Xu Dongjie, Yang Bin, Shan Qijun, Zou Jiangang, Chen Minglong, Chen Chun, Hou Xiaofeng, Zhang Fengxiang, Li Wen-Qi, Cao Kejiang, Tse Hung-Fat
Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China.
J Interv Card Electrophysiol. 2009 Sep;25(3):171-4. doi: 10.1007/s10840-008-9356-5. Epub 2009 Mar 5.
A remote magnetic navigation system (MNS) has been developed for mapping and catheter ablation of cardiac arrhythmias. The present study evaluates the safety and feasibility of this system to perform radiofrequency (RF) ablation in patients with supraventricular tachycardias (SVT).
A total of 32 patients (22 female; mean age 44 +/- 16 years) with documented SVT underwent mapping and ablation using Helios II (a 4-mm-tip magnetic catheter), under the guidance of the MNS (Niobe II, Stereotaxis, Inc.).
Catheter ablation procedure with MNS was successful in 30/32 (94%) patients including all patients (27/27, 100%) with atrioventricular nodal reentrant tachycardia (AVNRT) and three of five patients (60%) with atrioventricular reentrant tachycardia (AVRT) without any complication. The procedural successful rate in patients with AVNRT was significantly higher than those in patients with AVRT (P < 0.001). Overall, the medium number of RF application using the MNS was 2 (mean 2.7 +/- 1.6, range 1 to 7), and the medium numbers of RF for AVNRT and AVRT were 2 and 3, respectively. There was no significant difference in the mean procedural time between patients with AVNRT and AVRT (126.3 +/- 38.6 vs. 138.0 +/- 40.3 min, P = 0.54). However, the mean fluoroscopy time was significantly shorter in patients with AVNRT than those with AVRT (5.7 +/- 3.0 vs. 16.5 +/- 2.5 min, P < 0.001). Among those patients with AVNRT, the mean procedural time (139.3 +/- 45.0 vs. 112.3 +/- 24.9 min, P = 0.07) and fluoroscopic time (3.2 +/- 1.0 vs. 8.0 +/- 2.2 min, P < 0.001) were shorter for the later 13 patients than the first 14 patients, suggesting a learning curve in using the MNS for RF ablation.
The Niobe MNS is a new technique that can allow safe and effective remote-controlled navigation and minimize the need for fluoroscopic guidance for ablation catheter of AVNRT. However, further improvement is required to achieve a higher successful rate for treatment of AVRT.
已研发出一种用于心脏心律失常标测和导管消融的远程磁导航系统（MNS）。本研究评估该系统在室上性心动过速（SVT）患者中进行射频（RF）消融的安全性和可行性。
共有32例记录有SVT的患者（22例女性；平均年龄44±16岁）在MNS（Niobe II，Stereotaxis公司）的引导下，使用Helios II（一种4毫米尖端的磁导管）进行标测和消融。
32例患者中有30例（94%）使用MNS进行导管消融成功，包括所有房室结折返性心动过速（AVNRT）患者（27/27，100%）和5例房室折返性心动过速（AVRT）患者中的3例（60%），且无任何并发症。AVNRT患者的手术成功率显著高于AVRT患者（P<0.001）。总体而言，使用MNS进行RF应用的平均次数为2次（平均2.7±1.6，范围1至7次），AVNRT和AVRT的RF平均次数分别为2次和3次。AVNRT患者和AVRT患者的平均手术时间无显著差异（126.3±38.6对138.0±40.3分钟，P = 0.54）。然而，AVNRT患者的平均透视时间显著短于AVRT患者（5.7±3.0对16.5±2.5分钟，P<0.001）。在那些AVNRT患者中，后13例患者的平均手术时间（139.3±45.0对112.3±24.9分钟，P = 0.07）和透视时间（3.2±1.0对8.0±2.2分钟，P<0.001）短于前14例患者，提示在使用MNS进行RF消融方面存在学习曲线。
Niobe MNS是一种新技术，可实现安全有效的远程控制导航，并最大限度减少AVNRT消融导管的透视引导需求。然而，需要进一步改进以提高AVRT的治疗成功率。
