Department of Cardiology, Royal Melbourne Hospital, Melbourne, Australia; Department of Medicine, University of Melbourne, Melbourne, Australia.
Department of Cardiology, Royal Melbourne Hospital, Melbourne, Australia.
JACC Clin Electrophysiol. 2019 Nov;5(11):1265-1277. doi: 10.1016/j.jacep.2019.06.002. Epub 2019 Jul 31.
This study sought to determine the impact of rate and direction on left atrial (LA) substrate.
The extent to which substrate mapped in sinus rhythm varies according to cycle length and direction of wave front propagation is unknown.
A total of 73 consecutive patients with atrial fibrillation (AF) underwent electroanatomic LA mapping before pulmonary vein isolation using multipolar catheter during distal coronary sinus (CS) pacing at 600 ms and 300 ms. Additional maps were created during left superior pulmonary vein pacing at 300 ms. Bipolar voltage, conduction velocity (CV), and complex signals were determined.
Mean age was 61 ± 9 years, 67% were men, and 53% had persistent AF. Global mean voltage was lower with CS pacing at 300 ms compared with 600 ms (1.56 ± 0.47 mV vs. 1.74 ± 0.48 mV; p < 0.001). This was seen in all LA segments. Global CV was reduced (30.4 ± 13.0 cm/s vs. 38.6 ± 14.0 cm/s; p < 0.001) with greater complex signals at 300 ms (8.9% vs. 5.3%; p < 0.005). Compared with CS pacing, left superior pulmonary vein pacing demonstrated highly regional changes with decreased voltage (1.04 ± 0.43 mV vs. 1.47 ± 0.53 mV; p = 0.01) and CV (24.4 ± 13.0 cm/s vs. 39.9 ± 16.6 cm/s; p = 0.008), and greater complex signals posteriorly. Longer AF duration in paroxysmal AF (p = 0.02) and shorter duration in persistent AF (p = 0.015) and left ventricular ejection fraction (p = 0.016) were independent predictors of voltage change.
In patients with AF, variation in cycle length and direction of wave front activation produce both generalized and regional changes in voltage, CV, and complex fractionation, resulting in significant changes in substrate maps. This study highlights the potential limitations of static low-voltage maps to identify the AF ablation target zone.
本研究旨在确定激动频率和方向对左心房（LA）基质的影响。
窦性心律下激动基质标测根据激动波前传播的周长和方向的不同而变化的程度尚不清楚。
连续 73 例心房颤动（AF）患者在行肺静脉隔离前，使用多极导管在心外膜冠状窦（CS）行 600ms 和 300ms 远端起搏，同时在左肺上静脉行 300ms 起搏。在左肺上静脉起搏时还创建了其他图。测定双极电压、传导速度（CV）和复杂信号。
平均年龄 61±9 岁，67%为男性，53%为持续性 AF。与 600ms 相比，CS 起搏 300ms 时平均电压更低（1.56±0.47mV 比 1.74±0.48mV；p<0.001）。这种情况见于所有 LA 节段。CV 降低（30.4±13.0cm/s 比 38.6±14.0cm/s；p<0.001），300ms 时复杂信号更多（8.9%比 5.3%；p<0.005）。与 CS 起搏相比，左肺上静脉起搏表现出高度区域性变化，电压降低（1.04±0.43mV 比 1.47±0.53mV；p=0.01），CV 降低（24.4±13.0cm/s 比 39.9±16.6cm/s；p=0.008），后侧壁的复杂信号增加。阵发性 AF 的 AF 持续时间较长（p=0.02）、持续性 AF 的持续时间较短（p=0.015）和左心室射血分数较低（p=0.016）是电压变化的独立预测因素。
在 AF 患者中，激动波前周长和方向的变化导致电压、CV 和复杂碎裂的广泛和区域性变化，从而导致基质图的显著变化。本研究强调了静态低电压图在识别 AF 消融靶点区域方面的潜在局限性。
