution are important substrate parameters for understanding atrial arrhythmias. The aim of this work is to (i) present a simple but feasible method to measure CV restitution in-vivo using standard circular catheters, and (ii) validate its feasibility with data measured during incremental pacing. From five patients undergoing catheter ablation, we analyzed eight datasets from sinus rhythm and incremental pacing sequences. Every wavefront was measured with a circular catheter and the electrograms were analyzed with a cosine-fit method that calculated the local CV. For each pacing cycle length, the mean local CV was determined. Furthermore, changes in global CV were estimated from the time delay between pacing stimulus and wavefront arrival. Comparing local and global CV between pacing at 500 and 300 ms, we found significant changes in seven of eight pacing sequences. On average, local CV decreased by 20 ± 15% and global CV by 17 ± 13%. The method allows for in-vivo measurements of absolute CV and CV restitution during standard clinical procedures. Such data may provide valuable insights into mechanisms of atrial arrhythmias. This is important both for improving cardiac models and also for clinical applications, such as characterizing arrhythmogenic substrates during sinus rhythm.
传导速度 (CV) 和 CV 恢复是理解心房心律失常的重要底物参数。本工作的目的是：(i) 提出一种使用标准圆形导管在体内测量 CV 恢复的简单但可行的方法；(ii) 通过递增起搏测量的数据验证其可行性。从接受导管消融的五名患者中，我们分析了窦性节律和递增起搏序列的八个数据集。使用圆形导管测量每个波阵面，并使用余弦拟合方法分析电描记图，该方法计算局部 CV。对于每个起搏周期长度，确定平均局部 CV。此外，从起搏刺激和波阵面到达之间的时间延迟估计全局 CV 的变化。比较起搏在 500 和 300 ms 时的局部和全局 CV，我们在八个起搏序列中的七个中发现了显著变化。平均而言，局部 CV 降低了 20 ± 15%，全局 CV 降低了 17 ± 13%。该方法允许在标准临床程序中进行体内测量绝对 CV 和 CV 恢复。这些数据可能为心房心律失常的机制提供有价值的见解。这对于改进心脏模型以及在窦性节律期间表征致心律失常底物等临床应用都很重要。
