Department of Medicine, Division of Cardiology, Columbia University Medical Center, New York, New York, USA.
Heart Rhythm. 2010 Sep;7(9):1207-15. doi: 10.1016/j.hrthm.2010.06.018. Epub 2010 Jun 15.
Complex fractionated atrial electrograms (CFAEs) may represent a phenomenon associated with sources of atrial fibrillation (AF) and are being used increasingly as targets of catheter ablation. However, current methods have limited efficacy for characterizing CFAEs important to substrate arrhythmogenicity and do not measure electrogram morphology.
The purpose of this study was to develop a methodology for quantifying the degree of morphologic heterogeneity in CFAE deflections, and to determine whether there are differences in this measurement between paroxysmal and persistent AF patients.
Two successive bipolar CFAEs of length 8.4 seconds each were acquired during AF from two sites each at the ostia of the four pulmonary veins (PVs) and from the anterior and posterior left atrial free wall in patients with paroxysmal AF (N = 10) and long-standing persistent AF (N = 10). Extrinsic and intrinsic features of electrogram shape were used to characterize fractionation in CFAE sequences. The extrinsic parameters were the amplitude, upslope, downslope, and width of each deflection. The intrinsic parameter was the voltage profile as characterized by the sum of absolute values. These measurements were compared to the mean interval between CFAE deflections, a standard fractionation indicator.
The variability of intrinsic/extrinsic morphologic parameters was higher in paroxysmal than persistent AF at the left superior PV (P < or =.003), the posterior left atrial free wall, anterior left atrial free wall, left inferior PV, and right superior PV (P <.05 for most parameters), and the right inferior PV (not significant). Mean CFAE deflection intervals were longer at all locations in paroxysmal AF but were significant only at the left superior PV and posterior left atrial free wall (P <.05). Quantitative morphologic parameters were not well correlated with dominant frequency (r(2) <0.32); thus, our new measures are robust to changes in activation rate.
A novel method for quantifying CFAEs, independent of activation rate, has been developed. The method demonstrates greater significance in the difference between CFAE morphology in paroxysmal and long-standing AF compared with mean interval between CFAE deflections. The differences identified suggest that CFAE morphology may evolve as AF persists.
复杂碎裂心房电图（CFAE）可能代表与心房颤动（AF）相关的源的现象，并且越来越多地被用作导管消融的靶点。然而，目前的方法对表征与基质致心律失常性相关的重要 CFAE 的有效性有限，并且不测量电描记图形态。
本研究旨在开发一种量化 CFAE 偏转形态异质性程度的方法，并确定该测量方法在阵发性和持续性 AF 患者之间是否存在差异。
从阵发性 AF 患者（N = 10）和持续性 AF 患者（N = 10）的四个肺静脉（PV）口的每侧两个部位以及左心房前壁和后壁获取长度为 8.4 秒的两个连续双极 CFAE。使用电描记图形状的外在和内在特征来描述 CFAE 序列中的碎裂。外在参数是每个偏转的幅度、斜率上升、斜率下降和宽度。内在参数是特征为绝对值之和的电压分布。将这些测量值与 CFAE 偏转之间的平均间隔（标准碎裂指标）进行比较。
与持续性 AF 相比，阵发性 AF 时左上方 PV（P < 0.003）、左心房后壁、左心房前壁、左下方 PV 和右上方 PV（大多数参数 P <.05）以及右下方 PV（不显著）的内在/外在形态参数的变异性更高。在阵发性 AF 中，所有部位的 CFAE 偏转间隔较长，但仅在左上方 PV 和左心房后壁有统计学意义（P <.05）。定量形态参数与主导频率相关性较差（r2 < 0.32）；因此，我们的新方法对激活率的变化具有鲁棒性。
已经开发出一种量化 CFAE 的新方法，该方法独立于激活率。与 CFAE 偏转之间的平均间隔相比，该方法在阵发性和持续性 AF 之间的 CFAE 形态差异方面具有更大的意义。所确定的差异表明，随着 AF 的持续，CFAE 形态可能会发生演变。
