Chang Shih-Lin, Tai Ching-Tai, Lin Yenn-Jiang, Wongcharoen Wanwarang, Lo Li-Wei, Lee Kun-Tai, Chang Sheng-Hsiung, Tuan Ta-Chuan, Chen Yi-Jen, Hsieh Ming-Hsiung, Tsao Hsuan-Ming, Wu Mei-Han, Sheu Ming-Huei, Chang Cheng-Yen, Chen Shih-Ann
Division of Cardiology and Cardiovascular Research Center, National Yang-Ming University, School of Medicine, Taipei, Taiwan.
J Am Coll Cardiol. 2007 Sep 4;50(10):964-73. doi: 10.1016/j.jacc.2007.05.026. Epub 2007 Aug 20.
We sought to investigate the imaging of the left atrial (LA) muscular bundle and the relationship between the bundle and inducibility of tachyarrhythmia after pulmonary vein isolation (PVI).
Noninducibility is used as a clinical end point of atrial substrate ablation after PVI. However, little is known about the role of the LA muscular bundles in tachyarrhythmia after PVI.
Forty-three consecutive patients with paroxysmal atrial fibrillation who underwent catheter ablation were included. Bi-atrial isochronal mapping was performed with the NavX system (St. Jude Medical Inc., St. Paul, Minnesota) during sinus rhythm. After 4 PVI, inducible organized LA flutter with or without transforming to atrial fibrillation (AF) (LA flutter/AF) was ablated with additional lines at the roof and/or mitral isthmus.
The existence of bilateral muscular bundles was an independent predictor of LA flutter/AF after PVI (p = 0.02). Patients with LA flutter/AF after PVI had a greater index of the double potentials (5.4 +/- 3.4% vs. 2.8 +/- 1.8%, p = 0.006) and interpotential interval (33 +/- 5 ms vs. 29 +/- 4 ms, p = 0.02) than without LA flutter/AF. The muscular bundles were identified in 28% patients using 16-slice multidetector computed tomography, which were identical to the isochrone map. Patients with noninducible LA flutter/AF after PVI plus the additional linear ablation had a lower recurrence rate as compared with the patients without it (19% vs. 75%, p = 0.02).
Left atrial muscular bundles may provide a conduction block line and barrier, which is important for the formation of LA flutter/AF after PVI. The noninducibility of LA flutter/AF achieved after additional linear ablation may contribute to a better outcome in RF ablation of paroxysmal atrial fibrillation.
我们试图研究左心房（LA）肌束的成像以及肺静脉隔离（PVI）后该肌束与快速性心律失常诱发之间的关系。
不能诱发快速性心律失常被用作PVI后心房基质消融的临床终点。然而，关于LA肌束在PVI后快速性心律失常中的作用知之甚少。
纳入43例接受导管消融的阵发性心房颤动连续患者。在窦性心律期间使用NavX系统（圣犹达医疗公司，明尼苏达州圣保罗）进行双心房等时标测。4次PVI后，对诱发的有组织的LA扑动伴或不伴转变为心房颤动（AF）（LA扑动/AF），在房顶和/或二尖瓣峡部用额外的线性消融线进行消融。
双侧肌束的存在是PVI后LA扑动/AF的独立预测因素（p = 0.02）。PVI后发生LA扑动/AF的患者双电位指数（5.4±3.4%对2.8±1.8%，p = 0.006）和电位间期（33±5毫秒对29±4毫秒，p = 0.02）高于未发生LA扑动/AF的患者。使用16层多排螺旋计算机断层扫描在28%的患者中识别出肌束，其与等时图一致。PVI后加用额外线性消融不能诱发LA扑动/AF的患者与未加用者相比复发率更低（19%对75%，p = 0.02）。
左心房肌束可能提供传导阻滞线和屏障，这对PVI后LA扑动/AF的形成很重要。额外线性消融后实现的LA扑动/AF不能诱发可能有助于阵发性心房颤动射频消融取得更好的结果。
